Blaise Pascal, măreţia şi nimicnicia omului (Cugetări, Scrieri alese).Prin triumful heliocentrismului, gândirea renascentistă şi cea modernă marchează răsturnarea viziunii

cosmologice geocentrice impuse de teologia medievală, căştigând acum teren ideea infinităţii lumii, veritabilă temă de reflecţie metafizică. Pascal o receptează în mod acut şi, precum reiese din faimoasele sale Cugetări, îi provoacă intense frământări lăuntrice, devenind pretextul dezbaterii unei probleme fundamentale, aceea a condiţiei umane. Omul este raportat la întregul existenţei, doar dintr-o asemenea perspectivă putându-se obţine o reprezentare clară a locului, rostului şi valorii sale în lume, implicit o judecată potrivită asupra înfăptuirilor sale, a produselor civilizaţiei şi culturii. Intenţia mărturisită este aceea de a-l scutura pe om din starea de somnolenţă indiferentă şi confortabilă în care se complace, de a-l determina să-şi asume lucid – fără orgolii false sau complexe umilitoare – poziţia şi destinul în univers. Raportat la infinitatea spaţio-temporală, el nu este decât „nimic”, relevându-i-se situaţia precară şi mizeră, limitată şi nefericită de fiinţă prea adesea rătăcită, orbită, solitară, plictisită. Ar decurge de aici o viziune pesimistă, care va fi imediat corijată prin compararea omului la „neant”, iar noul unghi de abordare îi va releva, în mod optimist, calitatea de a fi „totul”, adică o făptură demnă, grandioasă, excepţională, o încoronare a naturii. Filosoful francez va sfârşi prin a-i rezerva o poziţie mediană între infinitate şi nimicnicie, plasându-l pe undeva la jumătatea distanţei dintre cele două extreme.

Găsirea acestui punct intermediar îi va permite lui Pascal să se delimiteze atât de concepţia anticului Epictet – care văzuse numai măreţia omului, forţa raţiunii şi a caracterului, sublimul datoriei, care îi exaltase calităţile şi îi eludase imperfecţiunile –, cât şi de aceea aparţinând francezului Michel de Montaigne, care, dimpotrivă, subliniase numai defectele şi slăbiciunile naturii umane, incapacităţile intelectului şi capitulările voinţei, laşitatea sa morală, ignorându-i virtuţile şi meritele. Va impune o viziune duală, înălţând şi coborând omul, proslăvindu-i grandoarea şi demnitatea, deplorându-i carenţele şi scăderile. Expresia acestei neîncetate pendulări este panseul pascalian în care îl taxează deopotrivă ca „monstru” şi „miracol”, „judecător al tuturor lucrurilor” şi „imbecil vierme de pământ”, „depozitar al adevărului” şi „îngrămădire de incertitudine şi de eroare”, „mărire şi lepădătură a universului”.

Sunt semnalate astfel contradicţiile ireductibile ale naturii umane. Prin funciara-i complexitate, omul este prin excelenţă o specie a lui homo duplex, o fiinţă duală, un amestec haotic, deconcertant de spirit şi materie, de lumini şi umbre, de calităţi şi defecte, de înclinaţii superioare şi porniri bestiale, de raţiune şi pasionalitate, de orgoliu şi umilinţă, de virtute şi viciu, de forţă şi slăbiciune. După cum va nota într-un alt aforism, el nu este „nici înger, nici animal”, ci – se poate spune – şi una şi alta. Rătăceşte, nu ştie unde să se aşeze şi fixeze, caută fericirea, i se pare că a dobândit-o, însă o pierde, pentru a-şi reîncepe căutarea. Faţă de restul universului dispune totuşi de un avantaj considerabil – ceea ce-i conferă de altfel specificitate în raport cu alte vieţuitoare, superioritate şi demnitate – anume că, atunci când suferă, el ştie acest lucru. Ca fiinţă conştientă, îşi dă seama de toate „nenorocirile” care îi marchează diferitele momente ale vieţii. Iar această trăsătură îl înnobilează, îl înalţă la rangul de „mare senior”, de „rege deposedat”. Pe de altă parte, condiţia umană este finită, limitată, fragilă, fiind suficientă o singură „picătură de apă” pentru ca omul să fie ucis. Spre deosebire însă de restul lucrurilor şi fiinţelor din natură, el ştie că moare, posedă deci conştiinţa extincţiei sale într-un viitor incert. Este o „trestie” firavă, însă una cugetătoare, tocmai raţiunea fiind aceea care îl separă şi îl opune faţă de tot ce există în lume. Asemeni ei, se mlădiază sub bătaia vântului şi izbuteşte să nu se frângă. Supleţea gândirii, maleabilitatea ei, îl face să reziste chiar forţei brute a universului care, uneori, pare a conspira spre a-l distruge.

http://ro.wikipedia.org/wiki/Blaise_PascalBlaise PascalDe la Wikipedia, enciclopedia liberăBlaise Pascal (19 iunie 1623 - 19 august 1662) a fost un matematician, fizician şi filosof francez având contribuţii în numeroase domenii ale ştiinţei, precum construcţia unor calculatoare mecanice, consideraţii asupra teoriei probabilităţilor, studiul fluidelor prin clarificarea conceptelor de presiune şi vid. În urma unei revelaţii religioase în 1654, Pascal abandonează matematica şi ştiinţele exacte şi îşi dedică viaţa filozofiei şi teologiei.În onoarea contribuţiilor sale în ştiinţă numele Pascal a fost dat unităţii de măsură a presiunii, precum şi unui limbaj de progamare.S-a născut în Clermont la 19 iunie 1623 (acum Clermont-Ferrand), în regiunea Auvergne din Franţa. Blaise Pascal a fost al treilea copil al lui Etienne Pascal şi singurul său fiu. Mama lui Blaise a murit când acesta avea doar trei ani, micul Blaise fiind foarte afectat de această pierdere. În 1632, Etienne şi cei patru copii ai săi au părăsit Clermont pentru a se stabili la Paris, iar tatăl, un matematician cu vederi mai neortodoxe asupra educaţiei, a stabilit că Blaise nu va învăţa nimic despre matematică până la vârsta de 15 ani. Impulsionat de această interdicţie, la vârsta de 12 ani, Blaise a început să înveţe geometrie de unul singur, descoperind că „suma unghiurilor unui triunghi este egală cu 2 unghiuri drepte“. Când a aflat tatăl său, s-a îmbunat şi i-a permis lui Blaise să aibă o copie a „Elementelor“ lui Euclid.

La vârsta de 14 ani, Blaise Pascal a început să-l însoţească pe tatăl său la întrunirile lui Mersenne de la Paris, la care participau Roberval, Auzout, Mydorge, Desargues, ultimul devenind un model pentru tânărul Pascal. Pe la vârsta de 16 ani, Blaise a prezentat la aceste întruniri câteva teoreme despre geometria proiectivă, incluzând hexagonul mistic al lui Pascal.În decembrie 1639, familia Pascal a părăsit Parisul pentru a locui la Rouen unde Etienne a fost numit colector de taxe pentru Normadia de Sus şi unde Blaise publică în februarie 1640 Essay on Conic Sections (Eseu despre secţiunile conice). După ce a lucrat 3 ani, între 1642 şi 1645, Pascal a inventat primul calculator mecanic, Pascaline pentru a-l ajuta pe tatăl său în munca sa de colector de taxe.În 1646 tatăl său s-a rănit la picior şi a trebuit să se recupereze acasă, în grija a 2 fraţi mai tineri dintr-o mişcare religioasă, care au avut o influenţă asupra tânărului Pascal care a devenit profund religios. Tot din această perioadă datează şi primele încercări de studii asupra presiunii atmosferice, iar in 1647 demonstrează că vidul există, după ce la 25 septembrie el şi Descartes s-au contrazis asupra acestui adevăr. În 1648 Pascal a observat că presiunea atmosferei scade cu înălţimea şi a dedus că vidul există deasupra atmosferei.În septembrie 1651, Etienne Pascal moare, iar într-o scrisoare adresată uneia din surori dă un adânc înţeles creştin morţii în general şi morţii tatălui său în particular, idei care formează baza pentru lucrării sale filozofice ulterioare, Les pensées.Din mai 1653, Pascal scrie Récit de la grande expérience de l'équilibre des liqueurs (Tratat despre echilibrul lichidelor) în care explică legea presiunii. În urma corespondenţei cu Fermat din vara anului 1654 a pus bazele teoriei probabilităţii. În această perioadă are şi probleme de sănătate, dar continuă lucrul până în octombrie 1654. Pe 23 noiembrie 1654, în urma unei experienţe religioase îşi dedică viaţa Creştinătăţii.După această dată, Pascal face vizite la mănăstirea Jansenistă Port-Royal des Champs la cca. 30 de km sud-vest de Paris şi publică lucrări anonime reunite în Lettres provinciales, în 1656. Între 1656 şi 1658 scrie Les pensées, cea mai cunoscută lucrare teologică a lui Pascal.Moare la 39 de ani pe 19 August 1662, în urma extinderii tumorii maligne din stomac şi este înmormântat St. Étienne-du-Mont în Paris.[modifică] Contribuţii în ştiinţă

Pascaline unul din primele calculatoare mecanice, lăsat după moartea lui Pascal lui Carcavi, unul din prototipuri aflându-se la muzeul Zwinger din DresdaLa vârsta de 16 ani Pascal a prezentat primul său rezultat original cunoscut sub numele de triunghiul lui Pascal (teorema lui Pascal), iar la 18 ani a construit primul calculator mecanic, pentru a-şi ajuta tatăl la calculul taxelor. Dispozitivul numit Pascaline, semăna cu un calculator mecanic al anilor 1840, iar această invenţie îl face pe Pascal a doua persoană care inventează calculatorul mecanic deoarece Schickard mai făcuse unul în 1624. Pascal se confruntă cu probleme de design ale calculatorului, datorate sistemului francez din acea vreme. Erau 20 de soli într-o livră şi 12 dinari într-un sol, astfel încât Pascal trebuia să rezolve probleme tehnice mult mai grele cu această împărţire a livrei în 240 decât dacă ar fi lucrat cu împărţirea la 100. Oricum producţia aparatelor a început în 1642, dar până în 1652 fuseseră produse 50 de prototipuri, însă puţine au fost vândute, şi producerea calculatorului aritmetic al lui Pascal a încetat în acel an. Unul din aceste prototipuri este la muzeul Zwinger, în Dresda Germania.Aflând de încercarea lui Torricelli de a determina presiunea atmosferică, Pascal a început să caute diverse tipuri de experienţe care să dovedească temeinicia descoperirii lui Torricelli, construind o instalaţie cu tuburi care demonstra influenţa presiunii. În august 1648 Pascal a observat că presiunea atmosferei scade cu înălţimea şi a dedus că vidul există deasupra atmosferei. Descartes îi scria lui Carcavi în iunie 1647 despre experimentele lui Pascal: „Eu am fost acela care l-am sfătuit acum doi ani sa facă aceasta, de aceea, deşi nu am participat eu însumi, nu m-am îndoit de succesul nostru...“, deşi cu un an înainte, în urma unei neînţelegeri cu Pascal cu privire la existenţa vidului îi scria lui Huygens că Pascal „... avea prea mult vid în capul său.“Pascal a fost primul care s-a gândit că, cu ajutorul barometrului, poate fi măsurată diferenţa de altitudine dintre două puncte şi a atras atenţia că modificarea lungimii coloanei de mercur mai depinde şi de umiditate şi temperatura aerului, putând fi folosită astfel în previziuni meteorologice. Nu mai puţin importante sunt lucrările lui Pascal din domeniul hidrostaticii. În lucrarea sa cea mai importantă „Tratat despre echilibrul lichidelor“ a formulat legea fundamentală a hidrostaticii, numită apoi legea lui Pascal. A calculat mărimea presiunii hidrostatice, a descris paradoxul hidrostatic, legea vaselor comunicante şi principiul presei hidraulice.El a lucrat la secţiunile conice şi a produs teoreme importante în geometria proiectivă. În „The Generation of Conic Sections (Generaţia secţiunilor conice)“, Pascal considera conurile generate de o proiecţie centrală a unui

cerc. Acesta era prima parte a tratatului asupra conurilor (pe care Pascal nu l-a terminat niciodată). Lucrarea este acum pierdută dar, Leibniz şi Tschirnhaus au notat din ea şi prin acestea este posibilă o imagine aproape completă a lucrării.Lucrarea lui Pascal asupra coeficienţilor binomiali l-a condus pe Isaac Newton la descoperirea teoremei binomului general pentru puteri fracţionare şi negative.Din corespondenţele cu Fermat se va naşte apoi teoria probabilităţilor, în urma unor întrebări adresate de cavalerul de Mére privind jocul de zaruri.Din 1654 abandonează însă lumea ştiinţifică pentru a se dedica Creştinătăţii, ultima sa lucrare publicată descriind curba trasată de un punct pe circumferinţa unui cerc care se învârte. Din 1658 începe din nou să se gândească la probleme de matematică din cauza durerilor care îi chinuiau somnul. Pascal îi provoacă pe Wren, Laloubère, Leibniz, Huygens, Wallis, Fermat cu două probleme : calculul ariei oricărui segment de cicloidă şi centrul de gravitate al oricărui segment, probleme pe care Pascal le rezolvase folosind calculul îndivizibililor al lui Cavalieri, în scrisorile către Carcavi.[modifică] Contribuţii în Filosofie şi TeologiePascal s-a ocupat şi de filozofie, considerând că progresul ştiinţific este scopul existenţei omenirii. Oscilând între raţionalism şi scepticism, el a ales spre finalul vieţii credinţa, fiind influenţat încă de mic de credinţa în Dumnezeu. De la vârsta de 14 ani, Blaise Pascal participa alături de tatăl său la întâlnirile abatelui de Mersenne, care aparţinea ordinului religios de la Minims, iar după ce tatăl său se răneşte la picior şi este îngrijit de doi fraţi ai unui ordin religios de lângă Rouen, Pascal devine profund religios. În urma unui accident suferit în 1654 pe podul de la Neuilly pe Sena, când caii, care trăgeau trăsura, au sărit şi trăsura a rămas agăţată de pod, dar mai ales în urma unei revelaţii religioase de pe 23 noiembrie 1654 Pascal a hotărât să ia calea credinţei, vizitând mănăstirea jansenită de lângă Paris.În acest domeniu Pascal îşi datorează faima atacului împotriva cazuisticii, o metodă folosită în special de iezuiţi, atac întreprins în Lettres provinciales. În acestă lucrare Pascal lua apărarea prietenului să jensenist Antoine Arnould, şi va aprinde mânia regelui Ludovic al XIV-lea care va da ordin să fie arsă.Cea mai cunoscută lucrare filosofică a lui Pascal este Les pensées, o colecţie de gânduri asupra suferinţei umane şi a încrederii în Dumnezeu, o lucrare apologetică creştină adresată noii lumi desacralizate. Această lucrare cuprinde şi celebrul pariu al lui Pascal, care încearcă să demonstreze că Dumnzeu există, folosidu-se de o teorie a probabilităţilor. Începută în corespondenţa cu Fermat pentru a demostra o problemă a jocului cu zarurile, Pascal presupune că toate cazurile apar „la fel de uşor”, pentru că Cineva, Supremul, avea grijă să le distribuie astfel. Pariul său era : „dacă Dumnezeu există şi sunt catolic, câştig viaţa veşnică, supunîndu-mă bisericii; dacă nu, nu am nimic de pierdut“. Concepţia lui Pascal era, în cuvinte puţine: Dumnezeu există pentru că este cel mai bun pariu, iar Pascal avea nevoie de existenţa lui Dumnezeu pentru a îndrepta din când în când dezordinea din Univers.Pascal a făcut speculaţii teologice şi asupra noţiunii de infinit, în timp ce Isaac Newton, Leibnitz (şi chiar el însuşi prin studiile sale asupra epicicloidei), puneau bazele calcului infinitezimal, din care apoi, scuturându-se de aura mistică, se va naşte Analiza matematică.[modifică] Lucrări publicate

Essai sur les coniques (1640) (Eseu despre secţiunile conice); Expériences nouvelles touchant le vide (Noi experimente cu privire la vid)(1647); Récit de la grande expérience de l'équilibre des liqueurs(Tratat despre echilibrul lichidelor)(1653); Traité du triangle arithmétique(Tratat asupra triunghiurilor aritmetice) (1654) Les provinciales (Correspondances 1656-1657) (Scrisori Provinciale) Élément de géométrie (1657) L'art de persuader (1657) Les pensées (1670, posthume) (Gânduri)

La Wikicitat găsiţi citate legate de Blaise Pascal.Adus de la http://ro.wikipedia.org/wiki/Blaise_Pascal

http://www.profamilia.ro/revista.asp?id=2004_04_06

BLAISE PASCAL: O TRESTIE GÂNDITOARERadu Capan

"Omul nu este decât o trestie, cea mai fragilă din natură: dar este o trestie gânditoare. Nu este nevoie ca universul întreg să se înverşuneze împotriva lui pentru a-l zdrobi. Un abur, o picătură de apă sunt de ajuns pentru a-l ucide. Dar chiar dacă universul întreg l-ar zdrobi, omul tot ar fi mai nobil decât cel care-l ucide..."

Acest fragment este probabil cel mai cunoscut dintre cugetările matematicianului, fizicianului, scriitorului, filosofului, misticului şi catolicului Blaise Pascal (1623-1662). Pentru majoritatea dintre noi, şcoliţi în regimul trecut, numele Pascal ne este asociat, în cel mai bun caz, cu două teorii: o lege fizică ce stă la baza hidrostaticii şi o teoremă matematică cu un hexagon înscris într-o conică. Acelaşi regim, într-un dicţionar enciclopedic apărut în anii '60, nota "moartea" lui Pascal în 1654, când "a abdicat de la raţiune în favoarea credinţei". Cine este acest Blaise Pascal, om al ştiinţei şi om al credinţei? Să încercăm să îl redescoperim în măsura în care ne-o permit câteva paragrafe. Blaise Pascal s-a născut la 19 iunie 1623, la Clermont. De mic a fost atras de matematică. Sora lui scrie despre micul Blaise că, "de îndată ce atinse vârsta la care i se putea vorbi, apărură semnele unei inteligenţe cu totul ieşite din comun, prin observaţiile pe care le făcea mereu în legătură cu orice, dar mai ales prin întrebările pe care le punea despre natura lucrurilor, întrebări care surprindeau pe toată lumea". Mama lui Blaise a murit când acesta avea doar trei ani, astfel încât sarcina educării lui a fost preluată de tatăl Etienne, care i-a acordat toată atenţia şi i-a încurajat interesul pentru descoperirea regulilor ascunse în spatele naturii. Deşi era evidentă genialitatea lui, Etienne a evitat să îl înveţe ceva înainte de a împlini vârsta la care ceilalţi învăţau aceasta. Strategia adoptată nu l-a oprit pe Blaise din studiu. Observaţiile lui porneau de la aspecte cât se poate de casnice, precum rezonanţa unei farfurii lovite cu cuţitul, diferită dacă farfuria era goală sau plină. La 12 ani ochii îi cad pe geometrie. Tatăl i-a explicat cu ce se ocupă geometria şi i-a arătat diverse forme geometrice, fără să le numească însă, pentru a nu-l implica în acest univers care, considera el, nu era de vârsta lui. Blaise, la locul lui de joacă, începe să deseneze cercuri, triunghiuri şi alte forme geometrice. Botează el cercul cu numele de rotund, iar linia cu numele de bară. Se străduieşte să deseneze cât mai perfect aceste forme, după care interesul i se mută în găsirea de proporţii, de reguli, de teorii în spatele formelor. Aşa se face că, într-una din zile, tatăl îl surprinde în timp ce se juca. Întrebându-l ce face, Blaise îi explică cu nonşalanţă o idee pe care tatăl lui o recunoaşte a fi o teoremă a lui Euclid. Vorbindu-i de rotunduri şi de bare, Blaise îi explică şi alte descoperiri de-ale lui.

"Creştinismul este ciudat. El porunceşte omului să-şi recunoască răutatea şi chiar caracterul lui abominabil; şi-i porunceşte să fie asemenea lui Dumnezeu. Fără o asemenea contrapondere, elevaţia l-ar face îngrozitor de vanitos, iar ticăloşia teribil de abject."

Progresele remarcabile ale lui Blaise continuă, iar la 19 ani el uimeşte din nou prin inventarea unei maşini aritmetice. Fără pană de scris şi hârtie, această maşinărie făcea calcule şi pentru prima oară scotea calculul matematic din "proprietatea" exclusivă a matematicienilor: acum şi oameni fără prea multă şcoală, folosind maşina aritmetică, puteau face calcule ce erau infailibile. În anii ce au urmat, Blaise a adus contribuţii valoroase în domeniul geometriei, al calculului infinitezimal, al teoriei numerelor, algebrei, calculului probabilităţilor. Dar încă dinainte de împlinirea vârstei de 20 de ani, în trupul său au apărut semnele unor boli care nu îl vor mai părăsi până la moarte. În următorii ani în viaţa lui are loc o schimbare majoră. Lecturile religioase îl apropie de Dumnezeu şi în suflet i se sădeşte ideea că viaţa nu are sens fără El. Lumescul îl interesează tot mai puţin, iar boala îl face să conştientizeze adevăratul loc al omului în universul creat. În această perioadă, pe când avea 23-24 de ani, îşi manifestă pentru prima oară interesul pentru mănăstirea austeră de la Port-Royal des Champs. Va rămâne însă departe de ea, datorită sfatului medicilor. Aceştia, pe motivul sănătăţii lui precare, i-au spus că viaţa la mănăstire nu i-ar face bine şi i-au recomandat să îşi petreacă timpul nu făcând eforturi intelectuale sau de alt gen, ci cu conversaţii lumeşti. "A fost partea din viaţa lui cea mai fără rost", scrie sora lui în "Viaţa domnului Pascal". În final Blaise se ruşinează că pe motivul sănătăţii şi-a dat atâţia ani lumii şi revine la hotărârea iniţială de a părăsi lumescul şi de a se dedica total lui Dumnezeu, în mănăstirea de la Port-Royal. O altă soră de-a lui intrase în mănăstire în 1662. El o va face în 1655, în anul următor unei experienţe ce i-a marcat pentru totdeauna viaţa. Despre ea lumea avea să afle însă abia după moartea lui Pascal, când în căptuşeala hainei lui un servitor a descoperit o hârtie scrisă de mână: "Luni, 23 noiembrie [1654], ziua sfântului Clement, papă şi martir, precum şi a altor martirizaţi", scria Blaise identificând ziua, după care descrie experienţa mistică: "De la ora zece şi jumătate seara până la ora douăsprezece şi jumătate în miez de noapte. Foc. Dumnezeul lui Avraam, Dumnezeul lui Isaac, Dumnezeul lui Iacob, nu al filosofilor şi al savanţilor. [...] Lepădarea de lume şi de toate, în afară de Dumnezeu. [...] Iar viaţa veşnică aceasta este ca să te cunoască pe tine, singurul, adevăratul Dumnezeu, şi pe Isus Cristos pe care l-ai trimis. M-am lepădat de El, l-am alungat, l-am tăgăduit; l-am răstignit. De El în veci să nu mai fiu despărţit. Şi El nu e de găsit decât pe calea arătată de Evanghelie. Întreagă şi mângâietoare renunţare. Supunere totală lui Isus Cristos şi duhovnicului meu."

"Dacă omul nu este făcut pentru Dumnezeu, de ce nu este fericit decât întru Dumnezeu? Dacă omul este făcut pentru Dumnezeu de ce îi este el atât de potrivnic lui Dumnezeu?"

Retras în mănăstire, Blaise şi-a luat două angajamente: să renunţe la toate plăcerile lumii, şi să renunţe la toate deşertăciunile. Iar un prim pas a fost renunţarea la servitori şi însuşirea unui regim alimentar drastic, motivat în parte şi de problemele sale de sănătate. Obiectul studiului lui a devenit acum Sfânta Scriptură, dar nu prin minte, ci prin inimă, după cum se exprima chiar el. Viaţa lui s-a întors total spre Isus Cristos şi şi-a făcut din rugăciune un obicei. Anii pe care i-a "pierdut" în lume au devenit motivaţia scrierii unei Apologetici creştine, prin care să demonstreze celor care ignoră credinţa, că există suficiente dovezi în sprijinul ei. Nu va ajunge să termine

lucrarea propusă, dar după el au rămas zeci de mici fragmente, de idei, ce au fost reunite într-un volum intitulat "Cugetări".

"Nu numai că nu-l putem cunoaşte pe Dumnezeu decât prin Isus Cristos, dar nici pe noi nu ne putem cunoaşte decât prin Isus Cristos. În afara lui Isus Cristos nu vom şti nici ce este viaţa noastră, nici ce este moartea noastră, nu-l vom cunoaşte pe Dumnezeu şi nici pe noi înşine."

Într-o confesiune găsită de sora sa pe o bucată de hârtie, Blaise scria: "Iubesc sărăcia pentru că o iubea şi Isus Cristos; îmi plac bunurile pentru că ele sunt de ajutor săracilor." Aceste cuvinte au avut acoperire în viaţa lui prin numeroasele fapte de milostenie, prin grija pe care o avea faţă de cei săraci. Nu refuza să dea pomană săracilor şi s-a întâmplat chiar să ajungă el la datorii pentru a-i ajuta pe cei nevoiaşi. Când i se reproşa că face donaţii prea mari, spunea: "Am remarcat un lucru şi anume că oricât de sărac ai fi, tot laşi ceva în urmă după ce mori." El nu dorea să lase nimic material în urma lui. Ultimii ani de viaţă au fost cumpliţi din punct de vedere fizic, neputând să doarmă luni întregi şi nici să mănânce prea mult. Cu gândul la apropiata moarte, deşi făcuse deja atâtea pentru săraci, îi spunea surorii lui: "Cum s-a întâmplat că n-am făcut nimic pentru săraci, cu toate că i-am iubit întotdeauna aşa de mult?" "Nu ai avut nici dumneata prea mult", i-a răspuns sora. "Dar atunci ar fi trebuit să le dau timpul meu şi grija mea; uite ce n-am reuşit să fac. Şi dacă medicii spun adevărul şi dă Dumnezeu să mă vindec de această boală, sunt hotărât să nu mă mai ocup de nimic decât să-i slujesc pe cei săraci." Medicii nu spuneau însă adevărul: moartea îi era aproape.

"Nu există decât două feluri de oameni: unii drepţi care se cred păcătoşi, alţii păcătoşi care se cred drepţi."

Ultimele zile le-a petrecut în pat, îngrijit cu atenţie, fapt care îi provoca mare durere, căci se simţea favorizat. A cerut să primească ultima Sfântă Împărtăşanie, dar medicii nu au fost de acord, spunând că nu este pe moarte. Blaise, ajuns la 39 de ani, simţea însă că Domnul îl cheamă. El le-a spus celor ce îl îngrijeau: "Pentru că nu vreţi să-mi faceţi această favoare [a Împărtăşaniei], aş vrea să o înlocuiesc cu o binefacere şi neputând intra în comuniune cu ceea ce se află Sus, aş vrea să intru în comuniune cu ceea ce se află jos. Iată de ce m-am gândit să-mi aduceţi lângă mine un bolnav căruia să i se dea aceleaşi îngrijiri ca şi mie, căci îmi este greu şi ruşine să fiu atât de bine îngrijit în timp ce o mulţime de săraci, cărora le este mult mai rău decât mie, sunt lipsiţi de aceste lucruri atât de necesare. Să i se aducă un infirmier şi să nu se facă nici o diferenţă între noi. Acest lucru îmi va uşura ideea că mie nu-mi lipseşte nimic, idee pe care nu o pot îndura dacă nu mi se aduce şi mângâierea de a şti că se află aici lângă mine un sărac la fel de bine tratat ca şi mine." Nu a mai fost nevoie. Durerile s-au înteţit şi în acea noapte sufletul lui Blaise Pascal s-a despărţit de trupul chinuit de boli. S-a stins din viaţă cu conştiinţa că moartea "lângă Isus Cristos este blândă, sfântă, aducând bucurie celui credincios", după cum îi spunea surorii lui.

http://www.romanialibera.ro/a152641/omul-ingramadire-de-contradictii.htmlOmul - ingramadire de contradictiiMihai VlasieJoi, 30 Aprilie 2009Exista o lupta intre filosofi: unii isi dau osteneala de a-l ridica pe om, descoperindu-i maretia, iar altii de a-l cobori, facandu-l sa-si vada decaderea - spune B. Pascal (fizician, scriitor si filosof francez, 1623-1662). Intr-o cugetare a sa, Pascal este si de o parte si de cealalta a filosofilor; ba mai mult, in aceeasi fraza pune fata-n fata si pe cele marete si pe cele josnice ale omului. Mai intai, intreaba cu multa asprime: "Ce himera mai e si acest om? Ce noutate, ce monstru, ce haos, ce ingramadire de contradictii?" si, mai departe, iata aceasta "ingramadire de contradictii" din fiinta umana: "Judecator al tuturor lucrurilor, imbecil vierme de pamant; depozitar al adevarului, ingramadire de incertitudine si de eroare; marire si lepadatura a Universului. Daca se lauda, eu il cobor; de se coboara, il laud si-l contrazic mereu pana ce reuseste sa inteleaga ca este un monstru de neinteles" (Blaise Pascal, "Cugetari", Ed. stiintifica, 1992).

Am ramas mirat si am zambit cu duiosie amintindu-mi de un cuvant al lui Pascal, pe care-l cunoaste si-l rosteste toata lumea cu gingasie, cand vine vorba de fiinta noastra: "Omul nu este decat o trestie, cea mai slaba din natura, dar este o trestie care gandeste". Dar iata ca in aceasta "trestie ganditoare" Pascal gaseste si insusiri ale omului atat de joase, de urate.

http://www.filosofieonline.com/citate.php?what=Blaise%20Pascal&sess_id=Blaise Pascal

BLAISE PASCAL (19 iunie 1623 – 19 august 1662) - matematician, fizician şi filosof al religiei –

Blaise Pascal s-a născut la Clermont pe 19 iunie 1623 şi a încetat din viaţă la Paris pe 19 august 1662. Tatăl său a fost judecător la Clermont şi savant renumit, care în 1631 s-a mutat la Paris. Educat acasă, în spirit cărturăresc uşor, ca să nu-l obosească prea mult, a învăţat iniţial limbile străine. La 12 ani, a întrebat ce este geometria şi tutorele său i-a răspuns că este ştiinţa construirii figurilor exacte şi a determinării proporţiilor dintre diferite părţi ale lor. Şi pentru că geometria nu figura printre materiile sale de studiu, a învăţat-o singur şi în câteva săptămâni a descoperit multe proprietăţi ale figurilor geometrice, în particular propoziţia potrivit căreia suma unghiurilor unui triunghi este egală cu două unghiuri drepte. Fascinat de această abilitate a fiului, tatăl i-a dat o copie a „Elementelor” lui Euclid, o carte pe care Pascal a citit-o cu lăcomie şi a început imediat să o proceseze. Astfel, înainte să împlinească 13 ani, a demonstrat cea de-a 32-a propoziţie a lui Euclid şi a descoperit o eroare în geometria lui René Descartes. La vârsta de 14 ani a fost admis la întâlnirile săptămânale la care participau Roberval, Mersenne, Mydorge şi alţi geometri francezi (prin eforturile lor a apărut Academia Franceză). La vârsta de 16 ani se pregătească să scrie un studiu al tuturor ramurilor matematicii, dar tatăl său îl solicita adesea să-i însumeze coloane lungi de numere. Astfel a ajuns, la 18 ani, să construiască o maşină aritmetică de calcul, pe care la 30 de ani a perfecţionat-o – „pascalina”. S-a născut primul calculator mecanic exact, dar care nu prea a avut căutare în epocă. La 16 ani a scris un eseu despre secţiunile conice, iar în 1641. Corespondenţa sa cu Fermat dina această perioadă arată că atenţia îi era atrasă spre geometria analitică şi fizică. A repetat experienţele lui Toricelli şi a confirmat teoria sa asupra cauzei variaţiilor barometrice. În 1650, la mijlocul acestor studii, a abandonat subit cercetarea, dedicându-se studiului religiei. În 1653, ocupându-se de afacerea tatălui său, a profitat de ocazie ca să facă mai multe experienţe de estimare a presiunii exercitate de gaze şi lichide; în această perioadă a inventat triunghiul aritmetic şi, împreună cu Fermat, a creat calculul probabilităţilor. Se gândea la căsătorie când un accident de circulaţie l-a făcut să se îndrepte spre o viaţă religioasă. S-a mutat la Port Royal. Renumitele sale „Scrisori provinciale”, îndreptate împotriva iezuiţilor şi „Gândurile” sale au fost scrise spre sfârşitul vieţii. Singura lucrare de matematică pe care a scris-o, după ce s-a retras la Port Royal, a fost un eseu despre cicloidă (1658). Suferea de insomnie şi îl durea cumplit o măsea atunci când i-a venit ideea şi, spre surprinderea lui, durerea a încetat imediat. Interpretând acest fapt ca pe o intervenţie divină, a lucrat fără pauză timp de opt zile la această problemă, aducând o contribuţie însemnată la studiul geometriei cicloidei. Dezamăgit de slaba reacţie a populaţiei la maşina sa aritmetică de calcul, Pascal a renunţat complet la ştiinţă şi matematică şi s-a devotat pentru tot restul vieţii credinţei în Dumnezeu. A încetat din viaţă la Port Royal, în 1662.

1, ' Cu cît esti mai întelept, cu atît îti dai mai bine seama ca pe lume exista multi oameni deosebiti. Oamenii de duzina nu observa nici o deosebire între semenii lor. ' ( xyz007k in data de 2003-06-15 ).

2, ' Inima are ratiuni pe care ratiunea nu le cunoaste. ' ( xyz007k in data de 2003-06-29 ).

3, ' Oamenii se corecteaza uneori mai bine cand vad raul decat cand vad binele; si este bine sa ne obisnuim a profita de rau, mai ales ca il gasim atat de des: binele, din contra, este foarte rar. ' ( Adrian C. in data de 2004-12-19 ).

4, ' Intr-un suflet mare, totul este mare, iar intr-un suflet mediocru, totul este mediocru; pritenia ca si toate celelalte. ' ( xyz007k in data de 2003-07-04 ).

5, ' Omul e trestia cea mai slaba din natura, dar e trestie ganditoare ' ( xyz007k in data de 2003-07-04 ).

6, ' omul este pentru el insusi obiectul cel mai uimitor din natura ' ( pinki in data de 2005-04-17 ).

7, ' Dreptatea fara forta e neputincioasa, forta fara dreptate e tiranica! ' ( magiaru in data de 2005-09-02 ).

8, ' We are usually convinced more easily by reasons we have found ourselves than by those which have occurred to others. ' ( Mariana Fulger in data de 2006-02-21 ).

9, ' Man is equally incapable of seeing the nothingness from which he emerges and the infinity in which he is engulfed. ' ( Mariana Fulger in data de 2006-02-21 ).

10, ' We run carelessly to the precipice, after we have put something before us to prevent us from seeing it. ' ( Mariana Fulger in data de 2006-02-21 ).

11, ' Few men speak humbly of humility, chastely of chastity, skeptically of skepticism. ' ( Mariana Fulger in data de 2006-02-21 ).

12, ' When we encounter a natural style we are always surprised and delighted, for we thought to see an author and found a man. ' ( Mariana Fulger in data de 2006-02-21 ).

13, ' Everything that is written merely to please the author is worthless. ' ( Mariana Fulger in data de 2006-02-21 ).

14, ' I cannot judge my work while I am doing it. I have to do as painters do, stand back and view it from a distance, but not too great a distance. How great? Guess. ' ( Mariana Fulger in data de 2006-02-21 ).

15, ' Contradiction is not a sign of falsity, nor the lack of contradiction a sign of truth. ' ( Mariana Fulger in data de 2006-02-21 ).

16, ' Perfect clarity would profit the intellect but damage the will. ' ( Mariana Fulger in data de 2006-02-21 ).

17, ' Those who are accustomed to judge by feeling do not understand the process of reasoning, because they want to comprehend at a glance and are not used to seeking for first principles. Those, on the other hand, who are accustomed to reason from first principles do not understand matters of feeling at all, because they look for first principles and are unable to comprehend at a glance. ' ( Mariana Fulger in data de 2006-02-21 ).

18, ' To deny, to believe, and to doubt well are to a man as the race is to a horse. ' ( Mariana Fulger in data de 2006-02-21 ).

19, ' Words differently arranged have a different meaning and meanings differently arranged have a different effect. ' ( Mariana Fulger in data de 2006-02-21 ).

20, ' Nature is an infinite sphere of which the center is everywhere and the circumference nowhere. ' ( Mariana Fulger in data de 2006-02-21 ).

21, ' We arrive at truth, not by reason only, but also by the heart. ' ( Mariana Fulger in data de 2006-02-21 ).

22, ' We are so presumptuous that we should like to be known all over the world, even by people who will only come when we are no more. Such is our vanity that the good opinion of half a dozen of the people around us gives us pleasure and satisfaction. ' ( Mariana Fulger in data de 2006-02-21 ).

23, ' The sole cause of man's unhappiness is that he does not know how to stay quietly in his room. ' ( Mariana Fulger in data de 2006-02-21 ).

24, ' The more I see of men, the better I like my dog. ' ( Mariana Fulger in data de 2006-02-21 ).

25, ' Man is but a reed, the most feeble thing in nature, but he is a thinking reed. The entire universe need not arm itself to crush him. A vapor, a drop of water suffices to kill him. But, if the universe were to crush him, man would still be more noble than that which killed him, because he knows that he dies and the advantage which the universe has over him, the universe knows nothing of this. ' ( Mariana Fulger in data de 2006-03-06 ).

26, ' All our dignity then, consists in thought. By it we must elevate ourselves, and not by space and time which we cannot fill. Let us endavour then, to think well; this is the principle of morality. ' ( Mariana Fulger in data de 2006-03-06 ).

http://www.didactic.ro/files/3/cei_doi_pascal.docCei doi PASCAL

Etiennne Pascal(1588 – 1651)

Magistrat şi matematician francez, tatăl lui Blaise Pascal şi poate că în principal acesta este şi motivul celebrităţii sale în istoria ştiinţei ( cum se mai spune deseori „părinţi ai unor copii celebri”). L-a crescut pe Blaise într-un spirit foarte riguros şi intuind calităţile virtuale ale fiului său pe care îl adora, a renunţat la slujbă pentru a se consacra educaţiei şi pregătirii acestuia. L-a învăţat geografia, istoria, filosofia, limbile străine şi matematica. A căutat să nu-i încarce fiului său mintea cu o serie întreagă de date brute, fără o semnificaţie importantă, străduindu-se să-l înveţe în esenţă capacitatea de a gândi cu capul lui, mai degrabă decât să-i supună memoria cu exerciţii inutile.

În confesiunile lui, Blaise Pascal mărturisea că începând de la vârsta de 18 ani n-a cunoscut în scurta sa viaţă nici o zi în care mintea lui să stea liniştită, stare în care ajunsese şi datorită programului impus din copilărie de tatăl său. Mărturisea de asemenea că, în ciuda admiraţiei şi recunoştinţei care le avea pentru tatăl său, acesta l-a izolat de ceilalţi copii şi l-a închis întrucâtva într-un fel de închisoare a minţii, care era antrenarea intensivă la care îl supusese. Aceasta a declanşat fără îndoială geniul excepţional al lui Blaise, făcându-i celebri pe amândoi, dar a dăunat tot odată constituţiei sale, nepermiţându-i să ajungă la o trăire deplină a vieţii.

În matematică Etienne Pascal a avut diferite preocupări şi rezultate care nu au rămas peste veacuri, cu excepţia unor curbe de ordinul patru având denumirea de melcii lui Pascal, denumire dată de Roberval (1602 – 1675) în memoria lui Etienne, probabil descoperitor. Definirea lor se face astfel: dacă O este un punct fix pe cerc şi M un punct mobil pe cerc, pe secanta OM purtăm de o parte şi de alta segmentul MP de lungime l constantă. Atunci punctul P descrie melcul lui Pascal, care are diferite forme după cum l este mai mic, egal sau mai mare decât diametrul cercului. ( Cazul intermediar, când l este egal cu diametrul cercului corespunde curbei numita cardioidă, studiată printre alţii şi Roberval).

Blaise Pascal (19.06.1623 – 19.08.1662)

Matematician, fizician şi filosof francez, născut la Clermont – Ferrand, a cărui precocitate în lumea ştiinţei rămas celebră în istoria ştiinţei. A fost instruit numai de tatăl său. El nu a urmat nici o şcoală şi nici-o universitate! În 1634, la vârsta de 11 ani, alcătuise deja un Tratat al sunetelor sub îndrumarea stimulatoare a tatălui său. La vârsta de 12 ani regăsea prin studiile sale 32 de propoziţii ale lui Euclid (330 – 275 i. Hr.), la 16 ani a compus un tratat asupra secţiunilor conice, iar la 19 ani a construit o maşină de calcul ( învăţând şi observând atent munca plicticoasă pe care tatăl său era constrâns să o facă în calitate de încasator de impozite în cadrul Administraţiei franceze, Blaise Pascal căuta un mijloc de a-l ajuta şi astfel apare socotitoarea mecanică (1642) numită pascaliana prima maşină de calcul din lume), realizări care marcau începutul furtunos al unei celebrităţi, care ca în multe alte cazuri de genii, a avut o viaţă scurtă (doar 39 ani).

A construit un orologiu (se spune că lui i se datorează ideea de a purta ceasul la mână), iar spre sfârşitul vieţii a construit un omnibuz, invenţie deosebit de spectaculoasă, care s-a bucurat de multă popularitate.

Ca fizician a emis principiul care îi poartă numele (legea lui Pascal) privind transmiterea presiunii prin fluide ( principiul hidrostaticii).

În matematică cercetările sale sunt legate de domeniile teoriei numerelor, algebrei, analizei şi calculul probabilităţilor, având în toate direcţiile contribuţii fundamentale deşi a fost mai toată scurta sa viaţă bolnav, neputându-se dedica cercetării ştiinţifice mai mult de un deceniu.

În teoria numerelor nu a creat mult (ca număr de lucrări). Din corespondenţa sa cu P. Fermat (1601 – 1665), au reieşit două lucrări datând cam de pe la 1654, dar publicate abia în 1665. În una din ele a studiat factorialul

a(a+1)(a+2)…(a+k-1)cu a şi k întregi, stabilind şapte teoreme referitoare la acesta. Cercetările sale vor fi reluate în secolul următor de Euler (1707 - 1783), Lagrange (1736 - 1813) şi alţii, reliefându-se astfel ingeniozitatea matematică a lui Pascal care l-a călăuzit spre un domeniu deosebit de important. Cealaltă lucrare conţine o justificare a regulii de stabilire a divizibilităţii unui număr printr-un număr arbitrar dat.

Tot în acest an 1654, Pascal i-a transmis lui Fermat Tratatul despre triunghiul aritmetic (apărut postum la Paris în 1665). În această lucrare, ca şi în Tratat despre ordinele numerice, apărut tot în 1665 pentru prima oară, sunt scoase în relief contribuţiile fundamentale ale lui Pascal în domeniul analizei combinatorii. Aici erau date relaţiile fundamentale dintre coeficienţii binomiali, pe care el îi identificase cu combinările şi cu care opera în acest sens. Triunghiul lui Pascal şi legea aditivă de formare a elementelor sale fuseseră cunoscute în India cam cu două secole î. Hr. Un tabel al coeficienţilor binomiali până la puterea a opta se întâlneşte în 1303, la

matematicianul chinez Ciju Şi-ţze(sec. 13 - 14), care a avut predecesori în secolul 12. Teorema generală a dezvoltării binomului în cazul unui exponent natural apare pentru prima dată la al-Kaşi (sec. 14 – 15), dar se pare că era cunoscută încă de Omar Khayyam (1048 - 1123) în secolul al 12 –lea. Pascal a ajuns la triunghiul aritmetic independent de Stifel (1487 - 1567) şi i-a dat o altă aşezare. Se mai spune că în timp ce scrisoarea lui Pascal era pe drum spre Fermat, venea la Fermat pentru Pascal un memoriu consacrat unor probleme înrudite şi anume, cu privire la numerele figurative (triunghiulare, patrulatere,…, poligonale), care reprezentau termeni ai unor şiruri de diferenţe finite de ordin superior erau scrise de Fermat într-o formă de produse, a căror echivalenţă de azi este aceea a combinărilor exprimate prin factoriale. Cuvântul combinare în sensul de astăzi îi aparţine lui Pascal. Pentru a demonstra teoremele referitoare la coeficienţii binomiali, Pascal a mai făcut o descoperire fundamentală, introducând metoda inducţiei complete (nu se ştie dacă el a fost influenţat în descoperire de Maurolico (1494 - 1575), care folosise metoda încă din 1575). În mod independent, Jacques I Bernoulli (1654 - 1705) a descoperit această metodă în 1686, adică peste treizeci de ani de la Pascal.

O dată cu analiza combinatorie, în corespondenţa dintre Pascal şi Fermat (1654) a mai fost fondată o nouă ştiinţă, aceea a calcului probabilităţilor. Punctul de plecare a fost o problemă care apare în jocul de zaruri, pusă încă din 1494 de Luca Picioli (1445 - 1514) şi studiată, fără succes, de Cardano (1501 - 1576) în 1539 şi Tartaglia ( N. Fontana, 1500- 1557) în 1556. Soluţia corectă, dar greoaie, pentru această problemă (a repartiţiei echitabile a mizei între jucători, pe care trebuie să o capete unul dintre ei după ce va fi însumat un anumit număr de puncte în cazul în care jocul se întrerupe înainte ca unul dintre parteneri să atingă acest număr de puncte) a fost dată de Pascal şi va fi confirmată de Fermat, care obţinuse acelaşi rezultat, dar pe altă cale, mai simplă. Pascal nu a putut însă să extindă rezultatul la cazul cu mai mult de doi jucători, rezultat pe care îl va obţine Huygens (1629 - 1695) şi apoi Jacques I Bernoulli.

În anul 1658, Pascal lansa o provocare tuturor matematicienilor asupra ruletei (problema cicloidei), curbă pe care a studiat-o mai ales cu ajutorul metodei indivizibililor pe care a pus-o admirabil la punct. Mult mai consecvent decât profesorul său Roberval (1602 - 1675), Pascal, îndemânat şi de metoda de demonstraţie a lui Gregorius a St. Vincentio (1584 - 1667), a reuşit să transforme noţiunea de totalitate a lui Cavalieri (1598 – 1647) în noţiunea de sumă. Aici Pascal a făcut o distincţie neta între indivizibili şi părţile elementare şi a dat o interpretare esenţialmente mai generală noţiunii de egalitate a figurilor decât permitea definiţia euclidiană uzuală pe atunci. El considera că două figuri sunt egale dacă diferenţa dintre ele este mai mică decât orice mărime apriori dată.

El pătrundea cu multa claritate în esenţa procesului de integrare, observând că fiecare integrare se reduce la determinarea anumitor sume aritmetice. Încă din 1654, în lucrarea Suma puterilor numerelor ce va apare în 1665 la Paris, el declara că pentru toţi cei ce se orientează câtuşi de puţin în teoria indivizibilior, trebuie să fie clară dependenţa dintre sumele puterilor şi măsurarea ariilor curbilinii. El s-a apropiat mai mult decât toţi contemporanii săi de noţiunea de integrală definită, dar nedispunând de nici un simbol, el exprima totul în cuvinte. Articolele lui pe această temă, din 1659, erau foarte bogate în rezultate particulare ce conţineau calculul integralelor mai multor funcţii trigonometrice şi al unor integrale de forma

(în scrierea noastră). El a mai demonstrat în lucrările sale, de ademenea, o serie de teoreme privind, ceea ce numim astăzi, schimbarea de variabilă şi integrarea prin părţi. Reluând şi analizând în mai multe rânduri triunghiul caracteristic al lui Wallis (1616 - 1703) în 1656 (denumirea aparţinându-i lui Leibniz(1646 – 1716)), descoperire mare cu care autorul nu a ştiut ce să facă, Pascal a făcut ipoteza că elementul de arc considerat ca segment de dreaptă coincide cu tangenta şi în Tratat despre sinusurile sfertului de cerc (Paris, 1659), a dedus o egalitate ce exprima raportul a două elemente infinit de mici prin raportul a două mărimi finite. Rezultatul şi mai ales desenul după care Pascal a obţinut acest rezultat, i-au permis lui Leibniz să creeze ceea ce Pascal nu a putut (sau mai corect nu a avut timp să finalizeze) şi anume calculul diferenţial. Leibniz însuşi spunea că a zărit aici o lumină pe care autorul desenului nu o văzuse.

Cu toate ideile genial – spectaculoase pe care le-a avut, neavând timp să finalizeze, Pascal, rămâne doar un precursor al calculului diferenţial şi integral, realizarea acestor fapte asigurând celebritatea lui Leibniz şi Newton (1643 - 1727).

Începută furtunos, agitata lui viaţă avea să se termine la fel. A creat şi a avut idei din copilărie, la o vârsta când de regulă copiii se joacă. A plecat din lume la 39 de ani cu multe idei expuse şi nefinalizate aşa cum ar fi dorit, aşa cum s-a întâmplat cu planul lucrării despre conice, conceput la 16 ani şi la care mai lucra încă în

1654 (deci peste 15 ani), dorind să realizeze o operă amplă pe baza creată de Desargues (1593 – 1662). Manuscrisul, pe care Leibniz îl cunoscuse, s-a pierdut, aşa cum s-au pierdut şi importantele lucrări ale lui Desargues, ale cărui idei şi noţiuni au fost pe deplin asimilate şi dezvoltate numai de Blaise Pascal. Este meritul lui Leibniz de a fi lăsat posterităţii câteva note asupra marii lucrări a lui Pascal ale cărei idei fundamentale apăruseră în 1640 sub forma unui afiş intitulat Încercare asupra secţiunilor conice. După Leibniz, demonstraţia, cunoscută şi azi, a teoremei lui Pascal, despre cerc şi despre secţiunea conică generală, este cea dată de Pascal.

Între 1651 şi 1654 Pascal a frecventat societatea „oameni oneşti” unde a luat cunoştinţă despre importanţa artei de a agrea (arta de a seduce şi penetra spiritele) care se regaseste în Discurs asupra pasiunilor dragostei pe care unii i-o atribuie.

Sub influenţa surorii sale Jacqueline (1625 – 1661) devenită călugăriţă, a unor evenimente în care el a văzut opera Providenţei şi bulversat de extazul sau din 23 noiembrie 1654 (Memorialul), Pascal s-a retras la mănăstirea de maici Port – Royal de Champs. Aici s-a apropiat de grupul jansenist (adversari ai oricărui compromis) pe care îi va apăra în 18 scrisori polemice denumite Les Provinciales. Scrierile sale Les Provinciales (1656 – 1657) şi Pensées (1568) îl situează printre marii literaţi ai Franţei, gândirea sa profundă şi sclipitoare acoperind nu numai matematica sau fizica, ci şi arta şi filosofia. El sublinia, printre altele, despre matematică, faptul că „obiectul matematicii este atât de serios încât este util să nu pierdem ocazia pentru a-l face puţin mai distractiv”. Despre univers, nota că „universul este un cerc al cărui centru este pretutindeni, iar circumferinţa nicăieri”. În Pensées, lucrare memorabilă în domeniul filosofiei, Pascal a dat o definiţie excepţională a omului şi anume: „Omul nu e decât o trestie, cea mai fragilă din natură, dar o trestie gânditoare”.

http://referat.clopotel.ro/Blaise_Pascal-14358.htmlBLAISE PASCAL

Putini savanti au fost atat de controversati ca Pascal. Personalitatea sa stiintifica exceptionala a atras atat in timpul vietii sale, cat si in cele trei secole ce s-au scurs de la moartea sa, atentia multor cercetatori. Elogii, critici, denigrari, s-au amestecat intr-o gama cat se poate de larga. Blaise Pascal s-a nãscut pe 19 iunie 1623 în Clermont, intr-o familie cu vechi traditii intelectuale. Din partea mamei se inrudea cu marele scriitor Corneille. Documente pretioase ramase de la sora sa, Gilberte Perier cat si de la fiica acesteia, Marguerite ne ofera informatii asupra copilariei marelui savant. Inca de la o varsta frageda, Pascal a manifestat o inteligenta extraordinara, surprinzandu-i pe cei mari mai ales prin intrebarile pe care le punea asupra naturii lucrurilor. In 1626, cand Blaise avea doar 3 ani, a murit mama sa, iar tatal a ramas singur cu cei trei copii si a inceput sa se ocupe mai indeaproape de educatia acestora. Fata de cele doua fete, Gilberte si Jaqueline, l-a preferat pe Blasie, a carui inteligenta deosebita a remarcat-o curand. Blasie nu a intrat niciodata in vreun colegiu, ci l-a avut ca educator doar pe tatal sau. In 1632, tatal sau, judecãtor in Clermont, având la rândul sau un anumit renume în ştiinţa, s-a mutat în Paris, pentru a-si continua propriile studii pe o parte, si pentru a-şi educa unicul sãu fiu care dovedise deja abilitãti excepţionale, profitand de posibilitatile favorabile oferite de Paris pentru educatia acestuia. Tatal sau pune in aplicare un adevarat plan de educatie, avand drept principiu sa nu il incarce pe copil cu nimic din ceea ce nu ar putea intelege cu toata usurinta si in toata adancimea. Astfel el a amanat studiul sistematic al limbii latine si grecesti pe care il considera prima treapta a educatiei pana la varsta de 12 ani, urmand ca studiul matematicii sa inceapa dupa aceasta varsta. De la varsta de 8 ani pana la 12 ani Blasie a primit doar notiuni generale, in masura sa ii stimuleze interesul pentru disciplinele ce urmau sa fie ulterior aprofundate.Acest program a simulat curiozitatea băiatului şi, într-o zi, la 12 ani, baiatul a întrebat ce este geometria.Geniul sau geometric a inceput sa se manifeste de la aceasta varsta, incepand sa studieze geometria, sacrificandu-si timpul de joaca în ciuda restrictiilor care îi erau impuse, si in cateva saptamani descopera singur multe proprietati ale figurilor. Cea mai importantă este aceea privitoare la suma unghiurilor unui triunghi care este egala cu doua unghiuri drepte, respectiv 180 de grade. Se pare ca dovada consta simplu in impaturarea unghiurilor peste figura astfel încat varfurile lor să se intalneasca in centrul cercului inscris in triunghi. O demonstratie similara se poate obtine prin impaturarea unghiurilor astfel incat ele sa se intalneasca pe piciorul perpendicularei duse din varful unghiului cel mai mare pe latura opusă. Impresionat de aceasta demonstratie inteligentă, tatăl său i-a dat o copie a cărtii „Elementele” de Euclid, pe care Pascal o citeste cu interes pânã cand o invata.

Citind cartea, el isi da seama ca nu are nevoie de vreo explicatie. In timp ce citea compunea si progresa atat de mult, incat putea frecventa toate conferintele care se tineau saptamanal si la care se adunau oameni cu experienta in domeniu din Paris pentru a-si prezenta lucrarile sau pentru a le examina pe ale altora. Rezultatul educatiei oferite de tatal sau a fost ca Pascal poseda bine in scris si citit limba latina, cunostea greaca si se descurca si cu limba italiana. Mai important este faptul ca a devenit un scriitor de talent. Mai tarziu si-a insusit si cunostinte teologice si filozofice tot prin lectura. In orice caz, Blaise nu avea sa devina un erudit ci un amator genial. La varsta de paisprezece ani este admis la intalnirile saptamanale tinute de Roberval, Mersenne, Mydorge si de alti matematicieni francezi. In final, din aceste sedinte se naste Academia Franceza. La varsta de saisprezece ani, Pascal scrie un eseu despre conice, iar la optsprezece ani construieste prima masins aritmetica, un calculator rudimentar, pe care o va imbunati peste opt ani. In „Cugetari” , el delimiteaza posibilitatile masinii aritmetice, pronuntandu-se astfel: „Masina aritmetica produce efecte care se apropie mai mult de gandire decat tot ce fac animalele, dar nu face nimic ce ne-ar putea determina sa spunem ca ea are vointa ca animalele” Pentru realizarea planului sau, Pascal a inceput sa lucreze cu toata ardoarea tineretii. Dar, pe cat parea de simplu principiul, pe atat de mari erau piedicile pe care avea sa le intampine. Dificultatea cea mai mare era gasirea unor meseriasi in stare sa indeplineasca o asemenea munca si care sa ii urmeze exact indicatiile. Ei trebuiau sa posede perfect practica strunjirii, a pilei si a ciocanului pentru a reduce piesele masinii la pasurile si proportiile cerute de teorie. In 1642 nu construise decat un singur model, si acesta imperfect, astfel pronuntandu-se sa renunte la proiect. A avut insa noroc cu cancelarul Seguier, care, fiind informat de aceste incercari, l-a incurajat sa isi continue eforturile. Aceleasi indemnuri le-a primit si din partea lui Robeval. Astfel, Pascal si-a reluat proiectul si a trebuit sa depuna un efort considerabil pentru a construi „mai bine de 50 de modele, compuse din vergele sau lamele drepte, altele curbe, altele cu lanturi, unele miscandu-se im linie dreapta, altele circular, unele conice, altele cilindrice, iar altele cu totul diferite de acelea, fie prin material, fie prin forma” („Oeuvres de Pascal” – vol. II) In 1650, la mijlocul carierei lui stiintifice, Pascal si-a abandonat brusc idealurile lui in favoarea religiei, asa cum zice in Pensées, "contempleaza maretia si misterul omului". In 1653 a trebuit sa administreze mosia tatalui sau. Acum a adoptat iarasi vechile lui ocupatii si a facut cateva experimente asupra presiunii exercitate de lichide si gaze. In aceeasi perioada a inventat triunghiul aritmetic, si impreuna cu Fermat a creat calculul probabilitaţilor. Medita asupra casatoriei cand un accident l-a determinat iarasi sa se concentreze asupra religiei. S-a mutat la Port Royal unde a trait pana in 1662. Singura lucrare matematica pe care o mai scrie este un eseu despre cicloida in 1658. Suferea de insomnie si de o durere de dinti cand i-a venit ideea si spre surprinderea lui, suferinta i-a trecut. Privind aceasta ca un semn divin a continuat problema, lucrand fara oprire opt zile, si a terminat o lucrare relativ completa despre geometria cicloidei. Incepand cu 1660, Pascal nu mai manifesta nici o atractie fata de stiinta. Putina energie ramasa o cheltuieste pe meditatii religioase n redactarea unor note asupra religiei crestine. Aceasta abandonare a unor preocupari care au dat roade imbelsugate se explica prin boala necrutatoare care il chinuia, inainte de a-l distruge. Intr-o scrisoare catre Fernat, din 10 august 1660, se plange ca nu poate face mai mult de 3 sau 4 leghe in trasura, nu poate merge fara baston si nu poate calari. Starea sa sufleteasca este corespunzatoare acestei stari trupesti, iar in anul 1663, pe data de 13 august inceteaza din viata. Dupa moartea sa au fost gasite printre hartiile ramase note din lucrarea proiectata asupra religiei. Ele au fost puse in ordine de Gilberte Perier impreuna cu ducele de Roannez, Arnauld si au fost publicate in 1670 sub titlul: „Pensėes de M. Pascal sur la religion et sur quelques sujets” (Cugetarile d-lui Pascal asupra religiei si altor subiecte)

http://www.studentie.ro/Referat_BLAISE_PASCAL-nr13636-1.htmlBlaise Pascal

Dintre contemporanii lui Descartes, nici unul nu a arãtat un geniu natural mai bine decât Pascal. Reputatia lui în matematicã constã mai mult în ceea ce ar fi putut face decât in ceea ce a fãcut efectiv, deoarece o lungã perioadã din viatã a considerat cã datoria lui este de a se concentra asupra exercitiilor religioase.

Blaise Pascal s-a nascut pe 19 iunie 1623 în Clermont şi a murit la Paris în 19 august 1662. Tatal lui, un judecator din Clermont, având la rândul sau un anumit renume în ştiinţa, s-a mutat în Paris în 1631, pentru a-şi continua propriile studii pe o parte, şi pentru a-şi educa unicul sau fiu care dovedise deja abilitati excepţionale.

Micul Blaise a fost ţinut acasa pentru nu se obosi prea mult şi din acelaşi motiv educaţia lui a fost mai întâi restrânsã la învaţarea limbilor straine, neincluzând evident matematica. Acest program a simulat curiozitatea bãiatului şi, într-o zi, la doisprezece ani, a întrebat ce este geometria. Învaţatorul lui i-a raspuns ca este ştiinta construirii figurilor exacte şi a determinarii proportiilor dintre diferite parţi ale lor. În curând Pascal se apuca de studiat geometria, sacrificându-şi timpul de joaca şi în ciuda restrictiilor care îi erau impuse, şi în câteva saptamâni descopera singur multe proprietãti ale figurilor. Cea mai importantã este aceea privitoare la suma unghiurilor unui triunghi care este egalã cu douã unghiuri drepte, respectiv 180 de grade. Se pare cã dovada consta simplu în împãturarea unghiurilor peste figurã astfel încât vârfurile lor sã se întâlneascã în centrul cercului înscris în triunghi. O demonstratie similarã se poate obtine prin împãturarea unghiurilor astfel încât ele sã se întâlneascã pe piciorul perpendicularei duse din vârful unghiului cel mai mare pe latura opusã. Impresionat de aceastã demonstratie inteligenţa, tatãl sãu i-a dat o copie a cãrtii Elementele de Euclid, pe care Pascal o citeşte cu interes pâna când o învatã.La vârsta de paisprezece ani este admis la întâlnirile sãptãmânale tinute de Roberval, Mersenne, Mydorge şi de alţi matematicieni francezi. În final din aceste şedinţe se naşte Academia Franceza. La vârsta de şaisprezece ani Pascal scrie un eseu despre conice, iar la optsprezece ani construieşte prima maşina aritmetica, un calculator rudimentar, pe care o va îmbunãtãţii peste opt ani. Scrisorile lui catre Fermat arata ca aproximativ în aceasta perioada se concentra asupra geometriei analitice şi fizicii. A repetat şi experimentele lui Toricelli.În 1650 la mijlocul carierei lui ştiinţifice, Pascal şi-a abandonat brusc idealurile lui în favoarea religiei, aşa cum zice în Pensées, "contempleazã mãretia şi misterul omului". În 1653 a trebuit sa administreze moşia tatalui sau. Acum a adoptat iaraşi vechile lui ocupatii şi a facut câteva experimente asupra presiunii exercitate de lichide şi gaze. În aceeaşi perioada a inventat triunghiul aritmetic, şi împreuna cu Fermat a creat calculul probabilitatilor.Medita asupra casatoriei când un accident l-a determinat iaraşi sa se concentreze asupra religiei. S-a mutat la Port Royal unde a trãit pânã în 1662.Singura lucrare matematica care o mai scrie o a fost un eseu despre cicloida în 1685. Suferea de insomnie şi de o durere de dinti când i-a venit idea şi spre surprinderea lui suferinţa i-a trecut. Privind aceasta ca un semn divin a continuat problema, lucrând fara oprire opt zile, şi a terminat o lucrare relativ completa despre geometria cicloidei.Prima lucrare asupra geometriei conicilor, scrisã în 1639, a fost publicata doar în 1779. Conica este o curbã planã rezultatã din intersectia unui con circular cu un plan. Se pare ca a fost scrisa sub îndrumarea lui Desargues. Doua rezultate sunt deopotriva importante şi interesante. Primul este o teorema cunoscuta sub numele de Teorema lui Pascal :Dacã un hexagon poate fi înscris într-o conicã atunci punctele de intersectie ale laturilor opuse vor fi colinieare (pe aceiaşi dreapta). A doua care i se datoreaza în mare parte lui Desargues spune urmatoarele: Dacã un patrulater poate fi înscris într-o conica şi ducem o dreapta care intersecteaza laturile în A, B ,C respectiv D, şi conica în P şi Q atunci: .Pascal şi-a îmbunatatit triunghiul aritmetic în 1653, dar nu exista nici o consemnare a metodei lui pâna în 1665. Triunghiul este o figura simpla (ca cele doua şi se poate continua la infinit). Fiecare linie este formata din numere egale cu suma numerelor din stânga pozitiei de pe linia precedentã. De exemplu 20=1+3+6+10. Daca aşezam triunghiul altfel (ca în dreapta) este mai uşor sa vedem ca un numar este egal cu suma celor doua numere de deasupra lui, respectiv suma dintre numarul din stânga şi cel de deasupra în prima figura. vârful triunghiului fiind 1. Cele douã reguli sunt echivalente.

Numerele unei linii se numesc numere figurate. Primele se numesc numere de ordinul întâi, cele din a doua linie numere de ordinul doi, cele din a treia linie numere de ordinul trei ş.a.m.d. Se poate uşor demonstra ca a m-lea numãr de pe al n-lea rând este: .Triunghiul se obţine, în cazul primei figuri, trasând o diagonala în jos din colţul dreapta sus. Numarul pe fiecare diagonalã dau coeficientii binomiali al unei dezvoltãri, sunt coeficientii binomiali ai binomului lui Newton. De exemplu a cincia diagonalã 1, 4, 6, 4, 1 sunt coeficientii binomiali ai dezvoltãrii (a+b)4 . Pascal a folosit triunghiul pe de-o parte pentru diferite calcule proprii şi pe de alta parte pentru a calcula combinari de m luate câte n pentru cate a gasit formula corectã: .Probabil ca matematician Pascal este cel mai bine cunoscut pentru corespondenţa lui cu Fermat din 1657 în care a stabilit principiile probabilitaţii. Totul a pornit de la o problema propusã lui Pascal de un jucãtor numit Chavalier de Méré (Cavalerul Marii). La rândul sãu acesta i-a transmis-o lui Fermat. Problema era urmatoarea: Doi jucatori de valori egale vreau sa plece de la masa înainte de a termina o partida. Daca se cunoaşte scorul (în puncte) şi numarul de punctelor pâna la care vroiau sa joace (adica numarul turelor daca o tura câştigata

înseamnã un punct) se cere sã se afle în ce proportie trebuie sa împarta miza. Fermat şi Pascal au dat acelaşi raspuns dar demonstrati diferite. Urmãtoarea este demonstratia celui din urmã:Aceasta este metoda mea de a determina partea fiecãrui jucãtor când, de exemplu, doi jucãtori joaca pe trei ture şi fiecare au pus 32 de galbeni.Sa zicem ca primul jucator a câştigat doua puncte, iar al doilea unul. Acum trebuie sa joace ultima tura pentru un punct. Daca primul jucator ar câştiga ar lua toata miza adica 64 de galbeni, în timp ce daca al doilea ar câştiga fiecare ar avea doua puncte şi ar trebui împarţitã miza, adica 32 de galbeni la fiecare. Aşadar daca primul jucator ar câştiga 64 de galbeni i-ar apartine, dacã nu ar lua 32 de galbeni. Atunci dacã cei doi jucãtori doresc sã se opreasca aici primul ar zice: "Am asigurat un câştig de 32 de galbeni chiar daca pierd tura urmatoare, cât despre ceilalti 32 poate îi voi câştiga eu poate tu, şansele sunt egale. Haide sa împartim cei 32 de galbeni ramaşi egal iar eu voi lua şi pe cei 32 care îmi sunt asiguraţi." Primul jucãtor va avea 48 de galbeni iar al doilea 16.Mai departe sã zicem cã primul jucãtor a obtinut doua puncte iar al doilea nici unul şi sunt pe cale şa mai joace o tura pentru un punct. Daca primul jucator câştiga acest punct va câştiga şi jocul şi va lua 64 de galbeni, iar daca al doilea câştiga atunci jucatorii vor fi în situatia analizatã anterior. Dar, dacã nu mai doresc sã joace, primul jucãtor ar zice: "Dacã mai obtin un punct câştig 64 de galbeni, dacã pierd tot primesc 48 (ca înainte). Dã-mi 48 de galbeni pe care îi am sigur şi restul de 16 îi împartim în doua egal cum şansele sunt egale." Aşadar primul jucator ia 56 de galbeni iar al doilea 8.Şi în sfârşit primul jucator are un punct şi al doilea nici unul. Daca mai joaca pentru un punct şi primul jucator ar câştiga s-ar afla în situatia anterioara în care el are dreptul la 56 de galbeni, iar daca al doilea ar câştiga fiecare ar avea un punct şi câştigul ar fi împartit. Dar dacã nu ar mai dori sã continue primul ar zice: "Da-mi 32 de galbeni pe care îi iau sigur, şi împarte restul din 56 respectiv 24 (deoarece am deja 32) în douã." Atunci primul va avea 32+12=44 de galbeni şi în consecinţa, al doilea va avea 20 de galbeni.Pascal continuã rezolvând probleme asemanatoare când jocul este câştigat de cine obtine m+n puncte. Rãspunsul este dat de triunghiul sau aritmetic. Solutia problemei generalizate in care valoarea jucãtorilor este diferitã poate fi gãsitã în majoritatea cãrtilor de algebra şi este în concordanţa cu rãspunsul lui Pascal, deşi notaţiile pot fi diferite.Pascal a folosit aceastã nouã teorie în al nouãlea capitol al cãrtii sale Pensées. El spune urmãtoarele: Dacã valoarea fericirii eterne este infinitã chiar dacã probabilitatea ca o viaţa religioasa sa asigure fericirea eterna este mica, totuşi speranta perspectivã, mãsuratã prin produsul celor douã, trebuie sã fie destul de mare pentru a merita sa fi religios. Dacã se poate trage vreo concluzie din afirmatia aceasta este neclaritatea obţinuta când se aplicã formule matematice întrebarilor morale ale caror date nu sunt de obicei în sfera ştiintelor exacte, de aceea afirmaţia nu a fost apreciata pozitiv.Ultima lucrare matematicã a lui a fost Cicloida. in 1658. Cicloida este linia curbã trasatã de un punct de pe circumferinta unui cerc care se roteşte fara alunecare pe o dreapta. În 1630 Galileo a atras atentia asupra acestei forme de altfel graţioase, şi sugerase ca arcele podurilor sa fie construite astfel. Patru ani mai târziu Roberval a aflat aria determinatã de cicloidã. Descartes nu a apreciat aceastã solutie şi l-a provocat la aflarea tangentelor, aceeaşi provocare i-a fost trimisa lui Fermat care a rezolvat-o numaidecât. Câteva întrebari au fost puse de alti matematicieni. Acestea se refereau la curba şi la suprafata şi volumul determinate de cicloida la rotirea în jurul axei, bazei şi tangentei. Acestea la un loc cu aflarea pozitiei centrului de greutate al corpurilor solide formate au fost rezolvate de Pascal în 1658. Rezultatele au fost emise ca întrebari spre rezolvare. Wallis reuşeşte sa raspunda la toate cu exceptia celor legate de centrul de greutate. Soluţiile lui Pascal (afectate de metoda indivizibilitaţii) seamãnã cu rezolvarea pe care ar da-o un matematician din zilele noastre cu ajutorul calculului cu integrale. El a obţinut (prin însumare) echivalentul integralelor lui sin?, sin2? si ?•sin?, o limita fiind 0 sau 1?. De asemenea a investigat geometria spiralei lui Arhimede. Aceste studii, potrivit lui D'Alembert, formeaza o legatura între geometria lui Arhimede şi calcului infinitezimal a lui Newton.

Bibliografie: A short Account of the History of Mathematics de W. W. Rouse Ball a patra ediţie 1908 transcris de D.R. Wilkins School of Mathematics, Trinity College, Dublin

http://www.lovendal.net/wp52/blaise-pascal-autorul-operei-religioase-cugetari-a-fost-si-inventatorul-calculatorului/Blaise Pascal, autorul operei religioase “Cugetări”, a fost şi inventatorul calculatorului

Filozoful şi matematicianul francez Blaise Pascal (1623-1662) încă de mic copil, a dat semne că posedă însuşiri speciale şi o minte neobişnuit de ageră. Prin scurtele sale răspunsuri, cât şi prin întrebările pe care le punea asupra naturii lucrurilor, a dat reale speranţe tatălui său că va deveni un tânăr remarcabil. Tânărul Pascal a început să deprindă din arta realizării figurilor exacte la vârsta de 12 ani, descoperind că „suma unghiurilor unui triunghi este egală cu două unghiuri drepte“. Şi asta foarte simplu. În orele sale de recreere, fiind singur într-o sală, unde avea obiceiul de a se distra, lua o bucată de cărbune şi desena figuri pe ochiurile de geam, căutând mijloace de a face un cerc perfect rotund, un triunghi ale cărui laturi şi unghiuri să fie egale, şi alte lucruri asemănătoare. Căuta apoi proporţiile figurilor între ele.În decembrie 1639, familia Pascal a părăsit Parisul, pentru a locui la Rouen, unde tatăl său a fost numit colector de taxe pentru Normadia de Sus şi unde Blaise publică, în februarie 1640, „Eseul despre secţiunile conice“. După ce a lucrat 3 ani, între 1642 şi 1645, Pascal a inventat primul calculator mecanic, „Pascaline“ pentru a-l ajuta pe tatăl său în munca sa de colector de taxe. Această lucrare a fost socotită ca un lucru nou, căci prin ea s-a găsit mijlocul efectuării tuturor operaţiilor automat, cu o exactitate uimitoare, fără să fie nevoie de raţionament.În 1648, Pascal a observat că presiunea atmosferei scade cu înălţimea şi a dedus că vidul există deasupra atmosferei, iar în mai 1653, Pascal scrie „Tratatul despre echilibrul lichidelor“, în care explică legea presiunii.Revelaţia din 1654 În 1654, Blaise Pascal trăieşte o revelaţie religioasă care îi va schimba complet felul de-a fi, precum şi interesele cognitive. Acceptând şi asumând adevărul religiei creştine într-un mod profund personal, dar şi cât se poate de firesc, Pascal îşi marchează definitiv destinul. După această dată, Pascal face vizite la mănăstirea jansenistă Port-Royal des Champs, la 30 km sud-vest de Paris şi publică lucrări anonime reunite în Lettres provinciales, în 1656. Odată cu retragerea sa la Port-Royal, asumarea completă a trăirii creştine era săvârşită. Pascal îşi impune un mod de viaţă auster, retras.Începând cu acest moment, lumea îl va putea descoperi pe acel gânditor profund religios, care a elaborat proiectul unei Apologii a creştinismului, rămasă cu un titlu provizoriu, „Cugetări“.Nedesăvârşită, datorită unei morţi premature, această lucrare a rămas într-o formă fragmentară. Găsite după moartea lui Pascal, manuscrisele sunt expresii ale gândurilor sale consemnate pe bucăţi de hârtie, de diferite dimensiuni, pe măsură ce-i veneau în minte. Cu pana sau cu creionul, îşi nota ideile, cugetările, care erau rodul unor îndelungate meditaţii sau frânturi de gând spontane. Demnă de remarcat este intenţia iniţială a lui Pascal în privinţa metodei sale de a scrie.„Voi scrie aici gândurile mele fără ordine, dar poate nu într-o confuzie lipsită de scop. Aceasta este veritabila ordine care-mi va marca obiectul chiar prin dezordine. I-aş acorda prea mare onoare subiectului meu, dacă l-aş trata în ordine, pentru că vreau să arăt că el este incapabil de ordine.“ („Cugetări“).Pascal respinge sistemele exclusiv raţionale, cu atât mai mult cu cât cugetările sale se îndreaptă spre analiza fiinţei umane şi a lui Dumnezeu la un nivel existenţial, ce depăşeşte posibilităţile de reprezentare ale intelectului.Moare la 39 de ani, pe 19 august 1662, în urma extinderii tumorii maligne din stomac, şi este înmormântat în Cimitirul „St. Étienne-du-Mont“, în Paris.Pariul lui PascalSe presupune, asemenea cazului unui pariu, că există două variante, existenţa lui Dumnezeu şi a vieţii de apoi sau non-existenţa acestora. Putem alege una dintre aceste variante. Dacă prima variantă este adevărată şi Dumnezeu există, cei care au mizat pe ea au numai de câştigat. Ceilalţi, în schimb, au pierdut totul, pentru că îşi vor primi pedeapsa pentru necredinţa lor. Pe de altă parte, dacă a doua variantă este cea adevărata, iar Dumnezeu şi viaţa de apoi sunt doar nişte himere, cei care au pariat pe existenţa lor nu au câştigat nimic, dar nici nu au pierdut nimic.

http://plato.stanford.edu/entries/pascal/

Blaise PascalFirst published Tue Aug 21, 2007Pascal did not publish any philosophical works during his relatively brief lifetime. His status in French literature today is based primarily on the posthumous publication of a notebook in which he drafted or recorded ideas for a defence of Christianity, the Pensées de M. Pascal sur la religion et sur quelques autres sujets (1670). His philosophical commitments can be gleaned from the contributions he made to scientific and theological debates in France in the mid-seventeenth century.

1. Life and Works

2. Nature and Grace 3. Free Will 4. Theory of Knowledge 5. Ethics and Politics 6. Pascal and Human Existence Bibliography

o Pascal's Works o Related Early Works o Recommended Secondary Literature

Related Entries

1. Life and WorksPascal was born in Montferrand, France, on 19 June 1623, and died thirty-nine years later in Paris (19 August 1662). Following his mother's death when he was three years old, Blaise was reared by his father, Étienne, in the company of his two sisters, Gilberte (b. 1620) and Jacqueline (b. 1625). Later, in Paris, the family hired a maid named Louise Delfault, who became effectively a member of the close-knit family. Pascal's father was an accomplished mathematician, and he provided the only formal education to which his son was exposed. As Carraud (1992: Chapter 2) shows, this arrangement was unique in the seventeenth century for a young man of Pascal's social status. He was never trained in theology or the philosophy of the schools, and his exclusively domestic education focused on classical languages and mathematics. The decision to educate Pascal at home was consistent with the fact that he suffered from very poor health for most of his life, beginning at the age of two. Although his sister, Gilberte, may have exaggerated in her hagiographical La vie de M. Pascal, she reported Pascal as claiming that ‘from the age of eighteen, he never passed a day without pain’ (I, 67: all references to Pascal are to Pascal, 1998/2000, with volume and page number). He continued to be so ill that, at the age of twenty-four, he could tolerate no food other than in liquid form, warmed, and fed to him drop by drop by his sisters or his nurse (Vie: I, 69). Gilberte's biography also confirms that, as his sisters matured, they assumed many of the nursing responsibilities for their infirm brother that would otherwise have been assigned to his mother.The Pascal family moved residence frequently, for political and financial reasons. They transferred initially to Paris in November 1631, although Étienne was forced to return seven years later to his original home in what had since become Clermont-Ferrand, because he expressed public dissent concerning the crown's fiscal policies. Meantime, France had declared war on Spain in 1635, and this intermittent campaign lasted for most of Blaise Pascal's life. The external and internal political context in which he lived, together with very public disputes between competing religious and theological traditions in which he participated, helped determine the issues to which Pascal contributed philosophical comments in the 1640s and 1650s. Following the revolt of the Nu-Pieds in Normandy, in July 1639, Pascal's father was awarded a new post as a tax collector in Rouen, to which he moved in 1639 (and was followed, in 1640, by Blaise). Meanwhile, Blaise continued his education at home. While still in Paris, he had written the short Essai pour les coniques (1640) and, despite his youth, was introduced to the Mersenne circle by his father as a promising young mathematician. At Rouen he developed the first prototype of his calculating machine (1645), and began to experiment with mercury barometers. Pascal's introduction to barometric experiments occurred by chance when the royal engineer, Pierre Petit (1598–1667), passed through Rouen in September 1646 and informed both Pascals, father and son, about Torricelli's experiments in Italy. Blaise Pascal performed experiments with mercury barometers initially in Rouen and Paris, and published Expériences nouvelles touchant la vide in 1647. He subsequently arranged for his brother-in-law, Florin Périer, to conduct on his behalf one of the most famous experiments of the scientific revolution on the puy-de-Dôme, in the Auvergne.Périer arranged for two identical barometric tubes to be filled with mercury, on 19 September 1648. He left one at the bottom of the mountain, and charged a local friar to keep watch during the day and note any changes in the height of the mercury. Together with other witnesses, Périer climbed the mountain and took readings of the height of the mercury on the mountain top, and subsequently at two intermediate places on their return journey down the mountainside. As expected, the height of the mercury varied inversely with the height (above sea-level) at which the measurements were taken. When the experimenters rejoined the friar at the bottom of the mountain and compared the measurements on both tubes, they concurred exactly. The friar reported that, throughout the day, there had been no variation in the height of the mercury column that he observed, ‘despite the fact that the weather was very changeable, sometimes calm, sometimes rainy, sometimes very foggy and sometimes very windy’ (I, 433). The results of this experiment were published as Récit de la grande expérience de l'équilibre des liqueurs (1648). Pascal argued, mistakenly, that the experiment guaranteed his interpretation of its results [see below, Section 4].Pascal's initial encounter with Jansenism occurred when his father slipped on ice and dislocated or broke his thigh, in January 1646. Following this accident, the Deschamps brothers, who had bone-setting and nursing

skills, came to live in the Pascal household at Rouen for three months. They introduced the family to the strict observance of Christianity inspired by the work of the Dutch theologian, Cornelius Jansen (1585–1638), and the French theologian, Jean Duvergier de Hauranne, who is usually known as the Abbé de Saint-Cyran (1581–1643). Their evangelical work relied partly on Jansen's short treatise, the Discours sur la réformation le l'homme intérieur, which was based on the text of I John 2:16: ‘For all that is in the world is the concupiscence of the flesh and the concupiscence of the eyes and the pride of life, which is not of the Father but is of this world.’ Jansen taught that a desire for knowledge was one form of concupiscence and he argued that, from this ‘illness … arises the investigation of nature's secrets (which are irrelevant to us), knowledge of which is useless, and which men do not wish to know except for the sake of knowing them’ (Jansen 2004: 24). Jansen recommended that Christians should instead turn aside from the pride and concupiscence of human knowledge and scientific investigations, and should focus exclusively on knowledge of God. While this encounter with Jansenist theology is sometimes described as Pascal's first conversion, it is unlikely that, in 1646, Pascal made the definitive choice about the insignificance of mathematical and scientific work that characterised his change of heart in the 1650s. He returned to Paris with his sister, Jacqueline, in 1647. Descartes met him there, in September 1647, during an extended trip to Paris from his usual residence in the north of Holland, and discussed with Pascal some of the implications of the Torricelli experiments.The Pascals (Étienne, Blaise, and Jacqueline) left Paris again during the civil war known as the Fronde (1648), but returned later that year to another address in the French capital. The settlement agreed by Mazarin and the regent with the parlement to end the Fronde meant that Étienne had become redundant as a tax-collector in Rouen. This return to Paris was the beginning of a radical change in the family security that Blaise Pascal had enjoyed since his earliest years. His older sister Gilberte had married Florin Périer in June 1641 and had moved to Clermont-Ferrand. However, his younger sister, Jacqueline, expressed a desire, in May 1648, to become a nun and enter the Port-Royal convent in Paris, which was under the spiritual supervision of Jansenists and where one of Arnauld's sisters was a prominent Abbess. Étienne's opposition caused Jacqueline to defer implementing her decision as long as he was still alive. However, four months after her father's death in 1651, and despite her brother's opposition, Jacqueline Pascal joined Port-Royal. At this point, for the first time in his life, Blaise Pascal was alone and in poor health. He soon began to accept spiritual guidance from his sister Jacqueline and subsequently from a prominent Jansenist, Antoine Singlin (1607–64).In the summer of 1654, Pascal returned briefly to mathematics in correspondence with Pierre Fermat (1601–65) about calculating the probabilities involved in gambling. He summarized his findings in the Traité du triangle arithmétique which, like much of his other work, remained unpublished until after his death. In fact, as Edwards explains (Hammond, 2003: Chapter 3), Pascal's contribution to probability theory was not recognised until it was used by Bernoulli in the early eighteenth century.During the night of 23 November 1654, Pascal had a dreamlike or ecstatic experience which he interpreted immediately as a religious conversion. He wrote a summary of the experience in a brief document entitled the Memorial, which he sewed into his coat and carried with him until his death. The intensity of this experience resulted in a definitive change in Pascal's lifestyle, in his intellectual interests, and his personal ambitions. After 1654, he terminated the discussions of probability with Fermat, and he cancelled plans to publish a booklet on the vacuum that was ready to go into print. This booklet appeared posthumously as Traités de l'équilibre des liqueurs et de la pesanteur de la masse de l'air (1663). Pascal's brother-in-law, Florin Périer, explains in his introduction that, for ten years before his death, Pascal was aware of ‘the vanity and nothingness of these types of knowledge, and had expressed such disgust for them that he could hardly tolerate intelligent people spending their time and speaking seriously about them’ (I, 459). Pascal had entered the final period of his life, which was dominated by religious controversy, continual illness, and loneliness. This was also the period in which he assumed the challenge of defending Arnauld and, more generally, Jansenist theology in the Provincial Letters.Antoine Arnauld (1612–94) was a prominent theologian in the Sorbonne, most famous for his defence of Jansenism in De la fréquente communion (1643). Following the condemnation by Pope Innocent X (May 1653) of five propositions about grace that were allegedly found in Jansen's posthumously published book, Augustinus (1640), Arnauld was threatened with censure by the Theology Faculty at the Sorbonne. This provoked Pascal into writing a series of open letters, between January 1656 and March 1657, which were published one by one under a pseudonym and became known as the Provincial Letters. They purported to inform someone living outside Paris (in the provinces) about the events that were newsworthy in theological debates at the Sorbonne and, more widely, in the Catholic Church in France. The Letters rely on satire and ridicule as much as on logic or argument to persuade readers of the justice of Arnauld's cause and of the unsustainability of his critics' objections. However, despite Pascal's efforts, Arnauld was expelled from the Sorbonne (February 1656). Those who lived at Port-Royal des Champs — another convent associated with Port-Royal, which was outside the city boundaries — agreed to leave voluntarily (March 1656) under threat of forcible expulsion, and the convent was eventually razed to the ground. The Provincial Letters are Pascal's deeply personal, angry response to the use of political power and church censure to address what he considered to be a matter of fact, and to what he perceived as the undue influence of a lax Jesuit morality on those who held political and ecclesiastical power in

France. The Jesuits were not members of the Sorbonne and were not officially involved in Arnauld's censure; it is not immediately clear, therefore, why Pascal, in the course of writing the letters, devoted so much energy to criticizing the Jesuits. He may have blamed Arnauld's fate on the Jesuits' influence in Rome and their political connections with the monarchy in France.The final years of Pascal's life were devoted to religious controversy, insofar as his increasingly poor health permitted. During this period, he began to collect and draft ideas for a book in defence of the Catholic faith. While his health and premature death partly explain his failure to complete this work, one might also suspect that an inherent contradiction in the project would have made the task impossible. Apologetic treatises in support of Christianity traditionally required the author to provide reasons for religious faith; however, according to Pascal's radical theological position, it was impossible in principle to acquire or support genuine religious faith by reason, because genuine religious faith was a pure gift from God. Having collected ideas for some time, Pascal began the task of cutting and pasting his draft notes into a coherent form before he died; however, he left the manuscript in such a condition that subsequent editors failed to agree on any numbering system or on the order, if any, in which they should be read. The most frequently quoted modern editions of the Pensées—those of Lafuma, Sellier, or Le Guern—provide concordances to the numbering systems adopted by alternative editions. Because the Pensées are a posthumously published notebook, it also remains unclear whether Pascal endorsed the opinions that are recorded in these notes, or whether he planned to save some of them merely for comment or critique. They are reliably used only when Pascal expressed similar views elsewhere. One of the most famous and most extensive notes in the Pensées (Fragment 397: II, 676–81) is the so-called ‘wager’ in favour of belief in God.Cole (1995, Chapter 15) argues that Pascal exhibited signs of manic depression and an almost infantile dependence on his family in his mature years. In addition, many of the reported details of his personal life suggest a kind of fundamentalism about religious belief that is difficult to reconcile with what is taken today as the critical stance that defines philosophy as a discipline. For example, if his sister's Life is accurate, Pascal seems to have had an almost obsessive repugnance for any expressions of emotional attachment, which Gilberte attributed to his high regard for the virtue of modesty. She reports that ‘he could not even tolerate the caresses that I received from my own children’ (I, 83). Pascal believed that God performs miracles, among which he included the occasion when his niece was cured of a serious eye condition by what was believed to be a thorn from the passion of Christ. Pascal's commitment to Jansenism was unqualified, although he denied in the Provincial Letters that he was ever a member of Port-Royal (I, 781). Everything we know about Pascal during his maturity point to a single-minded, unwavering belief in the exclusive truth of a radical theological position that left almost no room for toleration of alternative religious perspectives. This is not to suggest that it is impossible to be a religious believer and a philosopher; there are too many obvious counterexamples to such a suggestion. However, the intensity of Pascal's religious faith, following his conversion, seems to have made philosophical inquiries irrelevant to him, with the result that he approached questions during the final ten years of his life almost exclusively from the perspective of his religious faith. It was this perspective that predominated in the Pensées.There is a complementary reason for urging caution about reading Pascal as a philosopher. He wrote much but published little, none of it philosophy in the sense in which that term is used today. Apart from his brief essays on the vacuum and the Provincial Letters, all his writings were edited and amended posthumously by collaborators who were still involved in the theological controversies that had dominated Pascal's later life. For example, he seems to have contributed to an early version of the Port-Royal Logic (Arnauld and Nicole, 1993) that was subsequently published in 1662; and the Entretien avec M. de Sacy was composed many years after his death, based on the recollections of an editor. Thus philosophical opinions that were attributed to him in various draft writings should be read with caution, and should be understood with reference to the context in which they were published by others apart from the author. His apparent disenchantment with philosophical studies is reflected in Fragment 77 of the Pensées: ‘we do not believe the whole of philosophy to be worth one hour's effort’ (II, 566). This may also testify to the extreme ill-health and loneliness he experienced in his final years, when he reported that he could find consolation for his misery only in religion.Pascal was never employed in any capacity, and lived modestly from the financial support provided by his family. He died in the care of his sister, Gilberte, and was buried in the church of Saint Étienne du Mont, in Paris. His younger sister, Jacqueline, had predeceased him at the Port-Royal convent in October 1661.2. Nature and GracePascal's philosophical reflections are dominated by a theological interpretation of the human condition, following Adam's Fall from grace, that he claimed to have borrowed from Saint Augustine. On this view, human nature is essentially corrupt, and there is no possibility of recovery by natural means or human effort. This theological perspective determined Pascal's views about human freedom, and about ethics and politics; it also set extra-philosophical limits to his theory of knowledge, and prompted the negative assessment adopted during the final years of his life about the relative worthlessness of scientific or mathematical research.

Following Augustine, Pascal emphasized the extent to which any recovery from the fallen state of human nature was a gift from God, one that was not earned or deserved in any way by human agents. This divine gift included, as one of its elements, religious faith itself, the capacity of humans to believe the theological interpretation on which the implied worldview depended. Other commentators on Christian belief in the seventeenth century, such as John Locke or John Toland, presupposed that what a Christian is invited to believe must be intelligible, so that faith merely compensated for a lack of evidence in support of a particular proposition and made it possible for a Christian to accept it as true. For these philosophers of religion, there were no mysteries in Christianity if that term included propositions that we cannot understand. For Pascal, however, faith provides appropriately disposed Christians with a means to transcend the limits of what is intelligible and to accept as true even matters that we cannot understand. To claim otherwise would be to set limits to the reality of God and to reduce religious faith to the compass of human understanding. The Pensées suggest: ‘if one submits everything to reason, our religion will contain nothing that is mysterious or supernatural’ (Fragment 162: II, 602). Thus those who are given the gift of genuine religious faith are expected not only to accept things that are uncertain but, especially, to accede to realities that are incomprehensible. Pascal offered no explanation of how this was possible.This degree of incomprehensibility in the content of religious belief would have been consistent with a corresponding relativism about the competing claims of different religious traditions. For example, each tradition might have been presented as an alternative perspective on the transcendent. However, Pascal was as committed to the exclusive truth of Catholicism, and even to his preferred interpretation of that tradition, as he was open to belief in mysteries. ‘I see several inconsistent religions, all of which except one are false. Each one wishes to be believed on the basis of its own authority and threatens unbelievers. I therefore do not believe them for that reason.’ (Fragment 184: II, 608). For Pascal, the Roman Catholic Church was the only true church, ‘outside of which I am fully convinced there is no salvation’ (Provincial Letters: I, 781).In contrast therefore with many of his contemporaries in France, such as Descartes or Malebranche, Pascal also rejected the suggestion that one could prove the existence of God by rational means. ‘The metaphysical proofs … have little value’ (Fragment 179: II, 605). A fortiori, it was not necessary, as Malebranche had argued, that one prove God's existence by rational arguments as a precondition for believing that God revealed various truths in the Scriptures. According to that way of thinking, we have no basis for believing the alleged content of revelation unless we have prior proof that there exists a God who is capable of communicating with us. For Pascal, however, reason was completely inadequate to the task of connecting with a transcendent divinity, and the only way to God was by ‘faith’.Thus the discussion of wagering in favour of religious belief in the Pensées (Fragment 397: II, 676–81), which Pascal drafted and revised a number of times, was written from the perspective of someone who already believes in God, and who assumes that their belief is itself a gift from God. Pascal had independently studied the mathematics of gambling, and while considering how to compose an apology or defence of Christianity, he reviewed ways in which a committed Christian might adapt the logic of wagering to show that their belief is not unreasonable. However, according to Pascal's deepest theological convictions, nothing that he wrote in this context could persuade an unbeliever to become a believer in any sense that could lead to salvation. No one can communicate religious faith in Pascal's sense to others by reasoning or wagering, nor can such faith be self-induced by the same methods. For Pascal, a decision to believe God's revelation (in the relevant sense of ‘believe’) is not based on rational calculation nor, as indicated above, does it presuppose a philosophical argument in favour of God's existence. A calculation of the probability of one's wager is logically posterior to belief, and it purports to show only that those who have accepted divine grace and believed in God have made a wager that is not unreasonable.The various kinds of divine assistance (or, in the language of theology, grace) by which human beings could overcome their Fallen condition was the subject of intense theological controversy in the seventeenth century. The Church had condemned as heretical the Pelagian theory that human beings could achieve eternal salvation by the use of their unaided, natural powers. Various opinions to the effect that they could make some independent contribution to this process were equally condemned as semi-Pelagian. Both suggestions were thought to deny the significance of the Incarnation. Jansenism represented a starkly exclusive interpretation of how God's assistance enabled Fallen human beings to recover from the effect of Original Sin by the influence of ‘efficacious grace’. However, such a unilateral interpretation of God's intervention seemed to make human effort redundant. Pascal mocked the theory that God assisted weak human beings by means of a ‘sufficient grace’ which was not sufficient, and that this insufficient grace required an independent contribution from human agents. ‘By sufficient grace you mean a grace that is not sufficient’ (Provincial Letters: I, 601). In response to what he understood as various degrees of Pelagianism, Pascal attempted to formulate a position according to which no human effort could contribute to salvation, even as a partial cause, and at the same time to acknowledge the efficacy of God's agency if He chooses freely to assist undeserving sinners.This controversy about the relative efficacy of God's grace was most evident in the discussion of free will, and in Pascal's account of how we come to know the truth about radically different kinds of reality, the natural and the supernatural.

3. Free WillHow to reconcile the complementary agency of God and of natural causes was a central metaphysical problem for those, in the seventeenth century, who accepted divine intervention in the natural world. One of the solutions offered (for example, by Malebranche and La Forge) was occasionalism, and it was motivated in part by the recognition of God's omnipotence. Unless God's causality were to be understood as inadequately efficacious, occasionalists thought it was redundant to require a supplementary causal activity on the part of natural phenomena or human agents in order to cause the effects that are attributed to them in ordinary language. Pascal's account of free will reflected this dilemma at the heart of human choice. His discussion owes much to that of Augustine in On Free Choice.Pascal was little concerned about the freedom of human choices that result, for example, in deciding to read one book rather than another, or in analyses of what it means to claim that an agent could have done or chosen otherwise. The comprehensive concupiscence under which human nature struggled, according to Pascal's account of the Fall, implied that human ‘choices’ are determined by the dominant desires of each individual. That provided a naturalistic theory of mundane human choices. The less mundane cases, which were the focus of Pascal's interest, includes those where someone ‘chooses’ to act morally or otherwise. The Jansenist theory of grace was that God intervenes in the lives of individuals and makes it possible for them to choose something that otherwise they could not choose, namely, to act in a manner that is conducive to salvation. If God's assistance were sufficient to guarantee its efficacy, it would seem as if the choice of a human agent were determined by God's greater power. On the other hand, if God's grace were inefficacious, it would seem as if He provided inadequate assistance by relying on natural human powers to exercise free will and thereby to supply what was missing from divine grace. This latter position was rejected by Pascal as heretical and semi-Pelagian.Pascal's solution was to repeat his interpretation of Augustine's theory of grace, and to re-describe as ‘free’ the choice of a human will that is ‘infallibly’ motivated by God's efficacious grace. ‘Human beings, by their own nature, always have the power to sin and to resist grace, and since the time of their corruption they always have an unfortunate depth of concupiscence which infinitely increases this power of resistance. Nevertheless, when it pleases God to touch them with his mercy, He makes them do what he wants them to do and in the manner in which he wishes them to act, without the infallibility of God's operation destroying in any way the natural freedom of human beings … That is how God disposes the free will of human beings without imposing any necessity on them, and how free will, which can always resist grace but does not always wish to do so, is carried both freely and infallibly towards God’ (Provincial Letters: I, 800, 801). The Écrits sur la grâce, which was drafted at about the same time as the Provincial Letters, summarizes the Augustinian position as follows: God predestines some human beings for salvation and saves them by ‘means that are certain and infallible’ (II, 262). There are also others to whom God gave graces ‘that would have led them to salvation had they used them properly’ (I, 262), but He chose not to provide them with the ‘unique grace of perseverance’ without which it is impossible to be saved. By defending the necessity of God's grace and its infallible efficacy, and by assuming that some people resist this divine assistance, Pascal was forced by the logic of his position to endorse predestination. If God were to provide efficacious grace to each person, they could not fail to be saved. Therefore, if some are damned, it must be because God has decided not to rescue them from the Fallen condition into which they have been born as a result of Adam's sin.It would be easy, philosophically, to accept the limitations of human powers on which this account is based as a theologically inspired account of weakness of the will. However, it is difficult to see in what sense human choice is free when it is motivated infallibly by a divinely originated desire that the will of each individual, to whom it is granted, finds irresistible. For Pascal, one's choice of salvation is free in the sense that it expresses one's strongest desire; but the desire itself is communicated only to those who are predestined by God, and is such that the recipient is guaranteed to follow it.4. Theory of KnowledgePascal did not set out a coherent theory of knowledge or philosophy of science in any single text. His essays on the vacuum (written during the late 1640s), De l'esprit géométrique (1655), and the Entretien avec M. de Sacy (published posthumously), provide indications of conflicting intuitions about natural knowledge, although they all accept the special role of religious belief. The Provincial Letters provide a statement of his general overview: ‘How do we learn the truth about facts? That will be from our eyes … which are the appropriate judges of fact, as reason is of natural and intelligible things, and the faith is of things that are supernatural and revealed’ (I, 810–11). Apart from faith, which is directed to revealed truths and the supernatural world, Pascal focuses on ‘experience and reason’ (I, 455) as the only ways of acquiring knowledge of the natural world.The scientific and theological controversies in which Pascal became involved engaged him in epistemological questions that were both commonplace and unresolved in the seventeenth century. These included queries about observations or experiments as sources of evidence, the certainty or otherwise of various types of knowledge claim, and the status of hypotheses that are constructed to explain natural phenomena.Pascal was sympathetic to the mild, comprehensive pyrrhonism that is found in Montaigne: ‘Montaigne is incomparable … for disabusing those who cling to their opinions and who believe that they have found

unshakeable truths in the sciences’ (Entretien: II, 97). Despite this tendency towards scepticism, Pascal frequently expressed confidence in the certainty with which we can know ‘matters of fact.’ For example he argued, in the Provincial Letters, that ‘matters of fact are proved only by the senses’ and that they are ‘easily decided’ (I, 812, 723). This was consistent with one of the main lines of argument in the Letters. Pascal's defence of Arnauld hinged on the claim that the five propositions condemned by the Pope as heretical did not occur in the text of Augustinus, and that this fact could be established by inspection, i.e. by reading the book. On questions of fact, therefore, even the Pope could be mistaken, and it is inappropriate to appeal to any authority apart from one's senses to decide a factual question: ‘authority is useless in that context’ (Preface to the Traité du vide: I, 452). The same kind of certainty about experimental facts, he thought, should have resolved the dispute about heliocentrisim that led to Galileo's house arrest. ‘It was in vain’ therefore that the Jesuits ‘obtained from Rome a decree against Galileo … That is not what will prove that the earth does not move; and if one had consistent observations that proved that the earth revolves, all the men in the world could not stop it moving’ (Provincial Letters: I, 813).Even if facts could be known with certainty by observation, Pascal conceded that it would require the use of reason to understand or explain natural phenomena, and that ‘the secrets of nature are hidden’ (Preface to the Traité du vide: I, 455). To penetrate those secrets, one had to have recourse to hypotheses. Pascal's account of how hypotheses are confirmed, and the degree of certainty that one could claim for them, were ambivalent. When reflecting on the results of the puy-de-Dôme experiment, he argued against critics that not only had he established that the mercury rises in a barometer because of the weight of the air, but that the empty space at the top of a barometric tube is a vacuum. Others (including Descartes) accepted the experimental results, but disputed this interpretation of them. They accepted that mercury is supported in a barometer by the weight of the air; they also argued, however, that the apparently empty space in a barometric tube contains a subtle matter of some kind, that it has physical properties (for example, a specific size, or the capacity to be penetrated by light, etc.), and that both interpretations of the nature of this apparent vacuum are consistent with the experimental results.In this context, Pascal argued as follows. There are three types of hypothesis. The negation of some hypotheses implies an absurd consequence, and they must therefore be true. The affirmation of others implies an absurdity, and these must be false. In a third category, if no absurd conclusion results from either the affirmation or negation of an hypothesis, no conclusion may be drawn about its truth. This classification of possible outcomes assumed that the logic of scientific theories could be modelled on mathematical proofs. At least in the third case, Pascal seems to have recognized that, logically, different assumptions may ‘lead to the same conclusions, for everyone knows that truth is often concluded from falsehood’ (Entretien: I, 90). When applied to experimental situations, it meant that one could get apparently confirming results from a poorly executed experiment or one that is designed according to mistaken hypotheses. Accordingly, even the phenomenal success of the puy-de-Dôme experiment did not show conclusively that Pascal was correct about the vacuum. On the other hand, Pascal implicitly assumed that a negative experimental result disconfirmed the hypothesis that an experiment was designed to test, by analogy with the claim that ‘absurd’ consequences could be attributed to affirming or denying individual hypotheses rather than clusters of interconnected hypotheses. The Duhem-Quine thesis, as it is known today, shows that negative experimental results may be attributed to any of the many hypotheses that are assumed in observations or experiments, and that the certainty to which Pascal aspired cannot be realized even when experimental results are inconsistent with expectations.This analysis left unresolved the status of scientific hypotheses. Do hypotheses provide genuine knowledge, despite their uncertainty? Or did Pascal anticipate the solution later adopted by Locke and restrict genuine knowledge to two categories: (a) what is perceived, and (b) what is ‘demonstrated’? De l'esprit géométrique adopts a foundationalist perspective on knowledge, in which ‘principles’ are first established and the certainty of other knowledge-claims derives from that of the principles. Such logically interconnected principles and conclusions were called ‘demonstrations’. Thus every demonstration requires that one first identify ‘the evident principles that it requires. For, if one does not guarantee the foundations, one cannot guarantee the building’ (II, 175). One establishes the certainty of propositions if they are ‘deducible by infallible and necessary logical steps from such axioms or principles, on the certitude of which depends all the certitude of the consequences that are properly deduced from them’ (letter to Father Noël: I, 378). This invites the question: does physical science provide demonstrations in this sense? Pascal limited ‘demonstration’ to mathematics and ‘whatever imitates it’ (II, 180). At the same time, he seems to have believed that his own physical investigations were sufficiently similar to mathematics that they amounted to demonstrated knowledge, and that experiments or observations provided their foundational principles.Accordingly, Pascal's preface for the Traité du vide (1651) claims: ‘the experiments that provide us with an understanding of nature consistently proliferate; and, since they are the only principles of physics, their consequences proliferate accordingly’ (I, 455). The certainty of experimental results based on observation, their role as principles of a scientific demonstration, and the facility with which natural philosophers could perform appropriate experiments or make relevant observations, led Pascal to an optimistic interpretation of scientific

progress. He claimed that, when researchers work together, they ‘make continual progress in science in proportion as the world gets older’ (I, 456). This apparently bright future for physical sciences was contrasted with the scientific failure of earlier natural philosophers, ‘those timid people who did not dare to discover anything in physics’ (Preface to the Traité du vide: I, 454) and is reflected in the comment in the Pensées, Fragment 654: ‘To what extent have telescopes revealed realities to us that did not exist for our philosophers of old?’ (II, 807).In summary, Pascal adopted an interpretation of natural science which exaggerated both the ease with which the interpretation of observations and experiments could be agreed, and the simplicity of the logical links between theories and their apparently confirming evidence.In contrast with all knowledge that is derived from experience and reason, Pascal identifies ‘authority’ as the exclusive foundation of religious belief. Authority depends on memory and is purely historical, because the objective is simply to find out what someone said or wrote. This applies ‘especially in theology’ (Preface to the Traité du vide: I, 452), a discipline which Pascal presents as if there could be no dispute about what is revealed in the scriptures or, more fundamentally, about whether a particular writing belongs among the canonical texts. He had to recognize that there were many religious traditions that claimed to report divine revelations, and that each in turn rested its claims on its own authority as a reliable witness to earlier historical events and their interpretation. Even within Catholicism, Pascal was familiar with the decisions of at least some church Councils that determined which interpretations of its doctrinal history were acceptable and which were anathemized as heretical. Since he rejected the validity of rational arguments as a criterion for distinguishing between what was authentic or otherwise in Christian belief, he had to rely ultimately on a personal choice of what to believe about the supernatural, and then to interpret that personal choice as if it were inspired by a special grace from God.It seems evident that the circularity of Pascal's self-justification could be repeated, with appropriate changes, by equally committed members of other religious traditions.5. Ethics and PoliticsIn the discussion of what he described as the ‘perniciously lax’ morality of the Jesuits, in the Provincial Letters, Pascal classifies many human actions — such as homicide, when self-defence is not relevant — as obviously immoral, and as widely recognised as such. He characterizes these immoral actions variously as contrary to the ‘natural light’, to ‘common sense’ or the ‘natural law.’ As Ferreyrolles (1984) shows, there are numerous references in Pascal to a ‘law of nature’. However, Pascal does not argue that this natural law can be discovered by reason, or that it acquires its obligatory force from human convention or contracts. The Jansenist interpretation of the human condition implied that human nature is corrupt, and therefore that reason is now an unreliable moral guide. ‘There are undoubtedly natural laws, but our fine reason was corrupted and it has corrupted everything’ (Fragment 56: II, 560). According to this view, God had provided reliable moral guidance to human beings in the prelapsarian state of nature, and some remnants of God's law continue to be reflected in Fallen nature. Natural law, therefore, is what remains of God's law in our current state of concupiscence. There is thus no independent, philosophical account of morality available in Pascal, apart from the law of God which is more or less dimly revealed.According to God's law, or those elements of it which survive in the widely held opinions of human beings all over the world, there are certain actions which are intrinsically evil or good. Our moral duties include not only the more familiar examples, such as the obligation to refrain from voluntary homicide; Pascal also quotes with approval from Cajetan that ‘we are obliged by justice to give alms from our surplus, to alleviate even the common necessities of the poor … those who are rich are merely stewards of their surplus, in order to give it to whoever they select from among those who are in need’ (Letters: I, 714).Having assumed that there are objective moral obligations, Pascal directs his critique, both in the Provincial Letters and in his contributions to the Écrits des Curés de Paris, to the claim, attributed to Jesuit casuists, that one can change radically the moral character of many actions by changing one's intention at the time of their performance. On this account, if an agent acts immorally while formally intending to act immorally, nothing can excuse the action in question. In all other cases, however, it is possible to modify the moral character of the action by applying the method of ‘directing the intention, which consists in selecting something that is permitted as the objective of one's actions’ (Letters: I, 649). This escape from moral responsibility relies on the principle that ‘it is the intention which determines the moral quality of an action’ (Letters: I, 679).The claim that one could direct one's intention away from what is otherwise a morally reprehensible action was consistent with the casuists' defence of the doctrine of ‘probabilism’. This doctrine, to which Pascal also objected, meant that one may decide moral issues according to any opinion which is said to be ‘probable’, even if it is much less probable that alternative opinions. ‘Probable’ in this context was defined as ‘everything that is approved by well-known authors’ (Letters: I, 732). The limits of what was morally acceptable were thus provided by examining the writings of approved authors and finding the least demanding moral opinion available in the literature. Pascal's satirical critique of Jesuit casuistry assumes, in contrast, that human actions have a moral character that is independent of the private thoughts or intentions of the agent who performs them, and that one cannot ameliorate them by ‘intending’ results that differ from the actual effects or consequences that follow

naturally from a given action. In that sense, Pascal's critique is an early version of a modern objection to the so-called ‘Principle of Double Effect.’Pascal's political theory was likewise dictated by his account of human concupiscence. According to Fragment 90 of the Pensées, ‘concupiscence and force are the sources of all our actions. Concupiscence causes voluntary actions, and force causes those that are involuntary’ (II, 570). Although there was a state of nature before the Fall of Adam, human relations are now completely compromised by concupiscence and by the exercise of power by one person over another. One inevitable effect of this unwelcome subservience is that we are coerced into obeying those who exercise political power over us, and this can be interpreted as punishment for our sinful condition. The Trois Discours sur la condition des grands distinguishes between natural gifts or abilities, which vary from one individual to another and may deserve our esteem, and variations in social status or political power which result from human contingency and require only that we obey and salute those who happen to be our superiors (II, 194–9). The natural equality of human beings that is implicit in this analysis, however, provides no basis for a theory of justice which would legitimate opposition to an established civil society or government, no matter how tyrannical it may be. In fact, there is no independent perspective in Pascal's writings from which one may query whether the laws of a country are just; they are just, by definition, because they are the laws. ‘Justice is what is established; all laws are just because they are established’ (Fragment 530: II, 776). A more extreme expression of the same view, in the Pensées, is that ‘justice, like finery, is dictated by fashion’ (Fragment 57; II, 562).This political conservatism is reflected in Pascal's view that ‘the worst evil of all is civil war’ (I, 569). In the Provincial Letters, he directs readers to the moral teaching of the Gospels to guide them in political action. ‘The Church … has always taught her children not to render evil for evil; … to obey magistrates and superiors, even those who are unjust, because we must always respect in them the power of God who has set them over us’ (I, 744). This compulsory tolerance of the status quo, for the sake of the common good, did not preclude comparative assessments of the merits or otherwise of different political systems. However, even in such assessments, the criterion of judgment remained the extent to which various states facilitated citizens in the performance of their primary duties to God.The appropriate attitude of subjects or citizens to the political powers that govern them was exemplified, acutely, in the demand by the civil authorities in Paris that even conscientiously objecting Jansenists had to sign and obey the formulary which condemned the five propositions allegedly found in Jansen's work. Dissenters like Pascal were not required to assent, in conscience, to what they did not believe; but they were required to assent in their behaviour and obey their political and ecclesiastical superiors. Likewise, the subjects of Pascal's polity were not required to esteem their political masters, nor to hold beliefs about them as human beings which they believed were false. It was enough that they obey them, that they observe the laws in their behaviour, and offer them the public deference that was appropriate to their status as God's representatives, worthy or otherwise, on earth.6. Pascal and Human ExistenceWhile it would be anachronistic to describe Pascal as an existentialist, one of the most abiding features of his work is the philosophical reflection on the radical contingency of human affairs that emerges in the final years of his life. He used these reflections to puncture the pride, arrogance and self-love of those who thought of themselves as superior to the vicissitudes of human life. Cromwell provided a contemporary illustration by his fall from power due to a relatively common illness. ‘Cromwell would have ravaged the whole of Christendom; the royal family was lost, and his own family was about to become all-powerful, except for a little grain of sand that lodged in his bladder. Even Rome was about to tremble beneath him. Once this little piece of stone became lodged there, he died, his family was disgraced, peace was established all round, and the king was restored’ (Fragment 632: II, 799). Many of Pascal's intuitions along these lines were almost a commonplace in the period, especially among Calvinist theologians. They were inspired in part by a growing acceptance within cosmology of the infinite extent of the universe and, in contrast, the relative finitude of individual human lives. They owed even more to a theological perspective that claimed to represent human affairs from God's perspective, including the absolute will by which He predestines individuals for salvation or eternal perdition. Pascal's distinctive contribution was to capture some of these insights in elegant, pithy phrases that matched the status of the Pensées as a personal notebook. Fragment 104, for example, compares a human life to a ‘thinking reed.’ ‘It is not in space that I should search for my dignity, but in the control of my thoughts… . The universe comprehends me by space and engulfs me like a point; by means of thought, I can comprehend it’ (II, 574).One could question the validity of considering the value of finite beings from the naturalistic perspective of an infinite universe, or even the conceivability of a divine perspective that, according to Pascal, is naturally inaccessible to finite minds. Given his extremely poor health and the expressions of abandonment that emerge from his writings, one cannot avoid considering whether Pascal's choice of ‘wretchedness’ (la misère) as a sub-title for one group of ‘thoughts’ reflected his personal experiences. ‘The greatness of human beings consists in their ability to know their wretchedness’ (Fragment 105: II, 574). Pascal's rejection of any naturalistic explanation of the human mind or soul, his emphasis on dread of an unknown future (in his case, whether we are saved or

damned), the apparent insignificance of human existence, and the experience of being dominated by political and natural forces that far exceed our limited powers, strike a chord of recognition with some of the existentialist writings that emerged in Europe following the Second World War. This was philosophy in a different register. Rather than speculate about abstract matters which were inaccessible to most of his contemporaries, Pascal invites his readers to recognize the description of his personal experiences as resonating with their own. While emphasizing the natural insignificance of individual human lives, he did not conclude that human existence was absurd. He pointed instead, as Christian existentialists have done since, to a source of meaning that would transcend the limitations of our thought. Access, however, was strictly limited to those to whom God gave the gift of religious faith.BibliographyPascal's Works

Pascal, B. (1963). Oeuvres complètes (L. Lafuma, Ed.). Paris: Éditions du Seuil. Pascal, B. (1964–92). Oeuvres complètes (J. Mesnard, Ed.). 4 vols. published to date of a projected

seven-volume edition. Paris: Desclée de Brouwer. Pascal, B. (1998–2000). Oeuvres complètes (M. Le Guern, Ed.). 2 vols. Paris: Gallimard. Pascal, B. (1973). The Physical Treatises of Pascal (I.H. B. and A. G. H. Spiers, trans.). New York;

Octagon Books. Pascal, B. (1991). Pensées (P. Sellier, Ed.). Paris: Bords. Pascal. B. (1967). The Provincial Letters (A. J. Krailsheimer, trans.). Harmondsworth, UK: Penguin. Pascal, B. (1995). Pensées and other writings (H. Levi, trans.). Oxford: Oxford University Press.

Related Early Works Arnauld, A. (1703). De la fréquente communion, ou les sentimens des Peres, des papes, et des

Conciles, touchant l'usage des Sacrements de Penitence & d'Eucharistie sont fidellement exposez. Lyon: Plaignard. (1st edn. 1644).

Arnauld, A. and P. Nicole (1993). La Logique ou l'art de penser, 2nd edn. (P. Clair and F. Girbal eds). Paris: Vrin. Logic or the Art of Thinking (J. Buroker, trans.). Cambridge: Cambridge University Press, 1996.

Jansenius, C. (1640). Augustinus. Louvain. Jansenius, C. (2004). Discours de la réformation de l'homme intérieur. (1st edn. 1642). Paris: Éditions

Manucius. Recommended Secondary Literature

Carraud, V. (1992). Pascal et la philosophie. Paris: Presses universitaires de France. Cléro, J-P. (1999). Les Pascals à Rouen 1640–48. Rouen: l'Université de Rouen. Cole, J. R. (1995). Pascal: The Man and his Two Loves. New York and London: New York University

Press. Davidson, H. and P. H. Dubé, eds. (1975). A Concordance to Pascal's Pensées. Ithaca and London:

Cornell University Press. Edwards, A. W. F. (1987/2002). Pascal's Arithmetical Triangle. London: Griffin; Oxford: Oxford University

Press; Baltimore, MD: Johns Hopkins University Press. Ferreyrolles, G. (1984). Pascal et la raison du politique. Paris: Presses universitaires de France. Hacking, I. (1975). The Emergence of Probability. Cambridge: Cambridge University Press. Hammond, N., ed. (2003). The Cambridge Companion to Pascal. Cambridge: Cambridge University

Press. Kremer, E. J. ed. (1994). The Great Arnauld and Some of his Philosophical Correspondents. Toronto

and London: University of Toronto Press. Le Guern, M. (2003). Pascal et Arnauld. Paris: Champion. Maire, A. ed. (1925–27). Bibliographie générale des oeuvres de Blaise Pascal. 5 vols. Paris: H. Leclerc. Moriarty, Michael (2006). Fallen Nature, Fallen Selves: Early Modern French Thought II. Oxford: Oxford

University Press. Sellier, P. (1970). Pascal et Saint Augustin. Paris: Armand Colin.

Related EntriesArnauld, Antoine | Augustine, Saint | Descartes, René | Malebranche, Nicolas | Mersenne, Marin | Montaigne, Michel de | occasionalism | Pascal's wager Copyright © 2007 by Desmond Clarke <clarkedesmond@gmail.com>

http://www.custom-essay.net/essay-encyclopedia/Blaise-Pascal-Essay.htm

Encyclopedia of the essay Pascal, Blaise

French, 1623-1662

Although known primarily as a scientist, mathematician, and religious apologist, Blaise Pascal can also justly be seen as a major essayist. Much of his written output consists of polemical exchanges and discourses. The work that distinguishes him above all as an essayist is the Lettres provinciales (The Provincial Letters) . Appearing initially as a series of pamphlets between January 1656 and June 1657, the 18 letters were first published together, under the pseudonym of Louis de Montalte, in 1657. The reason for anonymity resulted from the highly flammable debate between two leading Catholic sects, the Jesuits (who had the support of the King, Louis XIV) and the Jansenists (whom Pascal was trying to defend). The Jansenists (never officially accepted by the Catholic Church) were named after Cornelius Jansenius ( 1587-1638), a Flemish theologian and Bishop of Ypres, whose posthumously published Augustinus (1640) was an attempt to vindicate the teaching of St. Augustine against the doctrines of more recent Jesuit theologians. The Jansenists, situated initially at a convent near Paris, known as Port-Royal des Champs, and then also in Paris itself at Port-Royal, based their beliefs on the doctrine of original sin. They argued that, since the Fall in the Garden of Eden, all humankind has been corrupted by sin. Their objection to the Jesuits stemmed from what they saw as the over-reliance of the Jesuits on human free will, to the detriment of divine grace. At the beginning of 1656, a defender of those at Port-Royal was badly needed. Antoine Amauld, a leading theologian at Port-Royal, was about to be censured by the Sorbonne for taking a stand on five so-called heretical propositions which were allegedly to be found in Jansenius' Augustinus . However, with the risk of imprisonment which the Port-Royal sympathizers ran if they were discovered to be the authors of any attack on the Jesuits, it was difficult to find someone who could champion their cause. Pascal turned out to be the ideal person. At that time he was famous only for his mathematical and scientific gifts, and was not known for his links with Port-Royal; it was therefore easier for him to preserve his anonymity. Another great advantage was that, because he was not trained as a theologian, he could write with a freshness and immediacy that was appealing and understandable to a wider audience, not simply to those interested in the intricacies of the religious debate. It is this seeming spontaneity which has maintained the appeal of The Provincial Letters to this day. The letters can be divided into two main groups: letters 1-10 and letters 11-18. In the first group, we find an interplay between a naive persona (often referred to as the Louis de Montalte figure) writing to his friend in the provinces, a Jansenist friend, and some Jesuit priests. By employing the interview technique (especially in letters 4-10), Pascal manages to make the Jesuits condemn themselves with their own words. He also achieves this by the highly selective quotation of various Jesuit writers. The comedy of the situation is heightened by the contrast between Pascal's portrayal of an irascible and buffoon-like Jesuit central figure and the quietly knowing and reasonable Jansenist friend. Much of the debate in the early letters surrounds the Jesuits' use of terms like "proximate power" and "sufficient grace," which, according to Pascal, enabled them to explain away their pursuit of morally reprehensible lives. Whereas the Jesuits believed that human beings had sufficient grace within them to be saved, Pascal followed the more rigorous idea of "efficacious grace," where God alone is seen as capable of bestowing grace upon human beings. Pascal had elaborated upon these ideas in his Écrits sur la grâce (wr. c. 1657-58; Writings on grace), in which he contrasts the "disciples of St. Augustine" (Jansenists) with the Calvinists and the Jesuits (or "Molinists," as he calls them, named after the Spanish Jesuit theologian, Molina). In letters 11-18, all pretense of a real exchange between different personae is dropped. The speaker (now much more knowledgeable) engages in direct polemic with the Jesuits as a whole. In the final two letters (17-18), the attack is directed specifically at Père Annat, one of the leading Jesuits and the King's spiritual confessor. The reason for the shift in emphasis in letter 11 onward stemmed from the fact that the Jesuits themselves had launched a vigorous counterattack against the author of The Provincial Letters , and Pascal felt it necessary to respond more directly to accusations that he was making fun of religion by writing such satirical pamphlets. Many other shorter works also mark Pascal as an essayist. In addition to a large number of scientific treatises, there exist several writings on religious or related topics. Even the preface to his treatise on the vacuum, written in 1651 (long before his definitive conversion in 1654), contains a discussion of religious issues. In it he compares the value of recent research, where the use of reason (as in scientific experiments) is paramount, with other forms of knowledge, where the importance of tradition or authority (as in theology) is stressed.Between 1654 and 1656, Pascal wrote a number of significant short works. A document, known as the "Mémorial," which was found sewn into Pascal's clothing after his death, testifies to the conversion experience he underwent on the night of 23-24 November 1654. Another work that can be linked to the conversion, the " Entretien avec Monsieur de Saci " (wr. c. 1655; Conversation with Monsieur de Saci), contains an account by Nicolas Fontaine of the conversation Pascal had soon after his conversion with his spiritual director, Isaac Le Maistre de Saci, on the subject of the worldly writers Montaigne and Epictetus. Although first published only in 1728, the "Entretien" is generally accepted as authentic, and it is probable that Fontaine based his account on a written text (now lost) by Pascal. Another work, " De l'esprit géométrique " (wr. c. 1655; On the geometrical mind), concentrates on

different kinds of reasoning and reveals the influence of Descartes (much of whose philosophy Pascal would refute in his later religious writings). There is an interesting subsection of " De l'esprit géométrique " entitled De l'art de persuader " (On the art of persuasion), in which Pascal considers the importance of different persuasive methods, acknowledging moreover that rational methods are often less persuasive than those that appeal to the heart or will. He was to develop these ideas in his most celebrated work, the posthumously published Pensées (1670).Because the Pensées remained uncompleted at Pascal's death, it is uncertain what form the work would have taken. However, there is some evidence to suggest that Pascal would have juxtaposed different kinds of discourse, including fragmentary writings, maxims , letters, and dialogue . It is significant that Montaigne's Essais (1580, 1588) were a major influence on the Pensées, as the disparate ordering of the former can be discerned to some extent in the latter. However, one of Pascal's major purposes in writing the Pensées was to try and convince the non-believers and skeptics of his day, many of whom were admirers of Montaigne, of the necessity of religion, and Pascal deliberately attempts to distance himself from what he sees as the extreme egotism of Montaigne.A number of longer passages in the Pensées constitute essays in their own right. The most notorious (and most widely interpreted) section is that known as the Wager, where Pascal uses various mathematical arguments to convince the reader of the necessity to bet in favor of the existence of God. One long passage on the "disproportion de l'homme" (disproportion of man) depicts man as caught between two extremes of infinity and nothingness. Another section chronicles the debate between pyrrhonists (or skeptics) and dogmatists (or rationalists). The conflict between these leading sects is used by Pascal to demonstrate the contradictions which abound in human philosophy, contradictions which he argues can only be resolved by a recognition of original sin. Pascal also discusses at length the dangers of "divertissement" (diversion), showing how the quest for entertainment distracts humans from reflecting upon their wretched state. The long fragments devoted to the three orders (material, intellectual, and spiritual) are typical of his methods in other extracts, where he speaks of a "renversement continuel du pour au contre" (constant swing from pro to contra). In the passages devoted to "raison des effets" (cause and effect), for example, he considers the different attitudes of a varied range of people to appearances, showing how different kinds of people come to the same conclusion but for different reasons.Pascal writes at length in the Pensées on the "puissances trompeuses" (deceptive powers) which cloud man's self-awareness and which can even create their own world, named by Pascal as "une seconde nature" (a second nature). Prominent among these are imagination, which has the strength to form its own ideal of such abstract notions as beauty, justice and happiness, self-love (amour-propre), which turns man away from love for God, and custom or habit, which plays a large part in determining social attitudes or choice of employment. Other long essay-like passages include those on the concupiscences (influenced by Augustine), human justice (largely influenced by Montaigne), and that known as "le mystère de Jésus" (the mystery of Jesus), where Pascal uses prosopopoeia to depict Christ as speaker in the fragment. Other essays in the Pensées, like those on miracles, might have been intended for separate publication.Among Pascal's lesser-known writings, there are a number of essays, such as "Sur la conversion du pécheur" (wr. c. 1653; Upon the sinner's conversion), which charts the different stages a sinner might encounter on the path toward recognition of God, and "Trois discours sur la condition des grands" (wr. c. 1650; Three discourses on the condition of men of noble estate), in which Pascal advises a young nobleman on the implications of his rank.Pascal's confrontational style has earned him many enemies as well as admirers over the centuries since his death. Significantly, Pascal himself has been the subject of essays by writers as diverse as Voltaire , Chateaubriand , Valéry , and T. S. Eliot .

NICHOLAS HAMMONDSee also Pensée Biography Born 19 June 1623 in Clermont-en-Auvergne (now ClermontFerrand). Moved with family to Paris, 1631, and to Rouen, 1640. Studied privately, tutored mostly by father. Scientist and mathematician; invented the "Pascaline," a machine performing mathematical calculations, 1642-52, and conducted experiments with the vacuum, 1646-48. Converted to Jansenism, 1646. Returned to Paris on father's second retirement, 1647; had second conversion, 23-24 November 1654, a mystical experience he described in the "Mémorial" document of faith, which was found sewn in his doublet on his death. Made occasional retreats to Jansenist community at Port-Royal des Champs, from 1655. Worked on a public transportation system for Paris, 1660-62. Died in Paris, 19 August 1662. Selected Writings Essays and Related Prose Lettres provinciales (18 letters), January 1656-June 1657; in book form (as Louis de Montalte), 1657; edited by Louis Cognet, 1965, and Michel Le Guern, 1987; as The Provincial Letters , translated by William Andrews, 1744, Thomas M'Crie, 1847, and A. J. Krailsheimer, 1966 Pensées de M. Pascal sur la religion, et sur quelques autres sujets, edited by Étienne Périer, 1670, revised edition, 1684, Voltaire (Condorcet Edition), 1778, A. P. Faugère, 1844, Louis Lafuma, 2 vols., 1947, Georges Brunet, 1956, Louis Marin, 1969, and Philippe Sellier, 1976; as Discours sur la religion, et quelques autres sujets, edited by Emmanuel Martineau, 1992; selections edited by André Comte-Sponville,

1992; many translations, including by J. Walker, 1688, H. F. Stewart, 1950, John Warrington, 1960, J. M. Cohen, 1961, Martin Turnell, 1962, A. J. Krailsheimer, 1966, and Honor Levi, 1995 Great Shorter Works of Pascal , translated by E. Cailliet and John C. Blankenagel , 1948 Selections , edited by Richard H. Popkin, 1989 The Mind on Fire (selections; various translators), edited by James M. Houston , 1989 Selected Readings , edited by Robert Van De Weyer, 1991 Other writings: scientific works and a life of Jesus.Collected works editions: Œuvres complètes, edited by Léon Brunschvicg, 14 vols., 1904-14; Œuvres complètes (Pléiade Edition), edited by Jacques Chevalier, 1954; Œuvres complètes (Intégrale Edition), edited by Louis Lafuma, 1963; Œeuvres complètes, edited by Jean Mesnard, 4 vols., 1964-92 (in progress). Bibliographies   Heller, Lane M., and Thérèse Goyet, Bibliographie Blaise Pascal (1960-1969) , Clermont-Ferrand: Adosa, 1989   Maire, Albert, Bibliographie générale des œuvres de Blaise Pascal, Paris: Giraud-Badin, 5 vols., 1925-27 Further Reading   Croquette, Bernard, Pascal et Montaigne: Étude des réminiscences des Essais dans l'œuvre de Pascal, Geneva: Droz, 1974   Davidson, Hugh M., Blaise Pascal , Boston: Twayne, 1983   Hammond, Nicholas, Playing with Truth: Language and the Human Condition in Pascal's Pensées , Oxford: Clarendon Press, 1994   Krailsheimer, A. J., Pascal , Oxford and New York: Oxford University Press, 1980   Mesnard, Jean, Les Pensées de Pascal, Paris: Société d'Édition d'Enseignement Supérieur, 1993 (original edition, 1976)   Norman, Buford, Portraits of Thought: Knowledge, Methods and Styles in Pascal , Columbus: Ohio State University Press, 1988   Parish, Richard, Pascal's Lettres provinciales: A Study in Polemic , Oxford: Clarendon Press, 1989   Rex, Walter E., Pascal's Provincial Letters: An Introduction , London: Hodder and Stoughton, 1977   Wetsel, David, Pascal and Disbelief: Catechesis and Conversion in the Pensées , Washington, D.C.: Catholic University of America Press, 1994

http://en.wikipedia.org/wiki/Blaise_PascalBlaise PascalFrom Wikipedia, the free encyclopediaBlaise Pascal (pronounced [bl ɛ z paskal] ), (June 19, 1623, in Clermont-Ferrand, France – August 19, 1662) was a French mathematician, physicist, and religious philosopher. He was a child prodigy who was educated by his father, a civil servant. Pascal's earliest work was in the natural and applied sciences where he made important contributions to the construction of mechanical calculators, the study of fluids, and clarified the concepts of pressure and vacuum by generalizing the work of Evangelista Torricelli. Pascal also wrote in defense of the scientific method.Pascal was a mathematician of the first order. He helped create two major new areas of research. He wrote a significant treatise on the subject of projective geometry at the age of sixteen, and later corresponded with Pierre de Fermat on probability theory, strongly influencing the development of modern economics and social science. Following Galileo and Torricelli, in 1646 he refuted Aristotle's followers who insisted that nature abhors a vacuum. His results caused many disputes before being accepted.In 1646, he and his sister Jacqueline converted to Jansenism.[1] His father died in 1651. Following a mystical experience in late 1654, he had his "second conversion", abandoned his scientific work, and devoted himself to philosophy and theology. His two most famous works date from this period: the Lettres provinciales and the Pensées, the former set in the conflict between Jansenists and Jesuits. In this year, he also wrote an important treatise on the arithmetic of triangles. Between 1658 and 1659 he wrote on the cycloid and its use in calculating the volume of solids.Pascal had poor health throughout his life and his death came just two months after his 39th birthday.[2]

Contents[hide]

1 Early life and education 2 Contributions to mathematics

o 2.1 Philosophy of mathematics 3 Contributions to the physical sciences 4 Adult life, religion, philosophy, and literature

o 4.1 Religious conversion o 4.2 Brush with death o 4.3 The Provincial Letters o 4.4 Miracle o 4.5 The Pensées o 4.6 Last works and death

5 Legacy 6 Other 7 Works 8 See also 9 References 10 Notes 11 External links

[edit] Early life and educationPascal lost his mother, Antoinette Begon, at the age of three. His father, Étienne Pascal (1588–1651), who also had an interest in science and mathematics, was a local judge and member of the "Noblesse de Robe". Pascal had two sisters, the younger Jacqueline and the elder Gilberte.In 1631, after the death of his wife, Étienne Pascal moved with his children to Paris. The newly-arrived family soon hired Louise Delfault, a maid who eventually became an instrumental member of the family. Étienne, who never remarried, decided that he alone would educate his children, for they all showed extraordinary intellectual ability, particularly his son Blaise. The young Pascal showed an amazing aptitude for mathematics and science. At the age of eleven, he composed a short treatise on the sounds of vibrating bodies, and Étienne responded by forbidding his son to further pursue mathematics until the age of fifteen so as not to harm his study of Latin and Greek. One day, however, Étienne found Blaise (now twelve) writing an independent proof that the sum of the angles of a triangle is equal to two right angles with a piece of coal on a wall. From then on, the boy was allowed to study Euclid; perhaps more importantly, he was allowed to sit in as a silent on-looker at the gatherings of some of the greatest mathematicians and scientists in Europe—such as Roberval, Desargues, Mydorge, Gassendi, and Descartes—in the monastic cell of Père Mersenne.Particularly of interest to Pascal was a work of Desargues on conic sections. Following Desargues' thinking, the sixteen-year-old Pascal produced, as a means of proof, a short treatise on what was called the "Mystic Hexagram", Essai pour les coniques ("Essay on Conics") and sent it—his first serious work of mathematics—to Père Mersenne in Paris; it is known still today as Pascal's theorem. It states that if a hexagon is inscribed in a circle (or conic) then the three intersection points of opposite sides lie on a line (called the Pascal line).Pascal's work was so precocious that Descartes, when shown the manuscript, refused to believe that the composition was not by the elder Pascal. When assured by Mersenne that it was, indeed, the product of the son not the father, Descartes dismissed it with a sniff: "I do not find it strange that he has offered demonstrations about conics more appropriate than those of the ancients," adding, "but other matters related to this subject can be proposed that would scarcely occur to a sixteen-year-old child."[3]

In France at that time offices and positions could be—and were—bought and sold. In 1631 Étienne sold his position as second president of the Cour des Aides for 65,665 livres.[4] The money was invested in a government bond which provided if not a lavish then certainly a comfortable income which allowed the Pascal family to move to, and enjoy, Paris. But in 1638 Richelieu, desperate for money to carry on the Thirty Year War, defaulted on the government's bonds. Suddenly Étienne Pascal's worth had dropped from nearly 66,000 livres to less than 7,300.Like so many others, Étienne was eventually forced to flee Paris because of his opposition to the fiscal policies of Cardinal Richelieu, leaving his three children in the care of his neighbor Madame Sainctot, a great beauty with an infamous past who kept one of the most glittering and intellectual salons in all France. It was only when Jacqueline performed well in a children's play with Richelieu in attendance that Étienne was pardoned. In time Étienne was back in good graces with the cardinal, and in 1639 had been appointed the king's commissioner of taxes in the city of Rouen — a city whose tax records, thanks to uprisings, were in utter chaos.

An early Pascaline on display at the Musée des Arts et Métiers, Paris.In 1642, in an effort to ease his father's endless, exhausting calculations, and recalculations, of taxes owed and paid, Pascal, not yet nineteen, constructed a mechanical calculator capable of addition and subtraction, called Pascal's calculator or the Pascaline. The Musée des Arts et Métiers in Paris and the Zwinger museum in Dresden, Germany, exhibit two of his original mechanical calculators. Though these machines are early forerunners to computer engineering, the calculator failed to be a great commercial success. Because it was extraordinarily expensive the Pascaline became little more than a toy, and status symbol, for the very rich both in France and throughout Europe. However, Pascal continued to make improvements to his design through the next decade and built fifty machines in total.[edit] Contributions to mathematics

Pascal's triangle. Each number is the sum of the two directly above it. The triangle demonstrates many mathematical properties in addition to showing binomial coefficients.Pascal continued to influence mathematics throughout his life. His Traité du triangle arithmétique ("Treatise on the Arithmetical Triangle") of 1653 described a convenient tabular presentation for binomial coefficients, now called Pascal's triangle. The triangle can also be represented:

0 1 2 3 4 5 6

0 1 1 1 1 1 1 1

1 1 2 3 4 5 6

2 1 3 6 10 15

3 1 4 10 20

4 1 5 15

5 1 6

6 1

He defines the numbers in the triangle by recursion: Call the number in the (m+1)st row and (n+1)st column tmn. Then tmn = tm-1,n + tm,n-1, for m = 0, 1, 2... and n = 0, 1, 2... The boundary conditions are tm, -1 = 0, t-1, n for m = 1, 2, 3... and n = 1, 2, 3... The generator t00 = 1. Pascal concludes with the proof, .In 1654, prompted by a friend interested in gambling problems, he corresponded with Fermat on the subject, and from that collaboration was born the mathematical theory of probabilities. The friend was the Chevalier de Méré, and the specific problem was that of two players who want to finish a game early and, given the current circumstances of the game, want to divide the stakes fairly, based on the chance each has of winning the game from that point. From this discussion, the notion of expected value was introduced. Pascal later (in the Pensées) used a probabilistic argument, Pascal's Wager, to justify belief in God and a virtuous life. The work done by Fermat and Pascal into the calculus of probabilities laid important groundwork for Leibniz' formulation of the infinitesimal calculus.[5]

After a religious experience in 1654, Pascal mostly gave up work in mathematics. However, after a sleepless night in 1658, he anonymously offered a prize for the quadrature of a cycloid. Solutions were offered by Wallis,

Huygens, Wren, and others; Pascal, under the pseudonym Amos Dettonville, published his own solution. Controversy and heated argument followed after Pascal announced himself the winner.[edit] Philosophy of mathematicsPascal's major contribution to the philosophy of mathematics came with his De l'Esprit géométrique ("On the Geometrical Spirit"), originally written as a preface to a geometry textbook for one of the famous "Petites-Ecoles de Port-Royal" ("Little Schools of Port-Royal"). The work was unpublished until over a century after his death. Here, Pascal looked into the issue of discovering truths, arguing that the ideal of such a method would be to found all propositions on already established truths. At the same time, however, he claimed this was impossible because such established truths would require other truths to back them up—first principles, therefore, cannot be reached. Based on this, Pascal argued that the procedure used in geometry was as perfect as possible, with certain principles assumed and other propositions developed from them. Nevertheless, there was no way to know the assumed principles to be true.Pascal also used De l'Esprit géométrique to develop a theory of definition. He distinguished between definitions which are conventional labels defined by the writer and definitions which are within the language and understood by everyone because they naturally designate their referent. The second type would be characteristic of the philosophy of essentialism. Pascal claimed that only definitions of the first type were important to science and mathematics, arguing that those fields should adopt the philosophy of formalism as formulated by Descartes.In De l'Art de persuader ("On the Art of Persuasion"), Pascal looked deeper into geometry's axiomatic method, specifically the question of how people come to be convinced of the axioms upon which later conclusions are based. Pascal agreed with Montaigne that achieving certainty in these axioms and conclusions through human methods is impossible. He asserted that these principles can only be grasped through intuition, and that this fact underscored the necessity for submission to God in searching out truths.[edit] Contributions to the physical sciences

Pascal's work in the fields of the study of hydrodynamics and hydrostatics centered on the principles of hydraulic fluids. His inventions include the hydraulic press (using hydraulic pressure to multiply force) and the syringe. By 1646, Pascal had learned of Evangelista Torricelli's experimentation with barometers. Having replicated an experiment which involved placing a tube filled with mercury upside down in a bowl of mercury, Pascal questioned what force kept some mercury in the tube and what filled the space above the mercury in the tube. At the time, most scientists contended that, rather than a vacuum, some invisible matter was present. This was based on the Aristotelian notion that creation was a thing of substance, whether visible or invisible; and this substance was forever in motion. Furthermore, "Everything that is in motion must be moved by something," Aristotle declared.[6] Therefore, to the Aristotelian trained scientists of Pascal's time, a vacuum was an impossibility. How so? As proof it was pointed out:

Light passed through the so-called "vacuum" in the glass tube. Aristotle wrote how everything moved, and must be moved by something. Therefore, since there had to be an invisible "something" to move the light through the glass tube, there

was no vacuum in the tube. Not in the glass tube or anywhere else. Vacuums—the absence of any and everything—were simply an impossibility.

Following more experimentation in this vein, in 1647 Pascal produced Experiences nouvelles touchant le vide ("New Experiments with the Vacuum"), which detailed basic rules describing to what degree various liquids could be supported by air pressure. It also provided reasons why it was indeed a vacuum above the column of liquid in a barometer tube.On September 19, 1648, after many months of Pascal's friendly but insistent prodding, Florin Périer, husband of Pascal's elder sister Gilberte, was finally to carry out the fact finding mission vital to Pascal's theory. The account, written by Périer, reads:"The weather was chancy last Saturday...[but] around five o'clock that morning...the Puy-de-Dôme was visible...so I decided to give it a try. Several important people of the city of Clermont had asked me to let them know when I would make the ascent...I was delighted to have them with me in this great work... "...at eight o'clock we met in the gardens of the Minim Fathers, which has the lowest elevation in town....First I poured sixteen pounds of quicksilver...into a vessel...then took several glass tubes...each four feet long and hermetically sealed at one end and opened at the other...then placed them in the vessel [of quicksilver]...I found the quick silver stood at 26" and 3½ lines above the quicksilver in the vessel...I repeated the experiment two more times while standing in the same spot...[they] produced the same result each time... "I attached one of the tubes to the vessel and marked the height of the quicksilver and...asked Father Chastin, one of the Minim Brothers...to watch if any changes should occur through the day...Taking the other tube and a portion of the quick silver...I walked to the top of Puy-de-Dôme, about 500 fathoms higher than the monastery, where upon experiment...found that the quicksilver reached a height of only 23" and 2 lines...I repeated the experiment five times with care...each at different points on the summit...found the same height of quicksilver...in each case..."[7]

Pascal replicated the experiment in Paris by carrying a barometer up to the top of the bell tower at the church of Saint-Jacques-de-la-Boucherie, a height of about fifty meters. The mercury dropped two lines. These, and other lesser experiments carried out by Pascal, were hailed throughout Europe as establishing the principle and value of the barometer.In the face of criticism that some invisible matter must exist in Pascal's empty space, Pascal, in his reply to Estienne Noel, gave one of the seventeenth century's major statements on the scientific method: "In order to show that a hypothesis is evident, it does not suffice that all the phenomena follow from it; instead, if it leads to something contrary to a single one of the phenomena, that suffices to establish its falsity." His insistence on the existence of the vacuum also led to conflict with other prominent scientists, including Descartes.[edit] Adult life, religion, philosophy, and literature

“ For after all what is man in nature? A nothing in relation to infinity, all in relation to nothing, a central point between nothing and all and infinitely far from understanding either. The ends of things and their beginnings are impregnably concealed from him in an impenetrable secret. He is equally incapable of seeing the nothingness out of which he was drawn and the infinite in which he is engulfed. ”

Blaise Pascal, Pensées #72 [edit] Religious conversionBiographically, two basic influences led him to his conversion: sickness and Jansenism. From as early as his eighteenth year, Pascal suffered from a nervous ailment that left him hardly a day without pain. In 1647, a paralytic attack so disabled him that he could not move without crutches. His head ached, his bowels burned, his legs and feet were continually cold, and required wearisome aids to circulate the blood; he wore stockings steeped in brandy to warm his feet. Partly to get better medical treatment, he moved to Paris with his sister Jacqueline. His health improved, but his nervous system had been permanently damaged. Henceforth, he was subject to deepening hypochondria, which affected his character and his philosophy. He became irritable, subject to fits of proud and imperious anger, and seldom smiled.[8]

In the winter of 1646, Pascal's 58 year-old father broke his hip when he slipped and fell on an icy street of Rouen; given the man's age and the state of medicine in the 17th century, a broken hip could be a very serious condition, perhaps even fatal. Rouen was home to two of the finest doctors in France: Monsieur Doctor Deslandes and Monsieur Doctor de La Bouteillerie. The elder Pascal "would not let anyone other than these men attend him...It was a good choice, for the old man survived and was able to walk again..."[9] But treatment and rehabilitation took three months, during which time La Bouteillerie and Deslandes had become household guests.Both men were followers of Jean Guillebert, proponent of a splinter group from the main body of Catholic teaching known as Jansenism. This still fairly small sect was making surprising inroads into the French Catholic community at that time. It espoused rigorous Augustinism. Blaise spoke with the doctors frequently, and upon his successful treatment of Étienne, borrowed works by Jansenist authors from them. In this period, Pascal experienced a sort of "first conversion" and began to write on theological subjects in the course of the following year.Pascal fell away from this initial religious engagement and experienced a few years of what he called[citation needed] a "worldly period" (1648–54). His father died in 1651 and left his inheritance to Pascal and Jacqueline, of which Pascal acted as her conservator. Jacqueline announced that she would soon become a postulant in the Jansenist convent of Port-Royal. Pascal was deeply affected and very sad, not because of her choice, but because of his chronic poor health; he too needed her."Suddenly there was war in the Pascal household. Blaise pleaded with Jacqueline not to leave, but she was adamant. He commanded her to stay, but that didn't work, either. At the heart of this was...Blaise's fear of abandonment...if Jacqueline entered Port-Royal, she would have to leave her inheritance behind...[but] nothing would change her mind."[10]

By the end of October in 1651, a truce had been reached between brother and sister. In return for a healthy annual stipend, Jacqueline signed over her part of the inheritance to her brother. Gilberte had already been given her inheritance in the form of a dowry. In early January, Jacqueline left for Port-Royal. On that day, according to Gilberte concerning her brother, "He retired very sadly to his rooms without seeing Jacqueline, who was waiting in the little parlor..."[11] In early June of 1653, after what must have seemed like endless badgering from Jacqueline, Pascal formally signed over the whole of his sister's inheritance to Port-Royal, which, to him, "had begun to smell like a cult."[12] With two-thirds of his father's estate now gone, the 29 year old Pascal was now consigned to genteel poverty.For a while, Pascal pursued the life of a bachelor. He showed strong interest in one woman while in Auvergne. He referred to her as the "Sappho of the countryside."[13] During this time, Pascal wrote Discours sur les passions de l'amour ("Conversation about the Passions of Love") and apparently contemplated marriage — which he was later to describe as "the lowest of the conditions of life permitted to a Christian."[14] Jacqueline reproached him for

his frivolity and prayed for his reform.[citation needed] During visits to his sister at Port-Royal in 1654, he displayed contempt for affairs of the world but was not drawn to God.[15]

[edit] Brush with deathOn October 1654, Pascal is said to have been involved in an accident at the Neuilly-sur-Seine bridge where the horses plunged over the parapet and the carriage nearly followed them. Fortunately, the reins broke and the coach hung halfway over the edge. Pascal and his friends emerged unscathed, but the sensitive philosopher, terrified by the nearness of death, fainted away and remained unconscious for some time. On 23 November 1654, between 10:30 and 12:30 at night, Pascal had an intense religious vision and immediately recorded the experience in a brief note to himself which began: "Fire. God of Abraham, God of Isaac, God of Jacob, not of the philosophers and the scholars…" and concluded by quoting Psalm 119:16: "I will not forget thy word. Amen." He seems to have carefully sewn this document into his coat and always transferred it when he changed clothes; a servant discovered it only by chance after his death.[16] This piece is now known as the Memorial. The story of the carriage accident as having led to the experience described in the Memorial is disputed by some scholars.[17] His belief and religious commitment revitalized, Pascal visited the older of two convents at Port-Royal for a two-week retreat in January 1655. For the next four years, he regularly travelled between Port-Royal and Paris. It was at this point immediately after his conversion when he began writing his first major literary work on religion, the Provincial Letters[edit] The Provincial LettersMain article: Lettres provincialesBeginning in 1656, Pascal published his memorable attack on casuistry, a popular ethical method used by Catholic thinkers in the early modern period (especially the Jesuits, and in particular Antonio Escobar). Pascal denounced casuistry as the mere use of complex reasoning to justify moral laxity and all sorts of sins. His method of framing his arguments was clever: the Provincial Letters pretended to be the report of a Parisian to a friend in the provinces on the moral and theological issues then exciting the intellectual and religious circles in the capital. Pascal, combining the fervor of a convert with the wit and polish of a man of the world, reached a new level of style in French prose. The 18-letter series was published between 1656 and 1657 under the pseudonym Louis de Montalte and incensed Louis XIV. The king ordered that the book be shredded and burnt in 1660. In 1661, in the midsts of the formulary controversy, the Jansenist school at Port-Royal was condemned and closed down; those involved with the school had to sign a 1656 papal bull condemning the teachings of Jansen as heretical. The final letter from Pascal, in 1657, had defied the Pope himself, provoking Alexander VII to condemn the letters. But that didn't stop all of educated France from reading them. Even Pope Alexander, while publicly opposing them, nonetheless was persuaded by Pascal's arguments. He condemned "laxism" in the church and ordered a revision of casuistical texts just a few years later (1665–66).Aside from their religious influence, the Provincial Letters were popular as a literary work. Pascal's use of humor, mockery, and vicious satire in his arguments made the letters ripe for public consumption, and influenced the prose of later French writers like Voltaire and Jean-Jacques Rousseau.Wide praise has been given to the Provincial Letters. Voltaire called the Letters "the best-written book that has yet appeared in France."[18] And when Bossuet was asked what book he would rather have written had he not written his own, he answered, the Provincial Letters of Pascal.[19]

[edit] MiracleWhen Pascal was back in Paris just after overseeing the publication of the last Letter, his religion was reinforced by the close association to an apparent miracle in the chapel of the Port-Royal nunnery. His 10-year-old niece, Marguerite Périer, was suffering from a painful fistula lacrymalis that exuded noisome pus through her eyes and nose—an affliction the doctors pronounced hopeless. Then, on March 24, 1657, a believer presented to Port-Royal what he and others claimed to be a thorn from the crown that had tortured Christ. The nuns, in solemn ceremony and singing psalms, placed the thorn on their altar. Each in turn kissed the relic, and one of them, seeing Marguerite among the worshipers, took the thorn and with it touched the girl's sore. That evening, we are told, Marguerite expressed surprise that her eye no longer pained her; her mother was astonished to find no sign of the fistula; a physician, summoned, reported that the discharge and swelling had disappeared. He, not the nuns, spread word of what he termed a miraculous cure. Seven other physicians who had had previous knowledge of Marguerite's fistula signed a statement that in their judgment a miracle had taken place. The diocesan officials investigated, came to the same conclusion, and authorized a Te Deum Mass in Port-Royal. Crowds of believers came to see and kiss the thorn; all of Catholic Paris acclaimed a miracle. Later, both pro and anti Jansenists used this well-documented miracle to their defense. In 1728, Pope Benedict XIII referred to the case as proving that the age of miracles had not passed.Pascal made himself an armorial emblem of an eye surrounded by a crown of thorns, with the inscription Scio cui credidi—"I know whom I have believed."[20] His beliefs renewed, he set his mind to write his final, unfinished testament, the Pensées.[edit] The PenséesMain article: Pensées

Pascal's most influential theological work, referred to posthumously as the Pensées ("Thoughts"), was not completed before his death. It was to have been a sustained and coherent examination and defense of the Christian faith, with the original title Apologie de la religion Chrétienne ("Defense of the Christian Religion"). What was found upon sifting through his personal items after his death were numerous scraps of paper with isolated thoughts, grouped in a tentative, but telling, order. The first version of the detached notes appeared in print as a book in 1670 titled Pensées de M. Pascal sur la religion, et sur quelques autres sujets ("Thoughts of M. Pascal on religion, and on some other subjects") and soon thereafter became a classic. One of the Apologie's main strategies was to use the contradictory philosophies of skepticism and stoicism, personalized by Montaigne on one hand, and Epictetus on the other, in order to bring the unbeliever to such despair and confusion that he would embrace God. This strategy was deemed quite hazardous by Pierre Nicole, Antoine Arnauld and other friends and scholars of Port-Royal, who were concerned that these fragmentary "thoughts" might lead to skepticism rather than to piety. Henceforth, they concealed the skeptical pieces and modified some of the rest, lest King or Church should take offense[21] for at that time the persecution of Port-Royal had ceased, and the editors were not interested in a renewal of controversy. Not until the nineteenth century were the Pensées published in their full and authentic text.

Wikisource has original text related to this article: PenséesPascal's Pensées is widely considered to be a masterpiece, and a landmark in French prose. When commenting on one particular section (Thought #72), Sainte-Beuve praised it as the finest pages in the French language.[22] Will Durant, in his 11-volume, comprehensive The Story of Civilization series, hailed it as "the most eloquent book in French prose."[23] In Pensées, Pascal surveys several philosophical paradoxes: infinity and nothing, faith and reason, soul and matter, death and life, meaning and vanity—seemingly arriving at no definitive conclusions besides humility, ignorance, and grace. Rolling these into one he develops Pascal's Wager.[edit] Last works and deathT. S. Eliot described him during this phase of his life as "a man of the world among ascetics, and an ascetic among men of the world." Pascal's ascetic lifestyle derived from a belief that it was natural and necessary for man to suffer. In 1659, Pascal, whose health had never been good, fell seriously ill. During his last years, he frequently tried to reject the ministrations of his doctors, saying, "Sickness is the natural state of Christians."[24]

Louis XIV suppressed the Jansenist movement at Port-Royal in 1661. In response, Pascal wrote one of his final works, Écrit sur la signature du formulaire ("Writ on the Signing of the Form"), exhorting the Jansenists not to give in. Later that year, his sister Jacqueline died, which convinced Pascal to cease his polemics on Jansenism. Pascal's last major achievement, returning to his mechanical genius, was inaugurating perhaps the first bus line, moving passengers within Paris in a carriage with many seats.In 1662, Pascal's illness became more violent. Aware that his health was fading quickly, he sought a move to the hospital for incurable diseases, but his doctors declared that he was too unstable to be carried. In Paris on August 18, 1662, Pascal went into convulsions and received extreme unction. He died the next morning, his last words being "May God never abandon me," and was buried in the cemetery of Saint-Étienne-du-Mont.[24]

An autopsy performed after his death revealed grave problems with his stomach and other organs of his abdomen, along with damage to his brain. Despite the autopsy, the cause of his continual poor health was never precisely determined, though speculation focuses on tuberculosis, stomach cancer, or a combination of the two.[25] The headaches which afflicted Pascal are generally attributed to his brain lesion.[edit] LegacyIn honor of his scientific contributions, the name Pascal has been given to the SI unit of pressure, to a programming language, and Pascal's law (an important principle of hydrostatics), and as mentioned above, Pascal's triangle and Pascal's wager still bear his name.Pascal's development of probability theory was his most influential contribution to mathematics. Originally applied to gambling, today it is extremely important in economics, especially in actuarial science. John Ross writes, "Probability theory and the discoveries following it changed the way we regard uncertainty, risk, decision-making, and an individual's and society's ability to influence the course of future events."[26] However, it should be noted that Pascal and Fermat, though doing important early work in probability theory, did not develop the field very far. Christiaan Huygens, learning of the subject from the correspondence of Pascal and Fermat, wrote the first book on the subject. Later figures who continued the development of the theory include Abraham de Moivre and Pierre-Simon Laplace.In literature, Pascal is regarded as one of the most important authors of the French Classical Period and is read today as one of the greatest masters of French prose. His use of satire and wit influenced later polemicists. The content of his literary work is best remembered for its strong opposition to the rationalism of René Descartes and simultaneous assertion that the main countervailing philosophy, empiricism, was also insufficient for determining major truths.

[edit] OtherIn France, a prestigious annual competition is held for outstanding international scientists to conduct their research in the Ile de France region named after Pascal (the Blaise Pascal Chair).In Canada, there is an annual math contest named in his honour. The Pascal Contest is open to any student in Canada who is fifteen years or under and is in grade nine or lower.A discussion of Pascal figures prominently in the film My Night at Maud's by the French director Éric Rohmer.Roberto Rossellini directed a filmed biopic (entitled Blaise Pascal) which originally aired on Italian television in 1971. Pierre Arditi starred as Pascal. Pascal was a subject for the first edition of the 1984 BBC Two documentary, "The Sea of Faith", presented by Don Cupitt (see Sea of Faith: Television series).The writer Thomas Bernhard (of Austria) references Pascal many times in his works.[edit] Works

Essai pour les coniques (1639) Experiences nouvelles touchant le vide (1647) Traité du triangle arithmétique (1653) Lettres provinciales (1656–57) De l'Esprit géométrique (1657 or 1658) Écrit sur la signature du formulaire (1661) Pensées (incomplete at death)

[edit] See also Scientific Revolution

[edit] References Broome, JH. Pascal. ISBN 0-7131-5021-1 Davidson, Hugh M. Blaise Pascal. Boston: Twayne Publishers, 1983. Farrell, John. "Pascal and Power". Chapter seven of Paranoia and Modernity: Cervantes to Rousseau

(Cornell UP, 2006). Goldmann, Lucien , The hidden God; a study of tragic vision in the Pensees of Pascal and the tragedies

of Racine (original ed. 1955, Trans. Philip Thody. London: Routledge, 1964) Miel, Jan. Pascal and Theology. Baltimore: John Hopkins University Press, 1969. Muir, Jane. Of Men and Numbers. New York: Dover Publications, Inc, 1996. ISBN 0-486-28973-7 Encyclopedia of Philosophy, 1967 edition, s.v. "Pascal, Blaise." Pascal, Blaise. Oeuvres complètes. Paris: Seuil, 1960. Pascal, Blaise. Oeuvres complètes. Jean Mesnard, ed. 4 vols have appeared. Paris: Desclée-Brouwer,

1964- [edit] Notes

1. ̂ "Blaise Pascal". Catholic Encyclopedia. http://www.newadvent.org/cathen/11511a.htm. Retrieved on 2009-02-23.

2. ̂ Hald, Anders A History of Probability and Statistics and Its Applications before 1750, (Wiley Publications, 1990) pp.44

3. ̂ The Story of Civilization: Volume 8, "The Age of Louis XIV" by Will & Ariel Durant; chapter II, subsection 4.1 p.56)

4. ̂ Connor, James A., Pascal's Wager(HarperCollins, NY, 2006) p.42 5. ̂ The Mathematical Leibniz 6. ̂ Aristotle,Physics,VII,1. 7. ̂ Périer to Pascal, September 1647,Œuves completes de Pascal, 2:682. 8. ̂ Sainte-Beuve, Port-Royal, I, 89. 9. ̂ Connor, James A. Pascal's Wager (HarperCollins, 2006)p.70 10. ̂ Miel p.122 11. ̂ Jacqueline Pascal, "Memoir" p. 87 12. ̂ Miel p.124 13. ̂ Pascal, Pensées, Havet ed. Introd., p. civ. 14. ̂ Mesnard, Pascal, 57. 15. ̂ Encyclopedia of Philosophy, 52. 16. ̂ Oeuvres complètes, 618. 17. ̂ MathPages, http://www.mathpages.com/.   .   . 18. ̂ Voltaire, Age of Louis XIV 424, 358. 19. ̂ Voltaire, Age of Louis XIV 359. 20. ̂ Sainte-Beuve, Port-Royal, III, 173f.; Beard, Charles, Port-Royal, I 84. 21. ̂ Pascal, Pensées, Introduction, p. xxviii; Mesnard, Pascal, 137–138. 22. ̂ Sainte-Beuve, Seventeenth Century, 174.

23. ̂ The Story of Civilization: Volume 8, "The Age of Louis XIV" by Will & Ariel Durant, chapter II, Subsection 4.4 (pg. 66)

24. ^ a b Muir, 104. 25. ̂ Muir, 103. 26. ̂ Pascal's legacy

[edit] External linksFind more about Blaise Pascal on Wikipedia's sister projects:

Definitions from WiktionaryTextbooks from WikibooksQuotations from WikiquoteSource texts from WikisourceImages and media from CommonsNews stories from WikinewsLearning resources from Wikiversity

Pascal's Memorial in orig. French/Latin and modern English, trans. Elizabeth T. Knuth. Etext of Pascal's Pensées (English, in various formats) Etext of Pascal's Lettres Provinciales (English) Etext of a number of Pascal's minor works (English translation) including, among others, De l'Esprit

géométrique and De l'Art de persuader. "Pascal's Legacy" , an article by John Ross on the influence of Pascal's probability theory. Biography, Bibliography. (in French) The Blaise Pascal School of Computing Sciences at Euclid University Works by Blaise Pascal at Project Gutenberg Blaise Pascal featured on the 500 French Franc banknote in 1977. Blaise Pascal's works : text, concordances and frequency lists  "Blaise Pascal". Catholic Encyclopedia. New York: Robert Appleton Company. 1913.

http://en.wikisource.org/wiki/Catholic_Encyclopedia_(1913)/Blaise_Pascal. Blaise Pascal College No.70 : A Rosicrucian (SRIA) college named after Pascal. Primary texts and discussions relating to the theology and history of Pascal and Jansenism O'Connor, John J. ; Robertson, Edmund F., "Blaise Pascal", MacTutor History of Mathematics archive Middle School Mathematician Project Short biography of Pascal by middle school students.

http://en.wikipedia.org/wiki/Pens%C3%A9esPenséesFrom Wikipedia, the free encyclopediaThe Pensées (literally, "thoughts") represented a defense of the Christian religion by Blaise Pascal, the renowned 17th century philosopher and mathematician. Pascal's religious conversion led him into a life of asceticism, and the Pensées was in many ways his life's work."Pascal's Wager" is found here. The Pensées is in fact a name given posthumously to his fragments, which he had been preparing for an Apology of Christian Religion which was never completed.Although they appear to consist of ideas and jottings, some of which are incomplete, it is believed that Pascal had, prior to his untimely death in 1662, already planned out the order of the book. Those responsible for his effects, failing to recognise the basic structure of the work, handed them over to be edited, and they were published in 1670.[1] The first English translation was made in 1803 by Thomas Chevalier, a British surgeon of French Huguenot descent.[2][3] It was not until the beginning of the 20th century that scholars began to understand Pascal's intention. In the 1990s, decisive philological achievements were made, and the edition by Philippe Sellier of the book contains his "thoughts" in more or less the order he left them.Several attempts have been made to arrange the notes systematically; notable editions include those of Brunschvicg, Louis Lafuma, and (most recently) Sellier. (See, also, the monumental edition of his Oeuvres complètes (1964–1991), which is known as the Tercentenary Edition and was realized by Jean Mesnard;[4] this edition reviews the dating, history, and critical bibliography of each of Pascal's texts.) Although Brunschvicg tried to classify the posthume fragments according to themes, recent research has prompted Sellier to choose entirely different classifications, as Pascal often examined the same event or example through many different lenses [5].The original layout of the individual notes was in fact recorded in situ, although this was not reflected in published editions of the work until recently, because the colleagues of Pascal who edited his notes after his death switched the order of the book's two main sections. Early editions led off with the traditional Christian content, leaving Pascal's reflections on the human condition until the end. The structure of the apology Pascal intended is best described by H. F. Stewart D.D. in the preface to his translation of the Pensees: Part I shows

"from Nature" that man is wretched without God, Part II shows "from Scripture" that Jesus is the Redeemer of mankind. Part I subdivides into Ia (man without God) and Ib (man with God) to show man's inherent wretchedness. The themes of Part I are largely in the tone of vanitas mundi, after the tradition of the Hebrew Bible's book of Ecclesiastes, while the many short maxims inserted into the text are reminiscent of the Book of Proverbs.Contents[hide]

1 Quotations o 1.1 On the abysses o 1.2 On reason o 1.3 On heart and head o 1.4 On soul and body o 1.5 On Man's fallen nature o 1.6 On vanity o 1.7 Yet Man is noble o 1.8 Regarding the Wager o 1.9 On Futility o 1.10 The mystery of God o 1.11 On the Bible o 1.12 On atheists

2 See also 3 Texts 4 References

[edit] Quotations[edit] On the abysses

Wikiquote has a collection of quotations related to: Pensées

"Let man contemplate Nature entire in her full and lofty majesty; let him put far from his sight the lowly objects that surround him; let him regard that blazing light, placed like an eternal lamp to illuminate the world; let the earth appear to him but a point within the vast circuit which that star describes; and let him marvel that this immense circumference is itself but a speck from the viewpoint of the stars that move in the firmament. And if our vision is stopped there, let imagination pass beyond... All this visible world is but an imperceptible element in the great bosom of nature. No thought can go so far... It is an infinite sphere whose center is everywhere, and whose circumference is nowhere. This is the most perceivable feature of the almightiness of God, so that our imagination loses itself in this thought.""The eternal silence of these infinite spaces frightens me."

Le silence éternel de ces espaces infinis m'effraie.[6] "He who sees himself thus will be frightened by himself, and, perceiving himself sustained... between these two abysses of infinity and nothing, will tremble... and will be more disposed to contemplate these marvels in silence than to explore them with presumption. For in the end, what is man in nature? A nothing in respect to the infinite, everything in respect to the nothing, a halfway between nothing and all. Infinitely far from comprehending the extremes, both the end and the beginning or principle of things are invincibly hidden in an impenetrable secret; he is equally incapable of seeing the nothing whence he has been drawn, and the infinite in which he is engulfed."*

* "The French language," said Sainte-Beuve, "has no finer pages than the simple and severe lines of this incomparable picture." [7]

[edit] On reason"The wisest reason takes as her own principles those which the imagination of man has everywhere rashly introduced.""Nothing is so conformable to reason as to disavow reason.""To make light of philosophy is to be a true philosopher."[edit] On heart and head"The heart has its reasons, of which reason knows nothing."

Le cœur a ses raisons que la raison ne connaît pas. [edit] On soul and body"It is impossible that our rational part should be other than spiritual; and if any one maintain that we are simply corporeal, this would far more exclude us from the knowledge of things, there being nothing so inconceivable as to say that matter knows itself. It is impossible to imagine how it should know itself."

"What a Chimera is man! What a novelty, a monster, a chaos, a contradiction, a prodigy! Judge of all things, an imbecile worm; depository of truth, and sewer of error and doubt; the glory and refuse of the universe. Who shall unravel this confusion?"Quelle chimère est-ce donc que l'homme? quelle nouveauté, quel monstre, quel chaos, quel sujet de contradictions, quel prodige? Juge de toutes choses, imbécile ver de terre, dépositaire du vrai, cloaque d'incertitude et d'erreur, gloire et rebut de l'univers. Qui démêlera cet embrouillement?[edit] On Man's fallen nature"Man is only a disguise, a liar, a hypocrite, both to himself and to others."

"How hollow is the heart of man, and how full of excrement!"[edit] On vanity"We would never travel on the sea if we had no hope of telling about it later... We lose our lives with joy provided people talk about it... Even philosophers wish for admirers."[edit] Yet Man is noble"The grandeur of man is great in that he knows himself to be miserable.""Man is but a reed, the most feeble (thing) in nature; but he is a thinking reed.* The entire universe need not arm itself in order to crush him; a vapor, a drop of water, suffices to kill him. But when (even if) the universe would (were to) crush him, man would (still) yet be more noble than that which kills him, because he knows that he is dying (that he dies) and the advantage (which) the universe has over him; the universe knows nothing of it (of this)."

* L'homme n'est qu'un roseau, le plus faible de la nature, mais c'est un roseau pensant. Il ne faut pas que l'univers entier s'arme pour l'écraser; une vapeur, une goutte d'eau suffit pour le tuer. Mais quand l'univers l'écraserait, l'homme serait encore plus noble que ce qui le tue, parce qu'il sait qu'il meurt et l'avantage que l'univers a sur lui; l'univers n'en sait rien."

(Original text quoted from "Cours Supérieur" AMSCO School Publications, 1970.)[edit] Regarding the Wager

For more information, see Pascal's Wager. "You must wager; it is not optional... Let us weigh the gain and the loss in wagering that God exists... If you gain, you gain all; if you lose, you lose nothing. Wager, then, without hesitation, that He exists.""Bless yourself with holy water, have Masses said, and so on; by a simple and natural process this will make you believe, and will dull you*—will quiet your proudly critical intellect."

* cela vous fera croire, et vous abêtira "Go to confession and communion; you will find it a relief and a strengthening."[edit] On Futility"Picture a number of men in chains, and all condemned to death; each day some are strangled in the sight of the rest; those who remain see their own condition in that of their fellows, looking at one another with sorrow and without hope, each awaiting his turn. This is the picture of the condition of man."[edit] The mystery of God"It is incomprehensible that God should exist, and it is incomprehensible that He should not exist; that the soul should be joined to the body, and that we should have no soul; that the world should be created, and that it should not be created, etc.; that original sin should be, and that it should not be.""We understand nothing of the works of God unless we take it as a principle that He wishes to blind some and to enlighten others.""This is what I see, and what troubles me. I look on all sides, and everywhere I see nothing but obscurity. Nature offers me nothing that is not a matter of doubt and disquiet. If I saw no signs of a divinity, I would fix myself in denial. If I saw everywhere the marks of a Creator, I would repose peacefully in faith. But seeing too much to deny [Him], and too little to assure me, I am in a pitiful state, and I would wish a hundred times that if a God sustains nature it would reveal Him without ambiguity."[edit] On the BibleIn Pensees' Section X "Typography", Pascal presents an unusual proof for a "double meaning" interpretation of The Bible.

642. Proof of the two Testaments at once.--To prove the two at one stroke, we need only see if the prophecies in one are fulfilled in the other. To examine the prophecies, we must understand them. For if we believe they have only one meaning, it is certain that the Messiah has not come; but if they have two meanings, it is certain that He has come in Jesus Christ. The whole problem then is to know if they have two meanings. That the Scripture has two meanings, which Jesus Christ and the Apostles have given, is shown by the following proofs: 1. Proof by Scripture itself.

2. Proof by the Rabbis. Moses Maimonides says that it has two aspects and that the prophets have prophesied Jesus Christ only. 3. Proof by the Kabbala. 4. Proof by the mystical interpretation which the Rabbis themselves give to Scripture. 5. Proof by the principles of the Rabbis, that there are two meanings; that there are two advents of the Messiah, a glorious and an humiliating one, according to their desert; that the prophets have prophesied of the Messiah only--the Law is not eternal, but must change at the coming of the Messiah--that then they shall no more remember the Red Sea; that the Jews and the Gentiles shall be mingled. 6. Proof by the key which Jesus Christ and the Apostles give us.

Pascal subsequently identifies the major problem of a "double meaning" reconciliation.648. Two errors: 1. To take everything literally. 2. To take everything spiritually.

In the fields of mathematics, computer science and information theory Pascal is widely regarded to be the "father of modern probability theory", the branch of science that underpins cryptography. Pascal's strangely disembodied conclusion to his closing argument for the "double meaning" divinity of the Bible, and his choice of the word "cipher", which was the technical word for "cryptogram" in its day, has been cited frequently in the context of "Bible codes", referring to information that is purported to be encrypted in the Torah of the Old Testament.

691. If one of two persons, who are telling silly stories, uses language with a double meaning, understood in his own circle, while the other uses it with only one meaning, any one not in the secret, who hears them both talk in this manner, will pass upon them the same judgment. But, if, afterwards, in the rest of their conversation one says angelic things, and the other always dull commonplaces, he will judge that the one spoke in mysteries, and not the other; the one having sufficiently shown that he is incapable of such foolishness and capable of being mysterious; and the other that he is incapable of mystery and capable of foolishness. The Old Testament is a cipher.

[edit] On atheists"Atheism shows strength of mind, but only to a certain degree."[edit] See also

Pascal's Wager

Wikisource has original text related to this article: Pensées[edit] Texts

Pascal's Pensees at Project Gutenberg Pascal's Pensees in French Etext of Pascal's Pensées (English, in various formats)

[edit] References1. ̂ Encyclopedia Britannica: Blaise Pascal (accessed 2008-03-14) 2. ̂ British Museum Catalogue of printed books: Pascal, Blaise, Thoughts on Religion, and other important

subjects. Newly translated from the French of Blaise Pascal. To which are added, Memoirs of his life and writings by the translator, Thomas Chevalier. London, 1803.

3. ̂ Dictionary of National Biography entry for Thomas Chevalier. 4. ̂ Jean Mesnard, French Wikipedia (translated) 5. ̂ See in particular various works by Laurent Thirouin, for example “Les premières liasses des Pensées :

architecture et signification”, XVIIe siècle, n°177 (spécial Pascal), oct./déc. 1992, pp. 451-468 or “Le cycle du divertissement, dans les liasses classées”, Giornata di Studi Francesi, “Les Pensées de Pascal : du dessein à l’édition”, Rome, Université LUMSA, 11-12 octobre 2002.

6. ̂ Pensees, Fragment 187, Edition Gallimard (1977) 7. ̂ Sainte-Beuve, Seventeenth Century, 174

Retrieved from "http://en.wikipedia.org/wiki/Pens%C3%A9es"

http://oce.catholic.com/index.php?title=Blaise_PascalBlaise PascalB. at Clermont-Ferrand, June 19, 1623; d. in Paris, August 19, 1662Published by Encyclopedia Press, 1913. Pascal, BLAISE, b. at Clermont-Ferrand, June 19, 1623; d. in Paris, August 19, 1662. He was the son of Etienne Pascal, advocate at the court of Aids of Clermont, and of Antoinette Bègon. His father, a man of fortune, went

with his children (1631) to live in Paris. He taught his son grammar, Latin, Spanish, and mathematics, all according to an original method. In his twelfth year Blaise composed a treatise on the communication of sounds; at sixteen another treatise, on conic sections. In 1639 he went to Rouen with his father, who had been appointed intendant of Normandy, and, to assist his father in his calculations, he invented the arithmetical machine. He repeated Torricelli's vacuum experiments and demonstrated, against Père Noël, the weight of air (cf. Mathieu, "Revue de Paris", 1906; Abel Lefranc, "Revue Bleue", 1906; Strowski, "Pascal", Paris, 1908). He published works on the arithmetical triangle, on wagers and the theory of probabilities, and on the roulette or cycloid. Meanwhile, in 1646, he had been won over to Jansenism, and induced his family, especially his sister Jacqueline, to follow in the same direction. In 1650, after a sojourn in Auvergne, his family returned to Paris. On the advice of physicians Pascal, who had always been ailing and who now suffered more than ever, relaxed his labors and mingled in society, with such friends as the Duc de Roannez, the Chevalier Méré, the poet Desbarreaux, the actor Miton. This was what has been called the worldly period of his life, during which he must have written the "Discours sur les passions de l'amour", inspired, it is said, by Mlle de Roannez. But the world soon became distasteful to him, and he felt more and more impelled to abandon it. During the night of November 23, 1654, his doubts were settled by a sort of vision, the evidence of which is in a writing, always subsequently carried in the lining of his coat, and called "Pascal's talisman". After this he practiced the most severe asceticism, renounced learning, and became the constant guest of Port Royal. In 1656 he undertook the defense of Jansenism, and published the "Provinciales". This polemical work was nearing completion when Pascal had the joy of seeing his friends, the Duc de Roannez and the jurisconsult Domat, converted to Jansenism, as well as his niece Marguerite Perier, who had been cured of a fistula of the eye by contact with a relic of the Holy Thorn preserved at Port Royal. Thenceforth, although exhausted by illness, Pascal gave himself more and more to God. He multiplied his mortifications, wore a cincture of nails which he drove into his flesh at the slightest thought of vanity, and to be more like Jesus crucified, he left his own house and went to die in that of his brother-in-law. He wrote the "Mystère de Jésus", a sublime memorial of his transports of faith and love, and he labored to collect the materials for a great apologetic work. He died at the age of thirty-nine, after having received in an ecstasy of joy the Holy Viaticum, for which he had several times asked, crying out as he half rose from his couch: "May God never abandon me!" Pascal left numerous scientific works, among which must be mentioned "Essai sur les coniques" (1640); "Avis à, ceux qui verront la machine arithmétique" (1645); "Récit de la grande experience de I'équilibre des liqueurs" (1648); "Traité du triangle arithmétique" (1654). He shows himself a determined advocate of the experimental method, in opposition to the mathematical and mechanical method of Descartes. In his "Traité sur la vide", often reprinted with the "Pensées" under the title "De l'autorité en matière de philosophic", Pascal clearly puts the question regarding progress, which he answers, boldly yet prudently, in "L'esprit géometrique", where he luminously distinguishes between the geometrical and the acute mind, and establishes the foundations of the art of persuasion. As to his authorship of the "Discours sur les passions de l'amour", that essay at least contains certain theories familiar to the author of the "Pensées" on the part played by intuition in sentiment and aesthetic, and its style for the most part resembles that of Pascal. The "Entretien avec M. de Saci sur Epictète et Montaigne" gives the key to the "Pensées"; psychology serving as the foundation and criterion of apologetics, various philosophies solving the problem only in one aspect, and Christianity alone affording the complete solution. But Pascal's two masterpieces are the "Provinciales" and the "Pensées". The occasion of the "Provinciales" was an accident. The Duc de Liancourt, a friend of Port Royal, having been refused absolution by the curé of Saint Sulpice. Antoine Arnauld wrote two letters which were censured by the Sorbonne. He wished to appeal to the public in a pamphlet which he submitted to his friends, but they found it too heavy and theological. He then said to Pascal: "You, who are young, must do something." The next day (January 23, 1656) Pascal brought the first "Provinciale". The "Petites lettres" followed to the number of nineteen, the last unfinished, from January, 1656, to March, 1657. Appearing under the pseudonym of Louis de Montalte, they were published at Cologne in 1657 as "Les Provinciales, ou Lettres écrites par Louis de Montalte à un provincial de ses amis et au RR. PP. Jésuites sur le sujet de la morale et de la politique de ces pères". The first four treat the dogmatic question which forms the basis of Jansenism on the agreement between grace and human liberty. Pascal answers it by practically, if not theoretically, denying sufficient grace and liberty. The seventeenth and eighteenth letters take up the same questions, but with noteworthy qualifications. From the fourth to the sixteenth Pascal censures the Jesuit moral code, or rather the casuistry, first, by depicting a naive Jesuit who, through silly vanity, reveals to him the pretended secrets of the Jesuit policy, and then by direct invective against the Jesuits themselves. The most famous are the fourth, on sins of ignorance, and the thirteenth, on homicide. That Pascal intended this to be a useful work; his whole life bears witness, as do his deathbed declarations. His good faith cannot seriously be doubted, but some of his methods are more questionable. Without ever seriously altering his citations from the casuists, as he has sometimes been wrongfully accused of doing, he arranges them somewhat disingenuously; he simplifies complicated questions excessively, and, in setting forth the solutions of the casuists sometimes lets his own bias interfere. But the gravest reproach against him is, first, that

he unjustly blamed the Society of Jesus, attacking it exclusively, and attributing to it a desire to lower the Christian ideal and to soften down the moral code in the interest of its policy; then that he discredited casuistry itself by refusing to recognize its legitimacy or, in certain cases, its necessity, so that not only the Jesuits, but religion itself suffered by this strife, which contributed to hasten the condemnation of certain lax theories by the Church. And, without wishing or even knowing it, Pascal furnished weapons on the one hand to unbelievers and adversaries of the Church and on the other to the partisans of independent morality. As to their literary form, the "Provinciales" are, in point of time, the first prose masterpiece of the French language, in their satirical humor and passionate eloquence. The "Pensées" are an unfinished work. From his conversion to Jansenism Pascal nourished the project of writing an apology for the Christian Religion which the increasing number of libertines rendered so necessary at that time. He had elaborated the plan, and at intervals during his illness he jotted down notes, fragments, and meditations for his book. In 1670 Port Royal issued an incomplete edition. Condorcet, on the advice of Voltaire, attempted, in 1776, to connect Pascal with the Philosophic party by means of a garbled edition, which was opposed by that of the Abbé Bossuet (1779). After a famous report of Cousin on the MS. of the "Pensées" (1842), Faugère published the first critical edition (1844), followed since then by a host of others, the best of which is undoubtedly that of Michaut (Basle, 1896), which reproduces the original MS. pure and simple. What Pascal's plan was, can never be determined, despite the information furnished by Port Royal and by his sister. It is certain that his method of apologetics must have been at once rigorous and original; no doubt, he had made use of the traditional proofs—notably, the historical argument from prophecies and miracles. But as against adversaries who did not admit historical certainty, it was a stroke of genius to produce a wholly psychological argument and, by starting from the study of the human soul, to arrive at God. Man is an "incomprehensible monster", says he, "at once sovereign greatness and sovereign misery." Neither dogmatism nor pyrrhonism will solve this enigma: the one explains the greatness of man, the other his misery; but neither explains both. We must listen to God. Christianity alone, through the doctrine of the Fall and that of the Incarnation, gives the key to the mystery. Christianity, therefore, is truth. God being thus apprehended and felt by the heart—which "has its reasons that the mind knows not of", and which, amid the confusion of the other faculties, is never mistaken—it remains for us to go to Him through the will, by making acts of faith even before we have faith. Another curious argument of Pascal's is that which is known as the argument of the wager. God exists or He does not exist, and we must of necessity lay odds for or against Him. If I wager for, and God is—infinite gain; and God is not—no loss. If I wager against, and God is—infinite loss; and God is not—neither loss nor gain. In the second case there is an hypothesis wherein I am exposed to the loss of everything. Wisdom, therefore, counsels me to make the wager which insures my winning all or, at worst losing nothing. Innumerable works were devoted to Pascal in the second half of the nineteenth century. Poets, critics, romance-writers, theologians, philosophers have drawn their inspiration from him or made him the subject of discussion. As M. Bourget has said, he is not only one of the princes of style, but he represents the religious soul in its most tragic and terrified aspects. Moreover, the problems which he presents are precisely those which confront us nowadays. J. LATASTE Retrieved from "http://oce.catholic.com/index.php?title=Blaise_Pascal"

http://www.newadvent.org/cathen/11511a.htmBlaise PascalBorn at Clermont-Ferrand, 19 June 1623; died in Paris, 19 August 1662. He was the son of Etienne Pascal, advocate at the court of Aids of Clermont, and of Antoinette Bégon. His father, a man of fortune, went with his children (1631) to live in Paris. He taught his son grammar, Latin, Spanish, and mathematics, all according to an original method. In his twelfth year Blaise composed a treatise on the communication of sounds; at sixteen another treatise, on conic sections. In 1639 he went to Rouen with his father, who had been appointed intendant of Normandy, and, to assist his father in his calculations, he invented the arithmetical machine. He repeated Torricelli's vacuum experiments and demonstrated, against Père Noël, the weight of air (cf. Mathiew, "Revuede Paris", 1906; Abel Lefranc "Revue Bleue", 1906; Strowski, "Pascal", Paris, 1908). He published works on the arithmetical triangle, on wagers and the theory of probabilities, and on the roulette or cycloid. Meanwhile, in 1646, he had been won over to Jansenism, and induced his family, especially his sister Jacqueline, to follow in the same direction. In 1650, after a sojourn in Auvergne, his family returned to Paris. On the advice of physicians Pascal, who had always been ailing and who now suffered more than ever, relaxed his labours and mingled in society, with such friends as the Duc de Roannez, the Chevalier Mere, the poet Desbarreaux, the actor Milton. This was what has been called the worldly period of his life, during which he must have written the "Discours sur les passions de l'amour", inspired, it is said, by Mlle de Roannez. But the world

soon became distasteful to him, and he felt more and more impelled to abandon it. During the night of 23 November 1654, his doubts were settled by a sort of vision, the evidence of which is in a writing, always subsequently carried in the lining of his coat, and called "Pascal's talisman". After this he practiced the most severe asceticism, renounced learning, and became the constant guest of Port Royal. In 1656 he undertook the defense of Jansenism, and published the "Provinciales". This polemical work was nearing completion when Pascal had the joy of seeing his friends, the Duc de Roannez and the jurisconsult Domat, converted to Jansenism, as well as his niece Marguerite Perier, who had been cured of a fistula of the eye by contact with a relic of the Holy Thorn preserved at Port Royal. Thenceforth, although exhausted by illness, Pascal gave himself more and more to God. He multiplied his mortifications, wore a cincture of nails which he drove into his flesh at the slightest thought of vanity, and to be more like Jesus crucified, he left his own house and went to die in that of his brother-in-law. He wrote the "Mystère de Jesus", a sublime memorial of his transports of faith and love, and he laboured to collect the materials for a great apologetic work. He died at the age of thirty-nine, after having received in an ecstasy of joy the Holy Viaticum, for which he had several times asked, crying out as he half rose from his couch: "May God never abandon me!" Pascal left numerous scientific works, among which must be mentioned "Essai sur les coniques" (1640); "Avis à ceux qui verront la machine arithmétique" (1645); "Récit de la grande expérience de l'équilibre des liqueurs" (1648); "Traité du triangle arithmétique" (1654). He shows himself a determined advocate of the experimental method, in opposition to the mathematical and mechanical method of Descartes. In his "Traité sur la vide", often reprinted with the "Pensées" under the title "De l'autorité en matière de philosophie", Pascal clearly puts the question regarding progress, which he answers, boldly yet prudently in "L'esprit géometrique", where he luminously distinguishes between the geometrical and the acute mind, and establishes the foundations of the art of persuasion. As to his authorship of the "Discours sur les passions de l'amour", that essay at least contains certain theories familiar to the author of the "Pensées" on the part played by intuition in sentiment and æsthetic, and its style for the most part resembles that of Pascal. The "Entretien avec M. de Saci sur Epictète et Montaigne" gives the key to the "Pensées"; psychology serving as the foundation and criterion of apologetics, various philosophies solving the problem only in one aspect, and Christianity alone affording the complete solution. But Pascal's two masterpieces are the "Provinciales" and the "Pensées". The occasion of the "Provinciales" was an accident. The Duc of Liancourt, a friend of Port Royal, having been refused absolution by the curé of Saint Sulpice, Antoine* Arnauld wrote two letters which were censured by the Sorbonne. He wished to appeal to the public in a pamphlet which he submitted to his friends, but they found it too heavy and theological. He then said to Pascal: "You, who are young, must do something." The next day (23 Jan., 1656) Pascal brought the first "Provinciale". The "Petites lettres" followed to the number of nineteen, the last unfinished, from January, 1656, to March, 1657. Appearing under the pseudonym of Louis de Montalte, they were published at Cologne in 1657 as Les Provinciales, ou Lettres écrites par Louis de Montalte à un provincial de ses amis et au RR. PP. Jesuites sur le sujet de la morale et de la politique de ces pères". The first four treat the dogmatic question which forms the basis of Jansenism on the agreement between grace and human liberty. Pascal answers it by practically, if not theoretically, denying sufficient grace and liberty. The seventeenth and eighteenth letters take up the same questions, but with noteworthy qualifications. From the fourth to the sixteenth Pascal censures the Jesuit moral code, or rather the casuistry, first, by depicting a naîf Jesuit who, through silly vanity, reveals to him the pretended secrets of the Jesuit policy, and then by direct invective against the Jesuits themselves. The most famous are the fourth, on sins of ignorance, and the thirteenth, on homicide. That Pascal intended this to be a useful work, his whole life bears witness, as do his deathbed declarations. His good faith cannot seriously be doubted, but some of his methods are more questionable. Without ever seriously altering his citations from the casuists, as he has sometimes been wrongfully accused of doing, he arranges them somewhat disingenously; he simplifies complicated questions excessively, and, in setting forth the solutions of the casuists sometimes lets his own bias interfere. But the gravest reproach against him is, first, that he unjustly blamed the Society of Jesus, attacking it exclusively, and attributing to it a desire to lower the Christian ideal and to soften down the moral code in the interest of its policy; then that he discredited casuistry itself by refusing to recognize its legitimacy or, in certain cases, its necessity, so that not only the Jesuits, but religion itself suffered by this strife, which contributed to hasten the condemnation of certain lax theories by the Church. And, without wishing or even knowing it, Pascal furnished weapons on the one hand to unbelievers and adversaries of the Church and on the other to the partisans of independent morality. As to their literary form, the "Provinciales" are, in point of time, the first prose masterpiece of the French language, in their satirical humour and passionate eloquence. The "Pensées" are an unfinished work. From his conversion to Jansenism Pascal nourished the project of writing an apology for the Christian Religion which the increasing number of libertines rendered so necessary at that time. He had elaborated the plan, and at intervals during his illness he jotted down notes, fragments, and meditations for his book. In 1670 Port Royal issued an incomplete edition. Condorcet, on the advice of Voltaire, attempted, in 1776, to connect Pascal with the Philosophie party by means of a garbled edition, which was

opposed by that of the Abbé Bossuet (1779). After a famous report of Cousin on the manuscript of the "Pensées" (1842), Faugère published the first critical edition (1844), followed since then by a host of others, the best of which is undoubtedly that of Michaut (Basle, 1896), which reproduces the original manuscript pure and simple. What Pascal's plan was, can never be determined, despite the information furnished by Port Royal and by his sister. It is certain that his method of apologetics must have been at once rigorous and original; no doubt, he had made use of the traditional proofs -- notably, the historical argument from prophecies and miracles. But as against adversaries who did not admit historical certainty, it was stroke of genius to produce a wholly psychological argument and, by starting from the study of the human soul , to arrive at God. Man is an "incomprehensible monster", says he, "at once sovereign greatness and sovereign misery." Neither dogmatism nor pyrrhonism will solve the enigma: the one explains the greatness of man, the other his misery; but neither explains both. We must listen to God. Christianity alone, through the doctrine of the Fall and that of the Incarnation, gives the key to the mystery. Christianity, therefore, is truth. God being thus apprehended and felt by the heart -- which "has its reasons that the mind knows not of", and which, amid the confusion of the other faculties, is never mistaken -- it remains for us to go to Him through the will, by making acts of faith even before we have faith. Another curious argument of Pascal's is that which is known as the argument of the wager. God exists or He does not exist, and we must of necessity lay odds for or against Him.

If I wager for and God is -- infinite gain; If I wager for and God is not -- no loss. If I wager against and God is -- infinite loss; If I wager against and God is not -- neither loss nor gain.

In the second case there is an hypothesis wherein I am exposed to the loss of everything. Wisdom, therefore, counsels me to make the wager which insures my winning all or, at worst losing nothing. Innumerable works were devoted to Pascal in the second half of the nineteenth century. Poets, critics, roman-writers, theologians, philosophers have drawn their inspiration from him or made him the subject of discussion. As M. Bourget has said, he is not only one of the princes of style, but he represents the religious soul in its most tragic and terrified aspects. Moreover, the problems which he presents are precisely those which confront us nowadays. SourcesSAINT-BEUVE, Port-Royal, I, II, III (Paris, 1880); VINET, Etude sur Blaise Pascal (Paris, 1848); SULLY-PRUDHOMME, La vraie religion selon Pascal (Paris, 1909); BRUNETIERE, Etudes critiques, ser. 1, 3, 4; Hist. et literature, II (Paris, 1880-1903); MICHAUT, Les époques de la pensée de Pascal (Paris, 1897); GIRAUD, Pascal; l'homme, l'oeuvre, l'influence (Paris, 1905); BOUTROUX in Coll. des grands écrivains francais (Paris, 1900); STROWSKI, Pascal et son temps (Paris, 1909); (especially important); TAYLOR, Pascal's Thoughts on Religion and Philosophy (London, 1804); JANNESS, La philosophie et l'apologétique de P. (Louvain, 1896).

http://fr.wikipedia.org/wiki/Blaise_PascalBlaise PascalBlaise Pascal (19 juin 1623, Clermont-Ferrand, Auvergne - 19 août 1662, Paris) est un mathématicien et physicien, philosophe, moraliste et théologien français.Enfant précoce, il est éduqué par son père. Les tout premiers travaux de Pascal concernent les sciences naturelles et appliquées. Il contribue de manière importante à la construction d’une calculatrice mécanique (la « Pascaline ») et à l’étude des fluides. Il a clarifié les concepts de pression et de vide, en étendant le travail de Torricelli. Pascal a écrit des textes importants sur la méthode scientifique.Mathématicien de premier ordre, il crée deux nouveaux champs de recherche majeurs : tout d’abord il publie un traité de géométrie projective à seize ans ; ensuite il correspond, à partir de 1654, avec Pierre de Fermat à propos de la théorie des probabilités, qui influencera fortement les théories économiques modernes et les sciences sociales.Après une expérience mystique à la fin de 1654, il délaisse les mathématiques et la physique et se consacre à la réflexion philosophique et religieuse. Il écrit pendant cette période les Provinciales et les Pensées, ces dernières n’étant publiées qu’après sa mort qui survient deux mois après son 39e anniversaire, alors qu’il a été malade toute sa vie (sujet à des migraines violentes en particulier).

Sommaire[masquer]

1 Biographie o 1.1 Conversion religieuse o 1.2 Derniers travaux et mort

2 Contributions aux mathématiques 3 Philosophie des mathématiques

o 3.1 Axiomatique o 3.2 Pédagogie

4 Contributions aux sciences physiques o 4.1 Expérience des liqueurs

5 Religion, philosophie, et littérature de la maturité o 5.1 Les Provinciales o 5.2 Miracle o 5.3 Pensées

6 Postérité 7 Liste des principales œuvres 8 Citation 9 Références

o 9.1 Notes o 9.2 Textes de Pascal o 9.3 Sur Pascal

10 Voir aussi o 10.1 Articles connexes

10.1.1 Travaux de Blaise Pascal 10.1.2 Contemporains 10.1.3 Références posthumes

o 10.2 Liens externes

Biographie [modifier]Né à Clermont, en Auvergne, Blaise Pascal perd sa mère, Antoinette Bégon, à l’âge de trois ans. Son père, Étienne Pascal (1588-1651) très intéressé par les mathématiques et les sciences, était un juge local et membre de la petite noblesse. Blaise Pascal avait deux sœurs, Jacqueline, née en 1625, et Gilberte (née en 1620, mariée en 1641 à Florin Périer) qui lui survécut.En 1631, Étienne se rend avec ses enfants à Paris. Il décide d’éduquer lui-même son fils qui montrait des dispositions mentales et intellectuelles extraordinaires. En effet très tôt, Blaise a une capacité immédiate pour les mathématiques et la science, peut-être inspiré par les conversations fréquentes de son père avec les principaux savants de l’époque : Roberval, Mersenne, Desargues, Mydorge, Gassendi et Descartes.À onze ans, il compose un court Traité des sons des corps vibrants et démontre la 32e proposition du Ier livre d’Euclide. Étienne réagit en interdisant à son fils toute poursuite de ses études en mathématiques jusqu’à quinze ans, afin qu’il puisse étudier le latin et le grec. Sainte-Beuve (dans son Port-Royal, III, p. 484) raconte :« Je n’ai rien à dire des éléments de géométrie, si ce n’est que Pascal, qui les avait lus en manuscrit, les jugea si clairs et si bien ordonnés, qu’il jeta au feu, dit-on, un essai d’éléments qu’il avait fait lui-même d’après Euclide, et qu’Arnauld avait jugé confus ; c’est même ce qui avait d’abord donné à Arnauld l’idée de composer son essai : Pascal le défia en riant de faire mieux, et le docteur, à son premier loisir, tint et gagna la gageure. »À douze ans (1635), il commence à travailler seul sur la géométrie et découvre que la somme des angles d’un triangle est égale à 180°.Le travail de Desargues intéressa particulièrement le jeune Pascal et lui inspira, à seize ans, un traité sur les sections coniques : Essai sur les coniques. La majeure partie en est perdue mais un résultat essentiel et original en reste sous le nom de théorème de Pascal. Le travail de Pascal était si précoce que Descartes, quand il a vu le manuscrit, croyait qu’il était de son père.En 1638, Étienne, opposé aux dispositions fiscales du Cardinal de Richelieu, quitte Paris avec sa famille pour échapper à la Bastille. Lorsque Jacqueline, sœur de Blaise, dit un compliment particulièrement bien tourné devant Richelieu, Étienne obtient sa grâce. En 1639, la famille s’installe à Rouen où Étienne devient commissaire délégué par le Roi pour l’impôt et la levée des tailles.À dix-huit ans (1641), Pascal construit la Pascaline, machine à calculer capable d’effectuer des additions et des soustractions afin d’aider son père dans son travail. Il en écrit le mode d’emploi : Avis nécessaire à ceux qui auront la curiosité de voir ladite machine et s’en servir. Plusieurs exemplaires sont conservés, en France, au Musée des Arts et Métiers à Paris et au musée de Clermont-Ferrand. Bien que ce soit le tout début du calcul

mécanique, ce fut un échec commercial à cause de son coût élevé (100 livres). Pascal améliorera la conception de la machine pendant encore dix années et en construira une cinquantaine d’exemplaires.Conversion religieuse [modifier]D’un point de vue biographique, deux influences de base le guident vers sa conversion : le jansénisme et la maladie.En 1646, le père de Pascal s’est démis la cuisse en tombant sur la glace, il est soigné par deux médecins jansénistes (La Bouteillerie et Deslandes), disciples de Jean Duvergier de Hauranne (abbé de Saint-Cyran) qui introduisit le jansénisme en France. Blaise parle fréquemment avec eux durant les trois mois du traitement de son père, il leur emprunte des livres d’auteurs jansénistes, en particulier enthousiasmé par le Discours de la réformation de l'homme intérieur écrit par Cornelius Jansen en 1628, dont il ressort si vivement marqué qu'il communique son admiration à ses proches, certains affirmant donc que ce fut là la date de sa "première conversion".Il découvre que marcher sur les traces de Copernic et de Galilée pour libérer la physique du poids mort d’Aristote et de la scolastique n’est que la démarche d’une vaine raison, impliquée dans la souillure de l’humanité toute entière, et que tout ce génie qui bouillonne en lui ne le conduit qu’à le divertir d’une révélation terrible et rédemptrice. Que signifie un savoir qui ne jette pas l’homme au pied de la Croix ? Dans cette période, Pascal vit une sorte de « première conversion » et commence, au cours de cette année, d’écrire sur des sujets théologiques. Toute sa famille se met à « goûter Dieu » avec lui.Dès sa dix-huitième année, il subit un mal nerveux qui le laisse rarement un jour sans souffrance. En 1647, une attaque de paralysie l’atteint au point qu’il ne peut plus se mouvoir sans béquilles. Il a mal à la tête, des maux de ventre, ses jambes et ses pieds sont continuellement froids et demandent des soins pour activer la circulation sanguine ; il porte des bas trempés dans de l’eau-de-vie pour se réchauffer les pieds. En partie pour avoir de meilleurs traitements médicaux, il se rend à Paris avec sa sœur Jacqueline. Sa santé s’améliore mais son système nerveux est perturbé de manière permanente. Dorénavant, il est sujet à une profonde hypocondrie, qui a affecté son caractère et sa philosophie. Il est devenu irritable, sujet à des accès de colère fière et impérieuse, et il sourit rarement.Pascal s’éloigne de son premier engagement religieux et il vit pendant quelques années ce qu’il a appelé « une période mondaine » (1648-1654). Ce sont les expériences sur le vide, à la suite des travaux de Torricelli, qui l'occupent pleinement. De 1646 à 1654, il multiplie les expérimentations avec toutes sortes d’instruments. L’une d’entre elles, en 1648 lui permet de confirmer la réalité du vide et de la pression atmosphérique et d’établir la théorie générale de l’équilibre des liquides.Son père meurt en 1651 et Pascal prend possession de son héritage et de celui de sa sœur Jacqueline. Cette même année, Jacqueline entre à l'abbaye de Port-Royal de Paris, en dépit de l’opposition de son frère. Quand le temps vient pour elle de prononcer ses vœux définitifs, il refuse de lui rendre une part de son héritage pour payer sa dot de nonne ; sans argent elle aura une position moins élevée dans la hiérarchie du couvent. Ce n’est qu’en 1653 qu’il acceptera de lui constituer une dot, au moment où une bulle d’Innocent X condamne cinq propositions de Jansénius.Ainsi, Pascal se trouve à la fois riche et libre. Il prend une maison somptueusement meublée, avec beaucoup de domestiques et se fait conduire dans Paris avec une voiture tirée par quatre ou six chevaux. Il passe son temps en compagnie de beaux esprits, de femmes et de joueurs (comme son travail sur les probabilités le montre). Il poursuit un temps, en Auvergne, ses travaux et une dame de grande beauté, qu’il appelle la « Sapho de la campagne ». À cette époque, il inspire un Discours sur les passions de l’amour (qui ne semble pas être de sa main), et apparemment il a médité sur le mariage qu’il décrit plus tard comme « la plus basse des conditions de la vie permises à un chrétien  ».Jacqueline lui reproche sa frivolité et prie pour qu’il change de vie. Durant les visites à sa sœur à Port-Royal en 1654, il montre du mépris pour les affaires du monde mais il n’est pas attiré par Dieu.À la fin de 1654, il a un accident sur le pont de Neuilly où les chevaux plongent par-dessus le parapet et la voiture est près de les suivre. Heureusement, l’attelage se rompt et la voiture reste en équilibre sur le bord du pont. Pascal et ses amis sortent, mais le philosophe hypersensible, terrifié par la proximité de la mort, s’évanouit et reste inconscient. Revenant à lui quinze jours plus tard, le 23 novembre 1654, entre dix heures et demi et minuit et demie, Pascal a une intense vision religieuse qu’il écrit immédiatement pour lui-même en une note brève, appelé le Mémorial en littérature, commençant par : « Feu. Dieu d’Abraham, Dieu d’Isaac, Dieu de Jacob, pas des philosophes ni des savants… » et qu’il conclut par une citation du Psaume 119,16 : « Je n’oublierai pas ces mots. Amen. » Il coud soigneusement ce document dans son manteau et le transfère toujours quand il change de vêtement ; un serviteur le découvrira par hasard après sa mort. Pendant sa vie, Pascal a souvent été considéré par erreur comme un libertin et, plus tard, il a été tenu à l’écart comme une personne n’ayant eu une conversion que sur son lit de mort. Sa croyance et son engagement religieux réactivés, Pascal loge dans le plus ancien des deux couvents de Port-Royal pour une retraite de quinze jours en janvier 1655. Pendant les quatre années suivantes, il fit régulièrement le voyage entre Paris et Port-Royal-des-Champs. Il commence à écrire, immédiatement après sa conversion, son œuvre majeure sur la religion, Les Provinciales.

Pascal participa aux travaux de traduction en français de la Bible, en utilisant les principes de la Logique de Port-Royal.Pascal est également à l’origine de l’invention de la presse hydraulique, basé sur le principe qui porte son nom.On lui doit également l’invention du haquet, véhicule hippomobile conçu pour le transport des marchandises en tonneaux.Derniers travaux et mort [modifier]Thomas Stearns Eliot décrit Pascal, à cette période de sa vie, comme « un homme mondain parmi les ascètes et comme un ascète parmi les hommes du monde ». Le style de vie ascétique de Pascal venait de sa foi en ce qu'il était naturel et normal pour un homme de souffrir. Dans ces dernières années troublées par une mauvaise santé, il rejette les ordonnances de ses médecins en disant : « La maladie est l'état naturel du chrétien. » D'après sa sœur Gilberte, il aurait écrit alors sa Prière pour demander à Dieu le bon usage des maladies.En 1659, Pascal, dont la santé n'a jamais été bonne, tombe sérieusement malade.Louis XIV a interdit le mouvement janséniste de Port-Royal en 1661. En réponse, Pascal a écrit un de ses derniers travaux, Écrit sur la signature du formulaire, recommandant instamment aux jansénistes de ne pas le signer. Plus tard au cours de cette année, sa sœur Jacqueline est morte, ce qui a convaincu Pascal de cesser sa polémique à propos du jansénisme.Grâce à ses connaissances en hydrostatique, il participe à l’assèchement des marais poitevins, à la demande du Duc de Roannez. C'est avec ce dernier qu'il inaugurera la dernière de ses réalisations qui reflète parfaitement le souci d’action concrète qui habite le savant : la première ligne de "transports en commun", convoyant les passagers dans Paris avec « des carrosses à cinq sols » munis de plusieurs sièges.En 1662, la maladie de Pascal est devenue plus violente. Conscient du fait qu'il a peu de chances de survivre, il songe à trouver un hôpital pour les maladies incurables, mais ses médecins le déclarent intransportable. À Paris, le 17 août 1662, Pascal a des convulsions et reçoit l’extrême onction. Il est mort le matin du 19 au n°8 de la rue Neuve-Saint-Étienne-du-Mont (devenue le n°2 de la rue Rollin), ses derniers mots étant « Puisse Dieu ne jamais m'abandonner ». Il est enterré dans l'église Saint-Étienne-du-Mont.L'autopsie pratiquée après sa mort révélera de graves problèmes stomacaux et abdominaux, accompagnés de lésions cérébrales. Malgré cette autopsie, la raison exacte de sa santé chancelante n'est pas connue.Des spéculations ont eu lieu à propos de tuberculose, d'un cancer de l'estomac ou d'une combinaison des deux. Les maux de tête qui affectaient Pascal sont attribués à la lésion cérébrale. (Marguerite Périer, sa nièce dit dans sa biographie de Pascal que l'autopsie révéla que « le crâne ne comportait aucune trace de suture autre que la lambdoïde… avec une abondance de cervelle, dont la substance était si solide et si condensée… »).Les professeurs M. Dordain et R. Dailly de la Faculté de Médecine de Rouen développent, dans les années 1970, les travaux de MM. Augeix, Chedecal, Crussaire et Nautiacq et établissent un «diagnostic d’insuffisance rénale chronique» avec «suspicion d’une maladie polykistique des reins» et «présence de lésions vasculaires cérébrales en voie de complications (thrombose)». Pascal aurait donc été atteint «d’une maladie génétique… (dont) les expressions cliniques (entrent) dans le cadre des dystrophies angioplasiques congénitales… objet de travaux (Pr J.-M. Cormier et Dr J.-M. André) ces dernières années»1.Contributions aux mathématiques [modifier]

Le triangle de PascalToute sa vie, Pascal contribue aux mathématiques par des travaux majeurs. Dès l'âge de seize ans, il commence à travailler sur ce qui deviendra plus tard la géométrie projective. Il utilise et approfondit les travaux du Brouillon-project d'une atteinte aux evenemens des rencontres du cone avec un plan de Girard Desargues ainsi que ceux d'Apollonius. Ainsi, en 1640, il fait imprimer son Essai pour les coniques et achève, en 1648, un traité de la Generatio conisectionum (Génération des sections coniques), dont il ne reste que des extraits pris par Leibniz. La grande innovation est le théorème de Pascal qui dit que l’hexagramme formé par 6 points d’une conique a ses côtés opposés concourants en trois points alignés.A partir de 1650, Pascal s’intéresse au calcul infinitésimal et, en arithmétique, aux suites de nombres entiers. Il énonce pour la première fois le principe du raisonnement par récurrence.En 1654, il écrit son Traité du triangle arithmétique dans lequel il donne une présentation commode en tableau des coefficients du binôme, le « triangle arithmétique », maintenant connu sous le nom de « triangle de Pascal » (un mathématicien chinois sous la dynastie Qin, Yang Hui, avait travaillé quatre siècles plus tôt sur un concept semblable au triangle de Pascal et Omar Khayyam, six siècles plus tôt).La même année, un ami, intéressé par les problèmes de jeu, l’interroge, Pascal correspond avec Fermat sur le sujet et de cette collaboration va naître la théorie mathématique des probabilités. Son ami était le Chevalier de

Méré et le problème était celui dit de la « règle des partis » : deux joueurs décident d’arrêter de jouer avant la fin du jeu et souhaitent partager les gains de manière équitable en s’appuyant sur les chances que chacun avait de gagner parvenu à ce point. C’était l’introduction de la notion d ’« espérance mathématique ». Pascal, plus tard dans les Pensées utilisera un argument probabiliste, le « pari de Pascal », pour justifier de sa croyance en Dieu et en une vie vertueuse. Le travail fait par Pascal et Fermat dans le calcul des probabilités constitue une importante préparation du travail de Leibniz sur le calcul infinitésimal.Ses derniers travaux scientifiques concernent les cycloïdes. En 1658, il résout ainsi certains problèmes qui occupaient nombre de mathématiciens, liés notamment à l’aire et au volume créés par la rotation d’une cycloïde autour de son axe.Après l’expérience mystique de 1654, Pascal abandonne presque complètement tout travail de mathématique. Cependant, après une nuit d’insomnie en 1658, il offre anonymement un prix pour la résolution de la quadrature de la cycloïde. Des solutions sont proposées par Wallis, Huygens, Wren et d’autres ; Pascal, toujours sous un pseudonyme, publie alors sa propre solution Histoire de la roulette (en français et en latin) avec une Suite de l’histoire de la roulette à la fin de l’année. En 1659, il envoie à Huygens une Lettre sur la dimension des lignes courbes sous le nom de Dettonville.

« Had Pascal confined his attention to mathematics he might have enriched the subject with many remarquable discoveries. But after his early youth he devoted most of his small measure of strength to theological questions 2. ».

(Si Pascal avait concentré ses efforts sur les mathématiques, il aurait pu enrichir le sujet avec de remarquables découvertes. Mais, passée sa jeunesse, il employa la plus grande partie de ses faibles capacités à des questions théologiques).Philosophie des mathématiques [modifier]Axiomatique [modifier]La contribution majeure de Pascal à la philosophie des mathématiques est De l’Esprit géométrique, écrit originellement comme une préface d’un manuel Éléments de géométrie pour les célèbres petites-écoles de Port-Royal, à la demande d’Arnauld. Ce travail n’a été publié qu’un siècle après sa mort. Pascal y examine les possibilités de découvrir la vérité, argumentant que l’idéal pour une semblable méthode serait de se fonder sur les propositions dont la vérité est déjà établie. Toutefois, il affirmait que c’était impossible parce que pour établir ces vérités, il faudrait s’appuyer sur d’autres vérités et que les principes premiers ne pourraient être atteints. De ce point de vue, Pascal affirmait que la procédure utilisée en géométrie était aussi parfaite que possible, avec certains principes énoncés mais non démontrés et les autres propositions étant développées à partir d’eux. Néanmoins, il n’existait pas de possibilité de savoir si ces principes étaient vrais.Dans De l’Esprit géométrique et de l’Art de persuader, Pascal étudie plus encore la méthode axiomatique en géométrie, particulièrement la question de savoir comment le peuple peut être convaincu par les axiomes sur lesquels les conclusions sont fondées ensuite. Pascal est d’accord avec Montaigne qu’obtenir la certitude à propos de ces axiomes et des conclusions grâce aux méthodes humaines était impossible. Il assurait que ces principes ne pouvaient être saisis que par l’intuition et que ce fait soulignait la nécessité de la soumission à Dieu dans la recherche de la vérité.Pascal développe aussi dans De l’Esprit géométrique… une théorie de la définition. Il distingue les définitions qui sont des termes conventionnels définis par l’auteur et les définitions incluses dans le langage et comprises par tous parce qu’elles désignent naturellement leur référent. Les secondes sont caractéristiques de la philosophie de l’essence (essentialisme). Pascal affirme que seules les définitions du premier type sont importantes pour la science et les mathématiques, considérant que ces domaines devraient adopter la philosophie du formalisme, comme Descartes l’a établie.Pédagogie [modifier]Pascal montre dans ces Éléments de géométrie tout son intérêt pour l’enseignement et ses réflexions à propos de la pédagogie des mathématiques et aussi dans un autre fragment, connu par l’intermédiaire de Leibniz, sur une méthode de lecture qu’il a discuté avec sa sœur Jacqueline, chargée d’enseigner dans les petites-écoles de Port-Royal. Il a semble-t-il lui-même enseigné, chez lui, à plusieurs enfants « en loques » (d’après Villandry). Dans cette méthode de lecture, qu’il présente comme Une nouvelle manière pour apprendre à lire facilement en toutes sortes de langues, il recommande :

« Cette méthode regarde principalement ceux qui ne savent pas encore lire. (...) chaque lettre ayant son nom, on la prononce seule autrement qu’en l’assemblant avec d’autres. (...) Il semble que la voie la plus naturelle (...) est que ceux qui montrent à lire, n’apprissent d’abord aux enfants à connaître les lettres, que par le nom de leur prononciation. »

Pascal donne des indications sur l’ordre de présentation des lettres et des divers cas avec ou sans diphtongue, etc.

« Et ensuite on leur apprendrait à prononcer à part, et sans épeler, les syllabes ce, ci, ge, gi, tia, tie, tii... »

Contributions aux sciences physiques [modifier]Expérience des liqueurs [modifier]Blaise Pascal a également réalisé la fameuse expérience des liqueurs (qu’on traduirait aujourd’hui par Expérience des liquides), qui prouva qu’il existait une « pression atmosphérique ». À l’époque, (où la science était encore très liée à la scolastique et à Église) l’idée était courante selon laquelle « la nature a horreur du vide ». La plupart des scientifiques supposaient que quelque invisible matière remplissait cet espace, mais que ce n’était pas un espace vide. Des inondations ayant eu lieu en Italie et en Hollande avaient conduit à des pompages d’eau pour vider les carrières de minerai des deux pays. Mais les pompes énormes fabriquées pour l’occasion laissaient perplexes les hommes de l’Église : la hauteur de l’eau dans les tubes de pompage s’arrêtait à 10,33 m. Et cela en des lieux très différents. À Clermont, Blaise Pascal est en train d’écrire un traité sur la mécanique des fluides. Il émet donc l’hypothèse qu’une sorte de « pression atmosphérique » empêche l’eau de monter très haut dans les pompes, et que le vide occupe l’espace supérieur des tubes. Cependant, il se heurte fortement à certains esprits de son temps et particulièrement à l'Église, qui fait refaire l’étanchéité des pompes afin de vérifier qu’il ne s’agit pas d’air. Mais leurs travaux leur donnent finalement tort.Blaise Pascal répète, en 1646 avec son père à Rouen, les expériences de Torricelli sur le vide. Un procès verbal en est envoyé à leur ami Chanut (ambassadeur du Roi en Suède). En 1647, Pascal publie ses Expériences nouvelles touchant le vide et une préface pour un Traité du Vide (voir aussi vide dans le vide), où il détaille les règles de base décrivant à quel degré les divers liquides pouvaient être maintenus par la pression de l’air. Il fournit aussi les raisons pour lesquelles un vide se trouvait réellement au-dessus de la colonne de liquide dans le tube barométrique.Il a alors l’idée d’une expérience qu’il va réaliser le 19 septembre 1648 : la pression atmosphérique devrait être différente en ville (à Clermont) et en haut de la montagne la plus proche, le Puy de Dôme, où la pression doit être inférieure à la pression régnant au niveau de la ville. Pascal fait donc transporter par son beau-frère, Florin Périer, un tube de Torricelli en haut du Puy-de-Dôme. Des curés et des savants suivent l’expérience. Grâce au tube-témoin en ville, la présence de vide est démontrée. Il publie le Récit de la grande expérience de l’équilibre des liqueurs.Ce travail de recherche se termine en 1651 par un Traité du vide (seuls des fragments en sont connus) et sa réduction par Pascal en deux traités de l’Équilibre des liqueurs et de la Pesanteur de l’air. C’est en septembre de cette année que son père Étienne meurt.Le travail de Pascal dans l’étude des fluides (hydrodynamique et hydrostatique) est centré sur les principes des fluides hydrauliques. Il invente la presse hydraulique (utilisant la pression hydraulique pour multiplier la force) et la seringue.Face aux critiques qui soutenaient que quelque matière invisible existait dans l’espace vide de Pascal, Pascal a répondu à Étienne Noël un des principaux fondateurs de la méthode scientifique au XVIIe :

« Pour montrer qu’une hypothèse est évidente, il ne suffit pas que tous les phénomènes la suivent ; au lieu de cela, si elle conduit à quelque chose de contraire à un seul des phénomènes, cela suffit pour établir sa fausseté. »

Son insistance sur l’existence du vide le place, aussi, en conflit avec de nombreux scientifiques éminents, y compris Descartes (peut-être aussi et surtout pour des raisons religieuses).Religion, philosophie, et littérature de la maturité [modifier]Antoine Arnauld, chef de file des jansénistes depuis la mort de Jean Duvergier de Hauranne, était en désaccord avec la Sorbonne au sujet d’une bulle d’Innocent X (mai 1653). Cherchant à défendre l’un de ses amis, le marquis de Liancourt, il s’attira les foudres de la Sorbonne. Les jansénistes cherchèrent un défenseur en la personne de Pascal.Pascal accepta, assurant qu’il savait (selon Sainte-Beuve) « comment on pourrait faire ce factum », mais qu’il ne pouvait promettre qu’« une ébauche » que d’autres se chargeraient de « polir ». Pascal commença à publier les lettres à partir du 23 janvier 1656 sous le pseudonyme de Louis de Montalte. Pascal lança une attaque mémorable contre la casuistique, une méthode morale populaire chez les penseurs catholiques, particulièrement les jésuites. Pascal dénonça la casuistique comme l’utilisation d’un raisonnement complexe pour justifier une morale laxiste. Sa méthode pour argumenter fut subtile : les Provinciales prétendaient être les Lettres écrites par Louis de Montalte à un provincial de ses amis et aux R.R.P.P. Jésuites sur le sujet de la morale et de la politique de ces pères. Il s’adresse à un ami qui vit en province à propos des discussions sur la morale et la théologie qui excitaient les cercles intellectuels et religieux de la capitale, particulièrement la Sorbonne. Pascal allia la ferveur d’un nouveau converti et l’esprit brillant d’un homme du monde, avec un style de la prose française inconnu jusque là. À côté de leur influence religieuse, les Provinciales ont été une œuvre littéraire populaire. Pascal se servit de l’humour, de la moquerie et de la satire méchante dans ses arguments, pour permettre une utilisation publique des lettres qui influenceront plus tard des écrivains français comme Voltaire, Jean-Jacques Rousseau, et surtout le Montesquieu des Lettres persanes.Les premières lettres défendent la position des jansénistes contre leurs adversaires jésuites ou dominicains (Thomistes), sur les questions du pouvoir prochain (Lettre I), de la grâce efficace ou suffisante (Lettre II), de la

possibilité que la grâce puisse manquer à un juste (Lettre III). À partir de la quatrième lettre, Pascal passe à l'offensive. Ses attaques contre les autorités prennent, selon Jean Lacouture, un ton polémique tel que « Voltaire lui-même n’a jamais peut-être atteint à cette fulgurance » : il nomma personnellement et par écrit un grand nombre de personnalités. Les dernières lettres montrent Pascal davantage sur la défensive – les pressions sur les jansénistes de Port-Royal pour qu’ils renoncent à leur enseignement sont croissantes pendant ce temps – et contiennent l’attaque contre la casuistique. La Lettre XIV présente une seule excuse : « Je voudrais avoir écrit une lettre plus courte, mais je n’en ai pas le temps. »La série de dix-huit lettres, publiées entre 1656 et 1657 par Pierre Le Petit, choque Louis XIV, qui a commandé en 1660 que le livre soit déchiqueté et brûlé. En 1661, l’école janséniste de Port-Royal était condamnée à son tour et fermée, ceci aboutissant à la signature d’une bulle papale condamnant l’enseignement des jansénistes comme hérétiques. La dernière lettre défiait le pape lui-même, provoquant Alexandre VII à condamner les lettres le 6 septembre 1657. Mais ceci n’empêcha pas la France cultivée de les lire.Le pape Alexandre VII, alors qu’il s’opposait publiquement à elles, était convaincu par les arguments de Pascal. Il ordonna une révision des textes casuistiques juste quelques années après, en 1665 et 1666. Le pape Innocent XI condamna le « laxisme » dans l’Église en 1679.Les Provinciales ont été largement diffusées dès leur parution, à plus d’une dizaine de milliers d’exemplaires.Voltaire les a jugées « le meilleur livre qui ait jamais paru en France », et quand on a demandé à Jacques Bénigne Bossuet quel livre il aurait aimé écrire, il a répondu, les Provinciales de Pascal.Jean Lacouture (Jésuites) cite d’autres appréciations, celles d’Henri Gouhier et de François Mauriac.Au sujet de l’impact qu’eurent les Provinciales dans leur contexte historique, Jean Lacouture cite l’historien Marc Fumaroli (voir Révolution copernicienne : l’image de l’Église ternie pendant les Lumières).Miracle [modifier]Quand Pascal revient à Paris, juste après avoir surveillé la publication de sa dernière lettre, sa croyance religieuse est renforcée par sa proximité avec un miracle apparent qui concerne sa nièce Marguerite Périer âgée de dix ans, dans la chapelle du couvent de Port-Royal. Sa mère Gilberte Périer raconte dans La vie de Monsieur Pascal qu’elle a consacrée à son frère :« Ce fut en ce temps-là qu’il plut à Dieu de guérir ma fille d’une fistule lacrymale, dont elle était affligée il y avait trois ans et demi. Cette fistule était d’une si mauvaise qualité, que les plus habiles chirurgiens de Paris la jugèrent incurable. Et enfin Dieu s’était réservé de la guérir par l’attouchement d’une Sainte-Épine qui est à Port-Royal-des-Champs ; et ce miracle fut attesté par plusieurs chirurgiens et médecins, et autorisé par le jugement solennel de l’Église. »Plus tard, les jansénistes et les catholiques utilisèrent pour leur défense ce miracle bien documenté. En 1728, le pape Benoît XIII s’en servit pour montrer que l’âge des miracles n’était pas terminé.Pascal mit dans son blason un œil surmonté d’une couronne d’épines, avec l’inscription Scio cui credidi (« Je sais à qui je crois »). Sa foi renouvelée, il se décida à écrire son œuvre testamentaire, inachevée, les Pensées.Pensées [modifier]Pascal ne put achever, avant de mourir, son travail théologique le plus important : un examen soutenu et logique de la défense de la foi chrétienne, avec pour titre original Apologie de la religion chrétienne.Après sa mort, de nombreuses feuilles de papier ont été trouvées lors du tri de ses effets personnels, sur lesquelles étaient notées des pensées isolées, feuilles regroupées en liasses dans un ordre provisoire mais parlant. La première version de ces notes éparses est imprimée en 1670 sous le titre Pensées de M. Pascal sur la religion et sur quelques autres sujets. Elles sont devenues très vite un classique. Parce que ses amis et les disciples de Port-Royal étaient conscients que ces « pensées » fragmentaires pouvaient mener au scepticisme plutôt qu’à la piété, ils ont caché les pensées sceptiques et ont modifié une partie du reste, de peur que le roi ou l’église n’en prenne offense alors que la persécution de Port-Royal avait cessé, et les rédacteurs ne souhaitaient pas une reprise de la polémique. Il a fallu attendre le XIXe siècle pour que les Pensées soient publiées complètement et avec le texte d’origine, tirées de l'oubli et éditées par le philosophe Victor Cousin.Les Pensées de Pascal sont largement considérées comme une des pièces maîtresses et une étape de la littérature française. En présentant ses observations sur un chapitre, Sainte-Beuve considérait ces pages comme les plus fines de la langue française. Will Durant, dans son onzième volume de l’Histoire des civilisations, le juge comme « le livre le plus éloquent en français ». Dans les Pensées, Pascal présente plusieurs paradoxes philosophiques : infini et néant, foi et raison, âme et matière, mort et vie, sens et vanité -- apparemment n’arrivant à aucune conclusion définitive sans l’appui de l’humilité et de la grâce. En les rassemblant, il développe le pari de Pascal.En l’honneur de ses contributions scientifiques, le nom de pascal a été donné à l’unité de pression du système international, à un langage de programmation et à la loi de Pascal (un principe important d’hydrostatique) et, comme mentionné ci-dessus, le triangle de Pascal et le pari de Pascal portent toujours son nom.Le développement de la théorie des probabilités est la contribution de Pascal la plus importante en mathématiques. À l’origine appliquée au jeu, elle est aujourd’hui utilisée dans les sciences économiques, particulièrement en science actuarielle. John Ross écrit :

« La théorie des probabilités et les découvertes qui la suivent ont changé la manière dont nous considérons l’incertitude, le risque, la prise de décision, et la capacité d’un individu ou de la société d’influencer le cours d’événements futurs ».

Cependant, il convient noter que Pascal et Fermat, qui effectuent les premiers travaux importants en théorie des probabilités, n’ont pas développé très loin ce champ d’études. Christiaan Huygens, étudiant la question à partir de la correspondance de Pascal et de Fermat, a écrit le premier livre sur le sujet. Abraham de Moivre et Pierre-Simon Laplace sont parmi les auteurs qui ont prolongé le développement de la théorie.

Au Canada, un concours annuel de mathématiques est appelé en son honneur « Concours Pascal » qui est ouvert à n’importe quel élève du Canada de moins de 14 ans et en 9e au plus.En informatique, le Pascal est un langage de programmation créé par Niklaus Wirth et nommé en l'honneur de Blaise Pascal.L’Université Clermont-Ferrand II a été baptisée à son nom.La banque de France a émis un billet de banque, le 500 francs Pascal, sa plus haute coupure de 1969 à 1994, à son effigie.En littérature, Pascal est considéré comme un des auteurs les plus importants de la période classique française et il est lu aujourd’hui en tant qu’un des plus grands maîtres de la prose française. Son utilisation de la satire et de l’esprit a influencé des polémistes postérieurs. On se souvient bien de la teneur de son travail littéraire à cause de sa forte opposition au rationalisme de René Descartes et de l’affirmation simultanée que l’empirisme philosophique était également insuffisant pour déterminer des vérités majeures.Barbey d’Aurevilly voit en Pascal un « Hamlet du catholicisme ». Baudelaire le paraphrase et lui consacre son poème « Le gouffre ».Une discussion à propos de Pascal occupe une place importante dans le film Ma nuit chez Maud du réalisateur français Eric Rohmer.La méditation pascalienne sur le divertissement trouve un prolongement dans le roman de Jean Giono, Un roi sans divertissement (1947). Giono emprunte le titre et la dernière phrase du livre à un passage des Pensées (fragment 142 de l’édition Brunschvicg) : « Un roi sans divertissement est un homme plein de misères ».Sœur Emmanuelle, dans son livre Vivre, à quoi ça sert ? (éditions J’ai Lu) s’appuie sur quelques principes de la pensée pascalienne qui fut un guide pour elle, tout au long de sa vie.Vers la fin de sa vie le sociologue Pierre Bourdieu a publié un livre de réflexions sur son domaine qui est intitulé Méditations pascaliennes 3

Liste des principales œuvres [modifier]La chronologie exacte des œuvres de Pascal est difficile à établir car de nombreux textes ne sont pas datés et ont été publiés longtemps après avoir été rédigés. Certains n’ont été connus qu’un siècle ou plus après le décès de Pascal et d’autres ne nous sont parvenus que de manière fragmentaire ou indirecte (notes de Leibniz ou correspondance, par exemple).

Essai pour les coniques (1642) Expériences nouvelles touchant le vide (1647) Récit de la grande expérience de l’équilibre des liqueurs (1648) Traité du triangle arithmétique (1654) La Règle des partis (1654) Les Provinciales (Correspondances 1656-1657) Élément de géométrie (1657) De l’Esprit géométrique et de l’Art de persuader (1657) Histoire de la roulette (1658) L’Art de persuader (1660) Pensées (1670, posthume)

Citation [modifier] « Je ne peux pas comprendre le tout si je ne connais pas les parties, et je ne peux pas comprendre les

parties si je ne connais pas le tout. » « Le silence éternel de ces espaces infinis m'effraye. » « Le cœur a ses raisons que la raison ne connaît pas. »

Références [modifier]Notes [modifier]

1. ↑ «Blaise Pascal à Rouen. Le Jansénisme normand. La maladie et la mort de Pascal : hypothèses nouvelles», in "Bulletin Historique et Scientifique de l'Auvergne", Tome LXXXIX, n°658, juillet 1978, pp.141-158 ; et, "Médecine et Hygiène", n°1717, 30 septembre 1987.

2. ↑ Julian Lowell Coolidge, The mathematics of great amateurs, Oxford University Press, Oxford, 1949

3. ↑ Bourdieu P., Méditations pascaliennes, Paris, Seuil, 1997; on a pu voir dans ce choix un geste démonstratif qui prend de contre pied l'approche emblématisée par le titre Méditations cartésiennes, pris naguère par le philosophe Edmund Husserl

Textes de Pascal [modifier]De très nombreuses éditions existent.

Jean Mesnard (Paris, Desclée de Brouwer, 1964-1992), qui contient tous les textes qui intéressent la vie ou l’œuvre de Pascal (y compris des actes notariés, etc.). Mais seuls 4 des 7 volumes ont parus à ce jour et ils ne contiennent ni Les provinciales ni les Pensées. On doit donc parfois avoir recours à d’autres éditions :

Pascal, Œuvres complètes, Louis Lafuma, Seuil, L'Intégral, 1963 Pascal, Œuvres complètes, éd. Michel Le Guern, coll. Bibliothèque de la Pléiade, Paris, Gallimard,

1998-1999 Pascal Blaise, Discours sur la religion et sur quelques autres sujets qui ont été trouvés après sa mort

parmi ses papiers, restitués et publiés par Emmanuel Martineau, Paris, Fayard-Armand Colin, 1992. Sur Pascal [modifier]

Marie Pérouse, L’Invention des Pensées de Pascal. Les éditions de Port-Royal (1670-1678), Éditions Honoré Champion, 2009.

Philippe Sellier , Essais sur l’imaginaire classique. Pascal - Racine - Précieuses et Moralistes - Fénelon., Éditions Honoré Champion, 2005.

(Ouvrage collectif), Blaise Pascal auvergnat : la famille à l’œuvre, catalogue d'exposition (Musées d’art de Clermont-Ferrand, 6 octobre-8 novembre 1981), Clermont-Ferrand, Association des amis et correspondants du Centre international Blaise Pascal, 1981.

Francesco Paolo Adorno, Pascal, Les Belles Lettres, 2000 (ISBN 2-251-76030-X). Vlad Alexandrescu, Le Paradoxe chez Blaise Pascal, Peter Lang, 1997 (ISBN 3-906754-72-3). Albert Béguin , Pascal, Paris, Seuil, 1952; nouvelle éd. 1981. André Bord, Pascal et Jean de la Croix, préface de Philippe Sellier, Paris, Beauchesne, 1987. André Bord, La vie de Blaise Pascal, Paris, Beauchesne, 2000. André Bord, Pascal vu par sa sœur Gilberte, Paris, Pierre Téqui, 2005. André Bord, Lumière et Ténèbres chez Pascal, Paris, Pierre Téqui, 2006. Léon Brunschvicg , Blaise Pascal, Paris, J. Vrin, 1953. Léon Chestov  : La Nuit de Gethsémani. Essai sur la philosophie de Pascal, Grasset, 1923 (en) Francis X. J. Coleman, Neither Angel Nor Beast : The Life and Work of Blaise Pascal, New York,

Londres, Routledge and Kegan Paul, 1986. Jacques Darriulat , L’Arithmétique de la Grâce: Pascal et les carrés magiques, Paris, les Belles lettres,

1994. Dominique Descotes, Pascal : biographie, étude de l’œuvre, Paris, Albin Michel, 1994. Gérard Ferreyrolles, Pascal et la raison du politique, PUF, 1984. Jean-Louis Gardies, Pascal entre Eudoxe et Cantor, Paris, J. Vrin, 1984. Henri Gouhier , Blaise Pascal : conversion et apologétique, Paris, Vrin, 1986. Henri Gouhier, Blaise Pascal, commentaires, Paris, Vrin, 1966. Pierre Guenancia, Du vide à Dieu : essai sur la physique de Pascal, Paris, Maspero, 1976. Thomas More Harrington, Pascal philosophe, Paris, C.D.U.-S.E.D.E.S., 1982. Pierre Humbert, L’Œuvre scientifique de Blaise Pascal, Paris, Albin Michel, 1947. Pierre Magnard, Nature et histoire dans l'apologétique de Pascal, Paris, Belles-Lettres, 1975. Pierre Magnard, Pascal - La clé du chiffre, La Table ronde, 2007. Pierre Magnard, Pascal ou l'art de la digression, Ellipses, 1995. Pierre Magnard, Le Vocabulaire de Pascal, Ellipses, 2001. Jean Mesnard , Pascal et les Roannez, Paris, Desclée De Brouwer, 1965, 2 vol. Jacques Moutaux (dir.), Pascal et la géométrie, Mont-Saint-Aignan, CRDP de Rouen : IREM de Rouen,

1993. Hervé Pasqua, Pascal, penseur de la grâce, Téqui, 2000. Martine Pécharman (dir.), Pascal. Qu'est-ce que la vérité ?, P.U.F, 2000. Maurice Pontet, Pascal et Teilhard, témoins de, Jésus-Christ, Desclée de Brouwer, Paris, coll.

« Christus » n° 27, 1968, 221p. Jean-Félix Nourrisson , Pascal, physicien et philosophe, Paris, Librairie académique Didier, 1885. Philippe Sellier , Pascal et saint Augustin, Albin Michel, 1995. Tetsuya Shiokawa, Pascal et les miracles, Paris, Nizet, 1977. Philippe-Joseph Salazar , Efficacité rhétorique exemplaire. Les Pensées dans les Causeries du lundi de

Sainte-Beuve, in R. Behrens, A. Gipper, V. Mellinghoff-Bourgerie (dir.), Croisements d’anthropologies.

Pascals Pensées im Geflecht der Anthropologien, Heidelberg, Universitätsverlag Winter, 2005, p. 331-344 (ISBN 3-8253-5035-5).

Laurent Thirouin, Le Hasard et les règles : le modèle du jeu dans la pensée de Pascal. Préface de Jean Mesnard. Paris : Vrin, 1991 (222 p.). Prix Biguet de l’Académie Française.(ISBN 2-7116-1054-3).

Paul Valéry , « Variation sur une pensée », 1923.

http://fr.wikipedia.org/wiki/Pens%C3%A9esPenséesUn article de Wikipédia, l'encyclopédie libre.Les Pensées sont une œuvre posthume de Blaise Pascal, publiée en 1670 soit huit ans après sa mort. Pascal y réunit des notes qu'il destinait à l'élaboration d'une apologie de la religion chrétienne. L'œuvre restée à l'état d'ébauche affichait donc un caractère fragmentaire après sa mort.En ont découlé deux façons différentes d'éditer le texte après sa mort. La première consiste à organiser les fragments selon un ordre supposé voulu par l'auteur, c'est le cas par exemple de l'édition Brunschvicg, qui va jusqu'à proposer des titres de chapitre sous lesquels il réunit des fragments. Mais on peut aussi effectuer un travail sur la genèse de l'œuvre. Dès lors on s'aperçoit que Pascal procédait en réunissant les différents fragments dans différentes « liasses », suivant un plan de travail non plus chronologique mais thématique. Sellier, en examinant par exemple les origines des papiers, propose donc une édition dans laquelle il vise à reconstituer ces différentes liasses telles qu'elles devaient être au moment de la mort de Pascal.Sommaire[masquer]

1 La misère de l'Homme sans Dieu 2 Le divertissement 3 Esprit de géométrie et esprit de finesse 4 La disproportion de l'Homme 5 Explication de texte - Les deux infinis

La misère de l'Homme sans Dieu [modifier]Ce domaine est celui qui a suscité le plus de réactions. En effet, d'après Pascal, l'Homme sans Dieu est impuissant, cette misère est causée par la grandeur de l'Homme. Semblable aux animaux qui ne sont pas miséreux, l'Homme se sent comme tel car il a conservé le souvenir d'une époque où il était dans une situation beaucoup plus haute, le souvenir du paradis perdu suite au péché originel. Il y a donc une contradiction entre ce qu'il est et ce qu'il aspire à être. Pour s'extraire de cette réalité, il essaie de s'élever : « l'appel à Dieu », selon Pascal. Il ne sera, par conséquent, misérable qu'éloigné de Dieu.L'amour de Dieu est avant tout l'oeuvre d'une bonne volonté, c'est-à-dire la fidélité de l'Homme à l'appel d'un être supérieur. La croyance en Dieu est une réponse aux multiples questions que se pose l'Homme. La croyance en Dieu permet de lutter contre les « puissances trompeuses » qui faussent le jugement de l'Homme (imagination, coutume, et amour-propre).Le divertissement [modifier]Pascal redéfinit le divertissement. Il le considère dans la perspective de la foi chrétienne et de ses convictions jansénistes. Il n’est pas à comprendre au sens ludique du terme : travailler est aussi un divertissement puisque le verbe "se divertir" vient du latin di-vertere qui signifie en fait "se détourner de".L'homme cherche à oublier sa condition par le divertissement. Cette nécessité de sortir de son malheur explique le dédain de l'Homme pour le repos : lorsque l'Homme ne fait rien, il pense à son triste sort : « Les Hommes n'ayant pu guérir la mort, la misère, l'ignorance, ils se sont avisés, pour se rendre heureux, de n'y point penser » (pensée 133).Même si tous nos actes ne nous permettent pas de répondre à nos angoisses, et ce n'est pas leur rôle, ils ont le mérite de nous aérer l'esprit. Activité est un bonheur dont l'Homme ne doit pas se passer, celui-ci le recherchant continuellement.L’homme se trouve dans une impasse. L’agitation engendre le besoin de repos. Le repos engendre l’ennui, donc la recherche d’agitation. L’homme ne trouve le bonheur ni dans le repos ni dans le divertissement. Pour Pascal il n’y a de recherche de bonheur qu’en Dieu. Comme en témoigne Le Mémorial.Esprit de géométrie et esprit de finesse [modifier]L'Homme est partagé entre sa raison et son jugement (sentiment). Ainsi, il conçoit différemment la Justice selon les pays ou même les régions car celle-ci fait appel aux sentiments pour définir ce qui est juste. Or, la sensibilité est subjective (pensée 512).

La disproportion de l'Homme [modifier]Pascal s'adresse à la sensibilité de ses lecteurs pour les persuader, il désire provoquer chez eux un sentiment de vertige, en passant de l'infiniment petit à l'infiniment grand. Il veut réduire l'Homme à sa condition, lui démontrant qu'il n'est rien. L'objectif est de débarrasser l'Homme de sa présomption, il veut l'amener à contempler son univers et le monde qui l'entoure, afin qu'il accepte l'autorité et la supériorité divine (pensée 196).