Blaise Pascal

Lore & Background

Pascal was a child prodigy educated by his father Étienne Pascal, a tax collector in Rouen. His earliest mathematical work was on projective geometry; he wrote a treatise on conic sections at age 16. He corresponded with Pierre de Fermat on probability theory, influencing modern economics and social science. In 1642, he began work on calculating machines (Pascal's calculators, later Pascalines), establishing him as one of the first two inventors of the mechanical calculator. He made contributions to the study of fluids, clarifying pressure and vacuum by generalizing Torricelli's work. The SI unit for pressure is named for Pascal. In 1647, he rebutted Aristotle and Descartes on the vacuum. He is also credited as the inventor of modern public transportation, having established the carrosses à cinq sols, the first modern public transport service, shortly before his death in 1662. In 1646, he and his sister Jacqueline identified with Jansenism. After a religious experience in late 1654, he wrote influential works on philosophy and theology, including the Lettres provinciales and the Pensées, the latter containing Pascal's wager. He also wrote on the arithmetical triangle and, between 1658 and 1659, on the cycloid and its use in calculating volume of solids. Pascal died in Paris at age 39.

Reader's Guide

Pascal was born in Clermont-Ferrand, in France's Auvergne region. He lost his mother at age three. His father Étienne, an amateur mathematician, was a local judge and member of the Noblesse de Robe. Pascal had two sisters: Jacqueline and Gilberte. In 1631, Étienne moved the family to Paris. Étienne educated his children alone. By age 12, Pascal had rediscovered Euclid's first 32 propositions. At 16, he wrote Essai pour les coniques (Essay on Conics), containing Pascal's theorem. In 1638, Cardinal Richelieu defaulted on government bonds, reducing Étienne's worth from nearly 66,000 livres to less than 7,300. Étienne fled Paris due to opposition to Richelieu's fiscal policies, leaving his children with Madame Sainctot. After Jacqueline performed in a play with Richelieu, Étienne was pardoned and in 1639 appointed king's commissioner of taxes in Rouen. In 1642, Pascal built a mechanical calculator (Pascaline) to help his father with tax calculations. Eight Pascalines survive. The calculator was not a commercial success, becoming a toy and status symbol. Pascal presented the first mechanical calculator to Queen Christina of Sweden in 1632. In 1654, prompted by the Chevalier de Méré, Pascal corresponded with Fermat on gambling problems, founding probability theory. Pascal's Traité du triangle arithmétique (written 1654, published 1665) described Pascal's triangle.

Did You Know?

• Pascal's earliest mathematical work was on projective geometry, and he wrote a treatise on conic sections at age 16.
• The SI unit for pressure is named after Pascal.
• Pascal's calculator, the Pascaline, could perform addition and subtraction.
• Pascal's wager is a probabilistic argument for belief in God, found in his Pensées.
• Pascal established the carrosses à cinq sols, the first modern public transport service, shortly before his death.

Notable Quotes (Wikiquote)

"Blaise Pascal (19 June 1623 – 19 August 1662) was a French mathematician, logician, physicist and theologian." — Blaise Pascal "Note: All quotes from the Pensées are on that page." — Blaise Pascal "For as old age is that period of life most remote from infancy, who does not see that old age in this universal man ought not to be sought in the times nearest his birth, but in those most remote from it?" — Blaise Pascal "Je n'ai fait celle-ci plus longue que parce que je n'ai pas eu le loisir de la faire plus courte." — Blaise Pascal