Pascal, Blaise (blĕz päskäl`), 1623–62, French scientist and religious philosopher. Studying under the direction of his father, a civil servant, Pascal showed great precocity, especially in mathematics and science. Before he was 16 he wrote a paper on conic sections which won the respect of the mathematicians of Paris; at 19 he invented a calculating machine. Credited with founding the modern theory of probability, Pascal also discovered the properties of the cycloid and contributed to the advance of differential calculus. In physics his experiments increased knowledge of atmospheric pressure through barometric measurements and of the equilibrium of fluids (see Pascal's law Pascal's law (päskälz`)
..... Click the link for more information. ). As a young man, Pascal came under the influence of Jansenism, and in 1651 his sister Jacqueline, who had also embraced Jansenist beliefs, entered the convent at Port-Royal, the center of the movement. As a result of the death of his father and of his own narrow escape from death, Pascal in 1654 experienced what he called a "conversion" and thereafter turned much of his attention to religion. When Antoine Arnauld, a noted Jansenist, was attacked by the Jesuits, Pascal championed him in his Lettre escrite à un provincial (1656). Those Provincial Letters, rendered into Latin, quickly circulated throughout Europe, and they still hold a leading place in the literature of polite irony. Pascal's religious writings were posthumously published as Pensées de M. Pascal sur la religion et sur quelques autres sujets (1670). For a modern edition see Thoughts: An Apology for Christianity (tr. 1955). In the Pensées, famous both as a religious and philosophical classic, Pascal states his belief in the inadequacy of reason to solve man's difficulties or to satisfy his hopes. He preached instead the final necessity of mystic faith for true understanding of the universe and its meaning to man.

Bibliography

See biographies by A. J. Krailsheimer (1980), H. H. Davidson (1983); studies by E. Cailliet (1944, repr. 1973), R. Hazelton (1974), and S. E. Melzer (1986).

Pascal, Blaise

(born June 19, 1623, Clermont-Ferrand, France—died Aug. 19, 1662, Paris) French mathematician, physicist, and religious philosopher. The son of a mathematician, he was a child prodigy, earning the envy of René Descartes with an essay he wrote on conic sections in 1640. In the 1640s and '50s he made contributions to physics (formulating Pascal's law) and mathematics (working on the arithmetic triangle, inventing a calculating machine, and contributing to the advance of differential calculus). For work done in his early years, he is regarded as the founder of the modern theory of probability. At the same time, he became increasingly involved with Jansenism. Les Provinciales were a series of letters defending Jansenism and attacking the Jesuits. His great work of Christian apologetics, Apologie de la religion chrétienne, was never finished, but he put together most of his notes and fragments between 1657 and 1658; these were published posthumously as Pensées (1670). He returned to scientific work, contributing to the Élements de géométrie and publishing his findings on cycloid curves, but he soon returned to devotional life and spent his last years helping the poor. The pascal was named in his honour. See also Pascal's wager.