**PASCAL, Blaise** (1623-62). Regarded as a brilliant man in his own time,
Blaise Pascal made contributions to science, mathematics, and religious
philosophy for all time. His works 'Les Provinciales' (Provincial Letters)
and 'Pensees' (Thoughts), both religious, are considered masterpieces of
prose.

Pascal was born in Clermont-Ferrand in central France on June 19, 1623. His father was a highly placed civil official. In 1631 the family moved to Paris. The elder Pascal took charge of his son's education. The boy proved to be a child prodigy. At the age of 12 he reputedly figured out a proposition of Euclidean geometry by himself.

By the time he was 17 he had written an essay on conic sections (see Geometry). A pioneering work in projective geometry, it contained a theorem on conic sections that was named for him. Between 1642 and 1644 Pascal constructed the first digital calculating machine in order to expedite his father's work with figures (see Calculator).

In 1646 Pascal was converted to Jansenism, a Roman Catholic reform movement, when he met two disciples of the abbot of St-Cyran. St-Cyran had brought to the convent of Port-Royal near Paris the Jansenist doctrines of a repudiation of free will and a belief in divine grace, rather than good works, as the key to salvation. In science Pascal's further studies in geometry, hydrodynamics, and hydrostatic and atmospheric pressure led him to the invention of the syringe and the hydraulic press. He described his experiments in two treatises (published after his death) in which he also established the principle of hydrostatics now known as Pascal's law (see Hydraulics).

Always in frail health, Pascal became ill from overwork. To relax he took up courtly social life, read philosophy, and resumed mathematical work. For friends who gambled, he calculated chances of loss or gain; this led him into pioneering work on probability theory and to the independent discovery of the arithmetical triangle. In a treatise on numerical powers, he deduced the principles of integral calculus.

On the night of Nov. 23, 1654, Pascal had what he described as a religious experience. He then went into retreat at Port-Royal. At this time a dispute between Jansenists and Jesuits over questions of divine grace and free will reached a crisis. An opponent of the Jesuits, Antoine Arnauld, was on trial before the faculty of theology at the Sorbonne in Paris for controversial writings. Between January 1656 and March 1657 Pascal, using the pen name Louis de Montalte, wrote 18 letters defending Arnauld. 'Les Provinciales' captivated the public with their wit, style, and reasoning (see French Literature).

In 1657-58 he made notes for a book on the justification of Christianity. The notes were published after his death as 'Pensees'. In them Pascal argued that reason is but a limited tool, incapable of yielding ultimate truths about God, humanity, and the universe, and that human beings--both ignorant and corrupt--must, therefore, rely on faith. Pascal's work on the 'Pensees' was terminated by a long illness resulting from a malignant stomach ulcer. He died in Paris on Aug. 19, 1662.

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**Excerpted from The Complete Reference Collection**

**Copyright © 1994, 1995, 1996, 1997 The Learning Company, Inc. All
Rights Reserved.**

In 1624, the German mathematician **Wilhelm Schickard** built a calculating
machine for the creation of astronomical tables, probably the **first use
of gears in a calculator**. In 1642 **Pascal devised the first automatic
adding machine**, used for accountancy calculations. This had gears which
were turned and engaged during the adding process. The German philosopher
and mathematician Gottfried Leibniz improved on Pascal's design, producing
in 1671 a stepped-wheel machine to perform multiplication, the principles
of which have been used in almost every subsequent mechanical calculator.

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**Excerpted from The Oxford Interactive Encyclopedia**

**Developed by The Learning Company, Inc. Copyright (c) 1997 TLC Properties
Inc. All rights reserved.**

.

**Pascal, Blaise**

(1623–62) French mathematician, physicist, and religious philosopher.
A child prodigy, before the age of 16 he had proved an important theorem
in the projective geometry of conics, and at 19 constructed **the first
mechanical calculator to be offered for sale**. He discovered that air
has weight, confirmed that vacuum could exist, and derived the principle
that the pressure of a fluid at rest is transmitted equally in all directions.
He also founded the theory of probabilities, and developed a forerunner of
integral calculus. He later entered a Jansenist convent, where he wrote two
classics of French devotional thought, the Lettres provinciales (1656–57),
directed against the casuistry of the Jesuits, and Pensées (1670),
a defence of Christianity.

**(Excerpted from Oxford World Encylopaedia)**