Blaise Pascal

1623-1662

French Mathematician and Philosopher

Amathematical prodigy who first made a name for himself at age 16, Blaise Pascal had a meteoric career that concluded before he was 40. His efforts were further curtailed by hisgrowing interest in a religious sect during the latter half of his life. Yet during his brief years of fruitful work, he helped develop the foundations of projective geometry with Girard Desargues (1591-1661); established probability theory with Pierre de Fermat (1601-1665); made possible new forms of calculus; and created a number of inventions, including the syringe, the hydraulic press, and the world's first mechanical calculator.

Today the French town of Clermont, or Clermont-Ferrand as it is now known, is famous as the birthplace of three things: Michelin tires, the Crusades (Pope Urban II preached the sermon beginning the First Crusade here in 1095), and Blaise Pascal. Son of mathematician and civil servant Etienne Pascal (1588-1651) and his wife Antoinette Bégon, Pascal came from a tightly knit family. His mother died when he was three, and this only drew him closer to sisters Gilberte and Jacqueline, as well as his father.

When Pascal was eight, the family moved to Paris, and there he began to excel as a student of mathematics and ancient languages. He and his father also became associated with the discussion group that centered around Marin Mersenne (1588-1648), and included such luminaries as René Descartes (1596-1650) and Fermat. The family moved to Rouen in 1639, but Pascal and his father continued to visit Paris, and in the following year the 16-year-old boy presented a pamphlet that impressed no less a figure than Descartes.

The title was Essai sur les coniques, and Pascal's purpose in writing it was to clarify ideas Desargues had presented, using highly complex and confusing terminology, in a 1639 publication. As he continued work on it, however, the youth went far beyond Desargues's original point, developing a theorem concerning what came to be known as "Pascal's mystic hexagram." According to the theorem, from which he deduced some 400 corollary propositions, the three points of intersection of the pairs of opposite sides of a hexagon inscribed in a conic are collinear. Along with Desargues's ideas, these helped form the basis for projective geometry.

Despite health problems in the 1640s, Pascal developed his calculator, which used cogged wheels to perform its computations, and in 1649 received from the French crown a monopoly for its manufacture. In fact production of the calculator turned out to be prohibitively expensive in that preindustrial era, but the mechanical calculators that did eventually appear—andwhich proliferated in the era before electronic devices—were modeled on Pascal's design.

From the age of 23, Pascal became increasingly involved with the Jansenists, a sect that believed in predestination and divine grace as the sole means of salvation. (Though they called themselves Catholics, the Jansenists most closely resembled Calvinists, and in fact the sect was later declared heretical by the Vatican.) Despite his growing preoccupation with spiritual matters, Pascal during this period conducted a number of experiments to measure atmospheric and barometric pressure, and used the information he gathered to invent the syringe and the hydraulic press.

In 1647, the family returned to Paris, and the father died three years later. Pascal in 1654 had a riding accident that nearly took his life, and as a result decided to join his sister Jacqueline at the Jansenist convent of Port-Royal. Thereafter his scientific work tapered off, while his writings in religious philosophy increased; however, just before this happened, an exchange of letters with Fermat regarding a game of dice led to the development of probability theory.

Also during the late 1650s, Pascal resumed his interest in geometry. Among the figures that attracted his attention were the arithmetic triangle—his work ultimately influenced the general binomial theorem later put forward by Sir IsaacNewton (1642-1727)—and the cycloid. The latter is a curve traced by the motion of a fixed point on the circumference of a circle rolling along a straight line. Though mathematicians had been investigating cycloids for many years, Pascal was able to solve most of the remaining problems involving them in just eight short days.

As it turned out, time was running short for Pascal, who had always been sickly. In 1662, he devoted himself to designing a public transportation system of carriages for Paris, but before the system became operational, he died on August 19 of a malignant stomach ulcer at his sister Gilberte's home.

This is the complete article, containing 739 words (approx. 2 pages at 300 words per page).