Mathematician:Blaise Pascal

Mathematician
French mathematician and philosopher who explored probability theory and projective geometry.

Most famous for the construction now commonly known as Pascal's Triangle.

Also known for:
 * Inventing the wrist watch
 * Age 17 -- 19: Inventing the calculating machine
 * Age 23: Progressing the concept of the mercury-tube barometer (extending and confirming 's work). Used it to observe the difference in atmospheric pressure according to the weather, and also (by a famous experiment performed on Puy de Dôme), according to differences in altitude
 * Inventing the syringe (as a byproduct of his work on the barometer)
 * Organising the first public transportation system

Nationality
French

History

 * Born: June 19, 1623, Clermont (now Clermont-Ferrand), Auvergne, France
 * 1631: Moved to Paris
 * 1646: Experienced his "first conversion", when he felt compelled to turn away from the world towards God, but this did not last
 * 1654: Had a second religious vision, which again turned him away from mathematics and towards mysticism
 * 1658: Briefly returned to mathematics as a way of taking his mind off a toothache
 * Died: August 19, 1662, Paris, France of a brain tumour and stomach cancer.

Theorems and Definitions

 * Pascal's Wager (employing probability theory to answer deep philosophical questions)
 * Pascal's Triangle
 * Pascal's Law (a physical law lying at the basis of hydrostatics)
 * Pascal's Rule
 * Pascal's Theorem (concerning a hexagon inscribed in a conic section)

Books and Papers

 * 1639: Essai pour les coniques (in which Pascal's Theorem appears)
 * 1647: Experiences nouvelles touchant le vide
 * 1653: Traité du triangle arithmétique (in which Pascal's Triangle is discussed)
 * 1656–7: Lettres provinciales (under a fictitious name)
 * 1657 or 1658: De l'Esprit géométrique
 * 1658: Traité des sinus du quart de cercle (Treatise on the Sines of a Quadrant of the Circle)
 * 1661: Écrit sur la signature du formulaire
 * Also: Pensées (incomplete at his death)

Notable Quotes

 * On the barometer: This knowledge can be very useful to farmers, travellers, etc., to learn the present state of the weather, and that which is to follow immediately, but not to know that which is to come in three weeks.


 * The heart has its reasons that the reason does not know.


 * Men never do evil so completely and cheerfully as when they do it from religious conviction.