A JOURNEY THROUGH THE LIFE HISTORY BLAISE PASCAL

BLAISE PASCAL

Born                     : June 19, 1623, Clermont-Ferrand, France

Nationality           :  French

Religion                :  Ronal Catholic

Era                       :  17^th Century Philosophy

School                  :  Jansenism Proto-Existentialism

Main Interest        : Theology, Physics, Mathematics

Notable Ideas       : Pascal’s Wager

  Pascal’s Triangle

  Pascal’s Law

  Pascal’s Theorem

Died                     : August 19, 1662, Paris, France

INTRODUCTION

Blaise Pascal was a French physicist, inventor, mathematician, writer and philosopher.  He was a child prodigy who was educated by his father, a tax collector in Rouen.  Pascal's earliest work was in the natural and applied sciences where he made important contributions to the study of fluids, and clarified the concepts of pressure and vacuum by generalizing the work of Evangelista Torricelli.  Pascal also wrote in defense of the scientific method.

In 1642, while still a teenager, he started some pioneering work on calculating machines.  After three years of effort and fifty prototypes, he built 20 finished machines over the following ten years, establishing him as one of the first two inventors of the mechanical calculator.

Pascal had poor health, especially after his 18^th year, and his death came just two months after his 39^th birthday.

EARLY LIFE AND EDUCATION

Pascal was born in Clermont-Ferrand, which is in France's Auvergne region.  He lost his mother, Antoinette Begon, at the age of three.  His father, Étienne Pascal who also had an interest in science and mathematics, was a local judge and member of the "Noblesse de Robe". Pascal had two sisters, the younger Jacqueline and the elder Gilberte.

In 1631, five years after the death of his wife Étienne Pascal moved with his children to Paris.  The newly arrived family soon hired Louise Delfault, a maid who eventually became an instrumental member of the family.  Étienne, who never remarried, decided that he alone would educate his children, for they all showed extraordinary intellectual ability, particularly his son Blaise.  The young Pascal showed an amazing aptitude for mathematics and science.

Particularly of interest to Pascal was a work of Desargues on conic sections.  Following Desargues' thinking, the 16-year-old Pascal produced, as a means of proof, a short treatise on what was called the "Mystic Hexagram", Essai pour les coniques ("Essay on Conics") and sent it first serious work of mathematics to Père Mersenne in Paris; it is known still today as Pascal's theorem.  It states that if a hexagon is inscribed in a circle, then the three intersection points of opposite side lie on a line (called the Pascal line).

Pascal's work was so precocious that Descartes was convinced that Pascal's father had written it. When assured by Mersenne that it was, indeed, the product of the son and not the father, Descartes dismissed it with a sniff:  "I do not find it strange that he has offered demonstrations about conics more appropriate than those of the ancients," adding, "but other matters related to this subject can be proposed that would scarcely occur to a 16-year-old child."

In 1642, in an effort to ease his father's endless, exhausting calculations, and recalculations, of taxes owed and paid.  Pascal, not yet 19, constructed a mechanical calculator capable of addition and subtraction, called Pascal's calculator or the Pascaline.  Of the eight Pascalines known to have survived, four are held by the Musée des Arts et Métiers in Paris and one more by the Zwinger museum in Dresden, Germany, exhibit two of his original mechanical calculators.  Pascal continued to make improvements to his design through the next decade, and he refers to some 50 machines that were built to his design.

Pascal continued to influence mathematics throughout his life.  In 1653 he described a convenient tabular presentation for binomial coefficients, now called Pascal's triangle.  He defines the numbers in the triangle by recursion: Call the number in the (m + 1)^th row and (n + 1)^th column t_mn.

Then t_mn = t_m–1,n + t_m,n–1, for m = 0, 1, 2, ... and n = 0, 1, 2, ... The boundary conditions are t_m,−1 = 0, t_−1,n = 0 for m = 1, 2, 3, ... and n = 1, 2, 3, ... The generator t₀₀ = 1. Pascal concludes with the proof.

t_mn = (m+n) (m+n-1)….. (m+1)/n(n-1)…..1

After a religious experience in 1654, Pascal mostly gave up work in mathematics.

CONTRIBUTIONS TO THE PHYSICAL SCIENCES

Pascal's work in the fields of the study of hydrodynamics and hydrostatics centered on the principles of hydraulic fluids.  His inventions include the hydraulic press and the syringe.  He proved that hydrostatic pressure depends not on the weight of the fluid but on the elevation difference.  He demonstrated this principle by attaching a thin tube to a barrel full of water and filling the tube with water up to the level of the third floor of a building.  This caused the barrel to leak, in what became known as Pascal's barrel experiment.

By 1646, Pascal had learned of Evangelista Torricelli's experimentation with barometers. Having replicated an experiment that involved placing a tube filled with mercury upside down in a bowl of mercury, Pascal questioned what force kept some mercury in the tube and what filled the space above the mercury in the tube. At the time, most scientists contended that, rather than a vacuum, some invisible matter was present. This was based on the Aristotelian notion that creation was a thing of substance, whether visible or invisible; and that this substance was forever in motion. Furthermore, "Everything that is in motion must be moved by something,"Aristotle declared.  Therefore, to the Aristotelian trained scientists of Pascal's time, a vacuum was an impossibility. How so? As proof it was pointed out:

·        Light passed through the so-called "vacuum" in the glass tube.

·        Aristotle wrote how everything moved, and must be moved by something.

·        Therefore, since there had to be an invisible "something" to move the light through the glass tube, there was no vacuum in the tube. Not in the glass tube or anywhere else. Vacuums – the absence of any and everything – were simply an impossibility.

PASCAL’S DEATH

In 1662, Pascal's illness became more violent, and his emotional condition had severely worsened since his sister's death.  Aware that his health was fading quickly, he sought a move to the hospital for incurable diseases, but his doctors declared that he was too unstable to be carried.  In Paris on 18 August 1662, Pascal went into convulsions and received extreme unction.  He died the next morning, his last words being "May God never abandon me," and was buried in the cemetery of Saint-Étienne-du-Mont.

LEGACY

In honor of his scientific contributions, the name Pascal has been given to the SI unit of pressure, to a programming language, and Pascal's law and as mentioned above, Pascal's triangle and Pascal's wager still bear his name.

WORKS

·        Experiences nouvelles touchant le vide (1647)

·        Traité du triangle arithmétique [Treatise on the arithmetic triangle] (1653)

·        Lettres provinciales [The provincial letters] (1656–57)

·        De l'Esprit géométrique [On the geometrical spirit] (1657 or 1658)

·        Écrit sur la signature du formulaire (1661)

·        Pensées [Thoughts] (incomplete at death)

REFERENCE

www.wikipedia.org.in