Blaise Pascal (1623-1662), a French philosopher and scientist, was one of the greatest and most influential mathematical writers of all time. He was also an expert in many fields, including various languages, and a well-versed religious philosopher.

Born at Clermont-Ferrand on June 19, 1623, Pascal’s father was Etienne Pascal, a counsellor of the king

who later became the president of the Court of Aids at Clermont. His mother died in 1626. The Pascal

family settled in Paris in 1631.

At a tender age of 12, Pascal began participating in the meetings of a

mathematical academy. He learned different languages from his father, Latin

and Greek in particular, but Pascal Sr. didn’t teach him mathematics. This increased the curiosity of young Pascal, who went on to experiment with geometrical figures, even formulating his own names for standard

geometrical terms.

In 1640, the Pascal family drew up stakes once again. They moved

to Rouen, France, where Blaise's father had been appointed to

collect taxes. Within just a year of moving, Blaise published his

first written work, Essay on Conic Sections. The essay

constituted an important leap forward in projective geometry,

which involved transferring a 3-D object onto a 2-D field.

In 1646, Etienne was seriously injured in an accident that rendered him housebound. The accident created a shift in the whole

family's religious beliefs. The Pascal's had never fully embraced the local Jesuits'

ideas. After Etienne's accident, a visit from a group of Jansenists led the family to

convert to that belief system. During the year that Etienne convalesced, two

Jansenists brothers watched over Blaise. As a result of their influence, Blaise became

devoutly religious.

Laying foundation for today’s probability theory

Work in barometric pressureTheological writingsPascalinePenseesProvincial Letters

His contributions were in:

Pascal started working on a book, Essay on Conics. The book was published in 1640, and its highlight was the “mystic hexagram”, a theorem related to the co-linearity of intersections of lines. It also had hundreds of propositions on conic sections, and influences from Apollonius and his successors. The book gained publicity not only because of the writer’s young age, 16, but also due to its unique accounts about tangency, and several other qualities.

In 1642, at age 18, inspired by the idea of making his father's job of calculating taxes easier, Pascal invented an early calculator, dubbed the Pascaline. (German polymath

William Schickard had developed and manufactured an earlier version of the digital

calculator in 1624.) The Pascaline was a numerical wheel calculator with eight movable dials, each representing a numerical digit, such as ones, tens and hundreds. It was capable of adding, subtracting, multiplying and dividing.

At the end of the 1640s, Pascal temporarily focused his experiments on

the physical sciences. Following in Evangelista Torricelli’s footsteps, Pascal

experimented with how atmospheric pressure could be estimated in terms of

weight. By taking readings of the barometric pressure at various

altitudes, Pascal validated Torricelli's theory concerning the cause of

barometrical variations.

ONE OF THE MOST INTERESTING NUMBER PATTERNS IS PASCAL'S TRIANGLE. TO BUILD THE TRIANGLE, START WITH "1" AT THE TOP, THEN CONTINUE PLACING NUMBERS BELOW IT IN A TRIANGULAR PATTERN. EACH NUMBER IS THE TWO NUMBERS ABOVE IT ADDED TOGETHER (EXCEPT FOR THE EDGES, WHICH ARE ALL "1").

Pascal’s contributions to hydrostatics, particularly his experimentations with

the barometer and his theoretical work on the equilibrium of fluids, were made public one year after his death. The development of probability theory

is often considered to be the most significant contributions in the history

of mathematics.

The Treatise on the Equilibrium of Liquids by Pascal is an extension to Simon Stevin’s research on the hydrostatic paradox and explains what may be termed as the final law of hydrostatics; the famous Pascal’s principle. Pascal is known for his theories

of liquids and gases and their interrelation, and also his work regarding the relationship between the dynamics of

hydrodynamics and rigid bodies.

Post-Port Royal, perhaps Pascal’s most important to mathematics dealt with the issues related to the cycloid; a

curve, with the area of which the best mathematicians of the day were

occupied. Pascal introduced most of his theorems without proof, thus issuing a

challenge to his contemporaries, for instance Christopher Wren, John Wallis

and Christian Huygens, who happily accepted and figured them out. He also put forward his own solutions, “Amos Dettonville”, an assumed alias. Later,

many mathematicians often referred to him by this alias.

The mathematical theory of probability became popular when a communication

between Pascal and Pierre de Fermat disclosed that both had concluded to

almost similar results. Pascal designed a treatise on the subject, which was also published after his death, though only a few parts of it have survived. Pascal was

always concise and sharp when it came to mathematics.

Aside from their religious influence, the Provincial Letters were popular as a literary work. Pascal's use of humour, mockery, and vicious satire in his arguments made the letters ripe for public consumption, and influenced the prose of later French writers like Voltaire and Jean-Jacques Rousseau.The Provincial Letters also received praise. For example, Charles Perrault wrote of the Letters: "Everything is there—purity of language, nobility of thought, solidity in reasoning, finesse in raillery, and throughout an agrément not to be found anywhere else.

Pascal's Pensées is widely considered to be a masterpiece, and a landmark in French prose. When commenting on one particular section , Sainte-Beuve praised it as the finest pages in the French language. Will Durant hailed it as "the most eloquent book in French prose. In Pensées, Pascal surveys several philosophical paradoxes: infinity and nothing, faith and reason, soul and matter, death and life, meaning and vanity—seemingly arriving at no definitive conclusions besides humility, ignorance, and grace. Rolling these into one he develops Pascal's Wager.

Pascal struggled with insomnia and a painful digestive disorder called dyspepsia

from the time he was a teen. Regarding his physical health, he was described as “a

man of slight build with a loud voice and somewhat overbearing manner”. He lived most of his adult life in great pain. He had always been in delicate health, suffering

even in his youth from migraine. Over the years, Pascal’s constant work took a toll

on his already fragile health.

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. An autopsy performed after his

death revealed grave problems with his stomach and other organs of his abdomen, along with damage to his brain.

Despite the autopsy, the cause of his poor health was never precisely determined, though speculation focuses

on tuberculosis, stomach cancer, or a combination of the two.

 The headaches which afflicted Pascal are generally attributed to his brain lesion.

PASCAL'S INVENTIONS AND DISCOVERIES HAVE BEEN INSTRUMENTAL TO DEVELOPMENTS IN

THE FIELDS OF GEOMETRY, PHYSICS AND COMPUTER SCIENCE. HIS EXPLORATION OF BINOMIAL COEFFICIENTS INFLUENCED SIR

ISAAC NEWTON, LEADING HIM TO UNCOVER HIS "GENERAL BINOMIAL THEOREM FOR

FRACTIONAL AND NEGATIVE POWERS."IN THE 1970S, THE PASCAL (PA) UNIT WAS

NAMED AFTER BLAISE PASCAL, IN HONOUR OF HIS CONTRIBUTIONS TO THE UNDERSTANDING

OF ATMOSPHERIC PRESSURE AND HOW IT COULD BE ESTIMATED IN TERMS OF WEIGHT.

THE PASCAL IS A UNIT OF PRESSURE THAT CONSTITUTES THE FORCE OF A SINGLE NEWTON

ACTING ON A SQUARE-METER SURFACE. IT IS MEASURED USING THE METER-KILOGRAM-SECOND

SYSTEM, WHICH RELIES ON AN EXTENDED VERSION OF THE METRIC SYSTEM TO CALCULATE PRESSURE.

IN 1972, COMPUTER SCIENTIST NICKLAUS WIRTH INVENTED A COMPUTER LANGUAGE AND INSISTED ON NAMING IT AFTER PASCAL. THIS WAS WIRTH'S WAY OF MEMORIALIZING PASCAL'S INVENTION OF THE PASCALINE, ONE OF THE EARLIEST FORMS OF

THE MODERN COMPUTER. PASCAL IS ALSO CREDITED WITH BUILDING THE FOUNDATION OF

PROBABILITY THEORY.