50 Fun Facts About Blaise Pascal

In which French city was Blaise Pascal born in 1623?

His mother Antoinette Begon died when he was three, and in 1631 his father moved the family to Paris.

What was the profession of Pascal's father Étienne when he took the family to Rouen in 1639?

Étienne, an amateur mathematician and judge, decided to educate his children himself and never remarried.

At 12, Pascal rediscovered the first 32 propositions of which work on his own?

His father had tried to keep him from mathematics; after this he was given a copy of the book.

Pascal's Essay on Conics, written at 16, proved a theorem about a hexagon in a conic. What did he call it?

The three intersection points of opposite sides lie on a line now called the Pascal line; the work followed the ideas of Desargues.

Which philosopher was so unconvinced by the teenage Pascal's conics essay that he assumed his father wrote it?

Told otherwise by Mersenne, he grudgingly allowed that the demonstrations were better than the ancients' but that other matters 'would scarcely occur to a 16-year-old child'.

Why did the young Pascal build his mechanical calculator in 1642?

He was not yet 19; the machine, later called the Pascaline, could add and subtract.

How many Pascalines are known to have survived?

Four are in the Musée des Arts et Métiers in Paris and one in the Zwinger in Dresden; Pascal built about 20 finished machines over ten years.

Why did the Pascaline fail commercially?

It became little more than a toy and status symbol for the very rich across Europe.

Letters discovered in 1957 showed which German had drawn a working calculating clock twenty years before Pascal?

He described it in letters to Kepler in 1623 and 1624, which is why Pascal is called one of the first two inventors of the mechanical calculator.

With which mathematician did Pascal correspond in 1654, founding probability theory?

The problem was how two players stopping a game early should divide the stakes; the notion of expected value grew out of it.

Which gambling friend prompted the Pascal–Fermat correspondence?

Huygens later learned of the subject from their letters and wrote the first book on probability.

Who wrote the first book on probability after learning of the subject from the Pascal–Fermat letters?

Pascal and Fermat did not develop the field far themselves; de Moivre and Laplace carried it on later.

What did Pascal call the tabular arrangement of binomial coefficients that now bears his name?

His treatise on it was written in 1654 but published only in 1665, and it also contains an explicit statement of mathematical induction.

In China the triangle is named after which 13th-century mathematician?

In Iran it is Khayyam's triangle and in Italy Tartaglia's triangle, after the algebraist who published six rows in 1556.

What ailment did Pascal take as a heavenly sign to proceed with his 1658 study of the cycloid?

He finished his essay eight days later and announced a contest with prizes of 20 and 40 Spanish doubloons.

Which English architect sent Pascal a proof of the rectification of the cycloid during his contest?

Wallis published the proof crediting Wren, giving him priority; neither contest entry was judged adequate.

Whose barometer experiments, involving a tube of mercury inverted in a bowl, did Pascal build on in 1647?

Most scientists, including Descartes, still held that 'nature abhors a vacuum' and that an invisible plenum filled all space.

What did Pascal's 1647 work argue filled the space above the mercury in a barometer tube?

Descartes and the Aristotelians insisted on a plenum; Pascal replied that a hypothesis contradicted by a single phenomenon is thereby falsified.

Which mountain did Pascal's brother-in-law climb with a barometer in 1648 to test air pressure?

Pascal was too ill to climb it himself; Florin Périer found the mercury 26 inches high in town and only about 23 inches at the 1,460 m summit.

Pascal repeated the altitude experiment in Paris by carrying a barometer up which building?

The 50-metre climb dropped the mercury by two lines; he concluded that every seven fathoms of ascent lowered it by half a line.

What allegedly happened when Pascal filled a thin tube attached to a water cask to a great height?

It demonstrated that hydrostatic pressure depends on height difference, not on the weight of fluid.

Which two devices are listed among Pascal's inventions in fluid mechanics?

He proved that hydrostatic pressure depends on elevation difference rather than the weight of the fluid.

The pascal, the SI unit of pressure, is defined as what?

Weather reports use hectopascals, and standard sea-level pressure is about 1,013 hPa.

In which year did the General Conference on Weights and Measures adopt the name pascal for the SI pressure unit?

One hectopascal equals one millibar and one kilopascal equals one centibar.

Pascal introduced a primitive form of which casino game while searching for a perpetual motion machine?

The wheel was a by-product of his tinkering; his more lasting gambling legacy was probability theory.

Which Catholic movement, named by its detractors, did Pascal and sister Jacqueline join in 1646?

The Provincial Letters later attacked the Jesuits on the Jansenists' behalf, and Louis XIV suppressed the movement at Port-Royal in 1661.

Which convent did Jacqueline Pascal enter as a postulant in 1652, over her brother's objections?

Blaise feared abandonment as much as anything; she signed over her inheritance in return for a stipend.

Pascal's note recording his religious experience of 23 November 1654 begins with what word?

He sewed the 'Memorial' into his coat and moved it whenever he changed clothes; a servant found it by chance after his death.

Under what pseudonym did Pascal publish the Provincial Letters in 1656–57?

The 18 letters attacked Jesuit casuistry and so incensed Louis XIV that he ordered the book shredded and burned.

What Jesuit-favoured ethical method did the Provincial Letters attack as reasoning that excused moral laxity?

Their humour and satire influenced Voltaire and Rousseau, and they contain Pascal's apology for writing a long letter because he lacked time to write a short one.

What was the intended title of Pascal's unfinished defence of Christianity, published as the Pensées?

The scraps of paper found after his death first appeared in print in 1669; Will Durant called it 'the most eloquent book in French prose'.

Pascal wrote that man is 'the weakest in nature', a mere reed, but a reed of what kind?

Sainte-Beuve called one section of the Pensées the finest pages in the French language.

Pascal's wager says one should live as though God exists because the potential gain is what?

If God does not exist the believer loses only finite pleasures; the wager is called the first formal use of decision theory.

What was the original name of the section of the Pensées containing Pascal's wager?

It is a fideistic, probabilistic argument for belief in God.

What was Pascal's last major achievement, shortly before his death in 1662?

The carrosses à cinq sols ran on five fixed routes at a fixed fare and left even without passengers, principles later used to plan public transport.

What was the fixed fare of Pascal's carriage service, which gave it its name?

Pascal has been credited as the inventor of modern public transportation for the scheme.

How old was Pascal when he died in Paris in 1662?

His last words were 'May God never abandon me'; an autopsy revealed grave stomach damage and a brain lesion, but no firm cause was found.

In which Paris cemetery was Pascal buried?

He died on 19 August 1662, the morning after receiving extreme unction.

Which company announced a 'Pascal' graphics microarchitecture named for him in 2014?

A programming language also bears his name, and Blaise Pascal Chairs bring foreign scientists to the Île-de-France region.

What quality of hydrostatic pressure did Pascal prove?

The principle underlies the hydraulic press.

What ended Pascal's family's comfortable Paris income in 1638?

Étienne's worth fell from nearly 66,000 livres to under 7,300; he then had to flee Paris for opposing the cardinal's fiscal policies.

How was Étienne Pascal pardoned by Richelieu after fleeing Paris?

The children had been left with Madame Sainctot, a beauty with an infamous past who kept a glittering salon.

Which queen received one of Pascal's calculators as a gift?

Pascal referred to some 50 machines built to his design.

Pascal's De l'Esprit géométrique was originally written as a preface for what?

Unpublished for over a century, it argues that ideal method founds all propositions on already established truths.

Which mathematician's work on conic sections particularly inspired the teenage Pascal?

Pascal sent his resulting essay to Père Mersenne in Paris.

How old was Blaise Pascal when his mother, Antoinette Begon, died?

Pascal lost his mother at three; he was raised by his father Étienne, a judge and amateur mathematician, alongside sisters Gilberte and Jacqueline.

In Disney's Tangled, what kind of animal is the character named for Pascal?

Rapunzel's tiny sidekick shares the philosopher's name; the horse in the same film is Maximus.

Which Italian director made the biopic Blaise Pascal, first aired on television in 1971?

Rossellini made a series of historical films for television late in his career, including portraits of Socrates and Descartes as well as Pascal.

What are recorded as Pascal's last words, spoken in August 1662?

He died the morning after receiving extreme unction on 18 August 1662; an autopsy found stomach and brain damage but never settled the cause.

By what year had the last of Pascal's Paris carriage lines closed?

The carriages ran fixed routes at a fixed price and left even when empty, but never made money; the last line shut about 13 years after Pascal's death.