Thinkers

Blaise Pascal

Early Modern · Europe · 1623 to 1662

French mathematician and writer who reflected on human weakness. He argued that betting on faith is reasonable when certainty is out of reach.

What it is

Blaise Pascal (1623 to 1662) was a French mathematician, scientist and religious thinker whose posthumous Pensées defend Christianity, and who proposed the wager, an argument that belief in God is the wise bet. He was a pioneer of probability theory, he made lasting contributions to the study of air pressure and the vacuum, although he published no philosophical work in his lifetime.

He was born in Clermont, now Clermont-Ferrand, on 19 June 1623, and died in Paris on 19 August 1662, at the age of thirty-nine. His religious life was shaped by Jansenism and by the convent of Port-Royal in Paris.

The main ideas

• The Pensées. After his death, friends published a notebook in which he had drafted ideas for a planned defence of Christianity. It is unfinished, which is why its pieces are called thoughts.
• The wager. The best-known passage is the argument that, since we cannot settle by reason whether God exists, it is wiser to bet that God does. If one wins, the gain is everything, and if one loses, little is lost.
• Between misery and grandeur. He saw human beings as caught between misery and greatness, and held that people find consolation for their misery in religion.
• Reason and the heart. In his thought, reason is not the only way to know. There is also what he called the heart, and both are needed.
• The Provincial Letters. A satirical attack on the casuistry of the Jesuits and a defence of Jansenism, written for a general reader.
• Chance and probability. In a correspondence with Pierre Fermat he worked on how to calculate the odds in gambling, and so helped to found probability theory.
• Pressure and the vacuum. He did experimental and theoretical work on atmospheric pressure, hydraulics and the existence of the vacuum.

What it looks like in practice

Picture someone who cannot decide whether to take a religious claim seriously, and who knows that no argument is going to settle it. Pascal's wager invites them to compare the two risks: what they lose if they live as though it is true and it is not, against what they lose if they live as though it is false and it is true. This is an illustration of the argument, not a passage from the Pensées.

Books and moments

• The Provincial Letters made him famous as a writer.
• The Pensées (first published in 1670) are the notes for his planned defence of Christianity.
• The correspondence with Fermat on probability is among the founding episodes of that field.

Questions and criticism

• Is the wager a good argument? It treats belief as a bet. It is fair to ask whether belief can be chosen that way, and whether it is the kind of belief that religion asks for.
• Faith before reason? Some readers call him a fideist, one who puts faith above reason. Others stress that he valued reason and used it against his opponents.
• An unfinished book. The Pensées were never put in order, and readers disagree about how they were meant to fit together.

Close neighbours

The page on theism describes the family of views he defended.

Written by epchē in our own words, and checked against independent sources on 9 October 2026. The sources are listed below.

Where to start reading

Books by Blaise Pascal or about them, from the easiest way in to the harder ones.

All the books, by tradition

Who they connect to

Influenced

• Søren Kierkegaard · Kierkegaard read Pascal and shared his sense of the limits of reason in matters of faith.
• William James · James discusses Pascal's wager in The Will to Believe when defending faith under uncertainty.

Influenced by

• Augustine of Hippo · Pascal's view of human nature as fallen and dependent on grace comes from Augustine through the Jansenists.
• Michel de Montaigne · Pascal read the Essays closely, often arguing with them.

Reacted against

• René Descartes · Pascal called Descartes' philosophy useless and uncertain and put the heart's reasons beside those of reason.

Other Early Modern thinkers

• Hugo Grotius · 1583 to 1645
• Thomas Hobbes · 1588 to 1679
• Mary Astell · 1666 to 1731
• Giambattista Vico · 1668 to 1744

Sources we used

• Blaise Pascal · Stanford Encyclopedia of Philosophy, read on 9 October 2026
• Pascal, Blaise · Internet Encyclopedia of Philosophy, read on 9 October 2026