Pascal today means a unit of pressure, a computer language, a law in fluid mechanics, and an array of numbers with certain properties.

Few who use his name in these ways know that Blaise Pascal was also a devout Christian and a profound apologist for his faith.

In 1623, Pascal was born into a world that had recently seen the Reformation, the Counter Reformation, and the beginnings of modern science. The Thirty Years War began five years before Pascal's birth, and he was ten when Galileo was forced to recant his teaching of the Copernican system.

Studying under his father, a civil servant, the precocious Pascal first displayed his talents at 16 with his "mystic hexagon" theorem, noting special qualities of a hexagon inscribed in a circle. This he followed with a book on geometry that some contemporary mathematicians refused to believe a teenager could have written.

At 19, he invented the distant ancestor of the modern computer—a calculating machine. Later, as he worked out answers to some friends' questions about gambling, the young genius founded probability theory.

Pascal added the physical sciences to his repertoire with experiments that expanded human knowledge of atmospheric pressure and the equilibrium of fluids. He was inspired to investigate these things by the invention of the barometer by a student of Galileo.

Pascal observed that mercury rises only thirty inches in a closed tube and saw that the space above the mercury challenged the old Aristotelian idea that "nature abhors a vacuum." His experiments on this phenomenon led him to conclude that a vacuum really did exist.

In defending this idea, he distinguished between the methods of science and those of theology. In the latter, said Pascal, tradition is the appropriate route to knowledge: we can't discover God scientifically. But neither can we learn from tradition how high a fluid will rise.

Indeed, he concluded, we should pity the blindness of those who bring authority alone as proof in physical matters, instead of reasoning or experiments; and we should abhor the wickedness of others who make use of reasoning alone in theology, instead of the authority of Scripture and the Fathers.

The night of fire

Pascal was on his way to a brilliant career as a mathematician and scientist when something more important intervened.

In 1646, after his father Etienne suffered a fall and was healed by the medical ministrations of two devout doctors, Blaise joined other members of his family in identifying with the Jansenist movement.


Cornelius Jansen, Bishop of Ypres, had written a book on the theology of St. Augustine, which presented a rigorous view of Christianity. Its emphasis on predestination, the severity of sin, and complete dependence on God's grace seem at first glance close to Calvinism.

Nevertheless, the Jansenists intended to be loyal members of the Roman Catholic Church, and they followed Catholic teachings about church, ministry, and sacraments.

Pascal was not, however, influenced by doctrinal arguments alone. On the night of November 23, 1654, he had a powerful religious experience. He scribbled down a hasty account in what has been called "Pascal's amulet," which he carried in the lining of his coat until his death. Its words set out the heart of the faith he would defend:


God of Abraham, God of Isaac, God of Jacob, not of the philosophers and savants
Certitude. Certitude. Feeling. Joy. Peace.
God of Jesus Christ.

Forgetfulness of the world and of everything except God
He is to be found only in the ways taught in the Gospel


This is life eternal, that they might know Thee, the only true God,
and Jesus Christ whom Thou hast sent

This "night of fire" had a profound impact. Pascal did not, however, see it as a private revelation that replaced or took precedence over the revelation to which Scripture bears witness.

It was an experience of the God of Israel, the One revealed in Christ. In his arguments for the truth of Christianity, Pascal never mentioned the night of fire: His "amulet" was found only after his death.

The Jansenists' strict views of Christian discipline and human incapacity to contribute to salvation set them at odds with the powerful Jesuits. Pascal's first theological writings, the Provincial Letters, were devastating attacks on the principles and policies of that order.

Pascal's most important contribution to Christian thought is the Pensées, the book that he was never able actually to write. It is a mark of Pascal's genius that his preparatory material could become such a classic.

Scholars have tried to reconstruct the work that Pascal projected. He was going to show first the wretchedness of humanity without God, and then the blessedness that is possible with the God who is known in Christ. This is a traditional approach, but Pascal's brilliance appears in the specific "thoughts" with which he intended to make these arguments.


"Only an occupation"

It is not true, as is sometimes said, that Pascal gave up mathematics after attaining his newfound faith. But during the last part of his life, he devoted himself to religious concerns, saying to his friend mathematician Pierre Fermat that geometry was "only an occupation," a dabbling in mundane things that pale in comparison to God's plan for the salvation of human souls.

We might expect Pascal to have much to say about relationships between science and religion, and perhaps to draw arguments from nature to demonstrate the truth of religion, as Newton and others would later do. But for Pascal, there is no way of knowing the true God apart from revelation—he found the argument from design unconvincing.

Those who seek God through nature, Pascal insisted in his Pensées, "either find no light to satisfy them, or contrive to find a way of knowing Him and serving Him without a mediator."

To Pascal, however, God is decidedly not absent in his world. Pascal reproached Descartes for what he saw as an effective deism, saying, "I cannot forgive Descartes. He would gladly have left God out of his whole philosophy. But he could not help making Him give one flip to set the world in motion. After that he had no more use for God."

What Pascal objected to was a natural theology that hinged on visible proofs. God is hidden—an idea that runs throughout the Pensées. Pascal argued with reference to Isaiah 45:15 ("Verily thou art a God that hidest thyself, O God of Israel, the Saviour" [KJV]) that what our eyes see in nature reveals "neither a total absence nor a manifest presence of the divine, but the presence of a God who conceals Himself."

The objection was prophetic. The natural theology of Newton and others led later generations to deism—the belief in a "clockmaker God" who creates the world but is not actively involved after that.

He bet his life on God

Though elsewhere he drew a sharp line between science and theology, Pascal's work on probability does lie behind his famous "wager." Either God exists or he does not, Pascal writes, and you must bet one way or another. If God exists, you could gain or lose infinite happiness. If God does not exist, then you could lose at most finite pleasure. "If you win, you win everything; if you lose, you lose nothing. Do not hesitate, then; gamble on His existence."

We may read in Pascal's life the signs of a man who bet his life on God. Compassionate as well as brilliant, he created the first public transportation system in Paris for the benefit of the poor. And in his own last illness, he gave his home over to a poor family stricken by smallpox.


In the end, Pascal left an example not only of how to think about Christianity, but also of how to live as a Christian.

George Murphy is adjunct professor at Trinity Lutheran Seminary in Columbus, Ohio, and pastoral associate at St. Paul's Episcopal Church, Akron, Ohio. His academic training is in both physics and theology.