Blaise Pascal was one of the most important scholars of the 17th century. He was a great scientist, mathematician, and inventor, famous for many key breakthroughs. He was also a devoted Catholic and wrote what is considered to be one of the best apologetic works of his time.

But he wasn’t always a believer. After spending most of his life only nominally interested in religion, he had a dramatic conversion – and it was due to an incredible and dramatic mystical experience.

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Pascal was born in France in 1623. The second of three children, his mother died when he was just 3 years old. A few years later, his father moved their family to Paris.

Pascal’s intelligence was evident from a young age, so his father decided to personally educate him at home. And it paid off: when Pascal was just 16 years old, he was already making mathematical breakthroughs and engaging in academic discourse with professional mathematicians. By age 19, he had invented his own mechanical calculator, about 50 units of which he sold to various wealthy families in Europe. During his 20s and early 30s, Pascal did important work with mathematical probability and made important discoveries related to fluids and pressure.

In 1646, his father fell and broke his hip, a devastating injury in that time. The two doctors that worked with his father over the next few months happened to be devout Catholics (though they were a part of the small but growing Jansenist sect). Through their friendship and conversations with him, Pascal started to think seriously about religion for the first time in his life.

Many biographers call this his “first conversion.” It was mostly intellectual and did not last long. When his father died in 1651, he moved on from religion and entered what many call his “worldly period.” Soon after, his younger sister decided to join a convent, to which her third of their father’s estate was given. Since his older sister had already used her part as a dowry, 30-year-old Pascal was left with just his third of his father’s estate, without his parents, and with both of his sisters fully engaged in other vocations.

In other words, he was poor and alone. And that is when God entered his life in an amazing way.

It was November 23rd, 1654 and Pascal was at home alone. The sun was set and all was dark. He was most likely preparing for bed when, suddenly, at around 10:30pm, something supernatural happened. It’s not clear exactly what he saw, but the amazing mystical experience lasted for a full two hours. As soon as it was over, he grabbed a pen and paper and wrote down what was swirling through his head.

Here’s what he wrote:

The year of grace 1654,

Monday, 23 November, feast of St. Clement, pope and martyr, and others in the martyrology. Vigil of St. Chrysogonus, martyr, and others. From about half past ten at night until about half past midnight,

FIRE.

GOD of Abraham, GOD of Isaac, GOD of Jacob

not of the philosophers and of the learned.

Certitude. Certitude. Feeling. Joy. Peace.

GOD of Jesus Christ.

My God and your God.

Your GOD will be my God.

Forgetfulness of the world and of everything, except GOD.

He is only found by the ways taught in the Gospel.

Grandeur of the human soul.

Righteous Father, the world has not known you, but I have known you.

Joy, joy, joy, tears of joy.

I have departed from him:

They have forsaken me, the fount of living water.

My God, will you leave me?

Let me not be separated from him forever.

This is eternal life, that they know you, the one true God, and the one that you sent, Jesus Christ.

Jesus Christ.

Jesus Christ.

I left him; I fled him, renounced, crucified.

Let me never be separated from him.

He is only kept securely by the ways taught in the Gospel:

Renunciation, total and sweet.

Complete submission to Jesus Christ and to my director.

Eternally in joy for a day’s exercise on the earth.

May I not forget your words. Amen.

Wow! Whatever he saw, it sounds amazing.

He then took the piece of paper with the story and carefully sewed it into the inside of his jacket, which he kept with him the rest of his life. This was not discovered until after his death.

Unlike his first intellectual conversion, this conversion was of the heart – and it stuck. He mostly gave up his work in mathematics and devoted himself to theology and apologetics. A few years later, he published Provincial Letters, an attack on moral casuistry that became famous not only for its arguments, but also for its humor and effective use of satire.

In his mid-30s he started writing a comprehensive apologetic work with the working title “Defense of the Christian Religion.” But he became very sick and was unable to finish it. On August 18th, 1662, he fell into convulsions and received Anointing of the Sick. The next morning, he died at the age of 39. His last words? “May God never abandon me.”

The drafts and notes for his apologetic work were collected and published posthumously with the uninspired title “Thoughts of M. Pascal on religion, and on some other subjects,” better known by the title’s first word in the original French: Pensées. Despite being just a draft, it was an instant success, and remains today a classic of apologetics.

Do you know of another great scientist who converted to Catholicism? Tell the story in the comments!

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