“It is very important not to mistake hemlock for parsley, but to believe or not believe in God is not important at all.”

Scepticism is the first step toward truth.

Are we not madder than those first inhabitants of the plain of Sennar? We know that the distance separating the earth from the sky is infinite, and yet we do not stop building our tower.

I discuss with myself questions of politics, love, taste, or philosophy. I let my mind rove wantonly, give it free rein to followany idea, wise or mad that may present itself. My ideas are my harlots.

When one compares the talents one has with those of a Leibniz , one is tempted to throw away one’s books and go die quietly in the dark of some forgotten corner.

In order to shake a hypothesis, it is sometimes not necessary to do anything more than push it as far as it will go.

In general, children, like men, and men, like children, prefer entertainment to education.

To describe women, the pen should be dipped in the humid colors of the rainbow, and the paper dried with the dust gathered from the wings of a butterfly.

Although a man may wear fine clothing, if he lives peacefully; and is good, self-possessed, has faith and is pure; and if he does not hurt any living being, he is a holy man.

Only a very bad theologian would confuse the certainty that follows revelation with the truths that are revealed. They are entirely different things.

If you want me to believe in God, you must make me touch him.

All abstract sciences are nothing but the study of relations between signs.

No man has received from nature the right to give orders to others. Freedom is a gift from heaven, and every individual of the same species has the right to enjoy it as soon as he is in enjoyment of his reason.

Evil always turns up in this world through some genius or other.

Morals are in all countries the result of legislation and government; they are not African or Asian or European: they are good or bad.

One may demand of me that I should seek truth, but not that I should find it.

Every man has his dignity. I’m willing to forget mine, but at my own discretion and not when someone else tells me to.