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

The God of the Christians is a father who makes much of his apples, and very little of his children.

The philosopher has never killed any priests, whereas the priest has killed a great many philosophers.

Our observation of nature must be diligent, our reflection profound, and our experiments exact. We rarely see these three means combined; and for this reason, creative geniuses are not common.

Skepticism is the first step on the road to philosophy.

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

The best mannered people make the most absurd lovers.

The possibility of divorce renders both marriage partners stricter in their observance of the duties they owe to each other. Divorces help to improve morals and to increase the population.

Poetry must have something in it that is barbaric, vast and wild.

Gratitude is a burden, and every burden is made to be shaken off.

We are far more liable to catch the vices than the virtues of our associates.

Sentences are like sharp nails, which force truth upon our memories.

The blood of Jesus Christ can cover a multitude of sins, it seems to me.

The best doctor is the one you run to and can't find.

There is no moral precept that does not have something inconvenient about 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.

The first step towards philosophy is incredulity.

No man has received from nature the right to command his fellow human beings.

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

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

From fanaticism to barbarism is only one step.

Pithy sentences are like sharp nails which force truth upon our memory.

There is no good father who would want to resemble our Heavenly Father.

You have to make it happen.

Watch out for the fellow who talks about putting things in order! Putting things in order always means getting other people under your control.

Power acquired by violence is only a usurpation, and lasts only as long as the force of him who commands prevails over that of those who obey.

His hands would plait the priest's guts, if he had no rope, to strangle kings.

There are three principal means of acquiring knowledge... observation of nature, reflection, and experimentation. Observation collects facts; reflection combines them; experimentation verifies the result of that combination.

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

My ideas are my whores.

We swallow greedily any lie that flatters us, but we sip only little by little at a truth we find bitter.

It is not human nature we should accuse but the despicable conventions that pervert it.

The general interest of the masses might take the place of the insight of genius if it were allowed freedom of action.

Justice is the first virtue of those who command, and stops the complaints of those who obey.

We are all instruments endowed with feeling and memory. Our senses are so many strings that are struck by surrounding objects and that also frequently strike themselves.

Gaiety is a quality of ordinary men. Genius always presupposes some disorder in the machine.

If there is one realm in which it is essential to be sublime, it is in wickedness. You spit on a petty thief, but you can't deny a kind of respect for the great criminal.

Only passions, great passions can elevate the soul to great things.

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

There is only one passion, the passion for happiness.

To attempt the destruction of our passions is the height of folly. What a noble aim is that of the zealot who tortures himself like a madman in order to desire nothing, love nothing, feel nothing, and who, if he succeeded, would end up a complete monster!

Good music is very close to primitive language.

People praise virtue, but they hate it, they run away from it. It freezes you to death, and in this world you've got to keep your feet warm.

It is said that desire is a product of the will, but the converse is in fact true: will is a product of desire.

When science, art, literature, and philosophy are simply the manifestation of personality they are on a level where glorious and dazzling achievements are possible, which can make a man's name live for thousands of years.

Genius is present in every age, but the men carrying it within them remain benumbed unless extraordinary events occur to heat up and melt the mass so that it flows forth.

One declaims endlessly against the passions; one imputes all of man's suffering to them. One forgets that they are also the source of all his pleasures.

Man will never be free until the last king is strangled with the entrails of the last priest.

There are things I can't force. I must adjust. There are times when the greatest change needed is a change of my viewpoint.