“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.”

He whom we call a gentleman is no longer the man of Nature.

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

I feel, I think, I judge; therefore, a part of organized matter like me is capable of feeling, thinking, and judging.

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

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

The best mannered people make the most absurd lovers.

Instinct guides the animal better than the man. In the animal it is pure, in man it is led astray by his reason and intelligence.

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

We are constantly railing against the passions; we ascribe to them all of man’s afflictions, and we forget that they are also the source of all his pleasures.

Disturbances in society are never more fearful than when those who are stirring up the trouble can use the pretext of religion to mask their true designs.

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

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.

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.

There is no kind of harassment that a man may not inflict on a woman with impunity in civilized societies.

Distance is a great promoter of admiration.

When superstition is allowed to perform the task of old age in dulling the human temperament, we can say goodbye to all excellence in poetry, in painting, and in music.