Poetry must have something in it that is barbaric, vast and wild.
Watch out for the fellow who talks about putting things in order! Putting things in order always means getting other people under your control.
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.
Patriotism is an ephemeral motive that scarcely ever outlasts the particular threat to society that aroused it.
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!
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.
The philosopher has never killed any priests, whereas the priest has killed a great many philosophers.
Sentences are like sharp nails, which force truth upon our memories.
What has not been examined impartially has not been well examined. Skepticism is therefore the first step toward truth.