Brevity: To say at once whatever is to be said.

Many things about our bodies would not seem to us so filthy and obscene if we did not have the idea of nobility in our heads.

The natural scientists of the previous age knew less than we do and believed they were very close to the goal: we have taken very great steps in its direction and now discover we are still very far away from it. With the most rational philosophers an increase in their knowledge is always attended by an increased conviction of their ignorance.

The fruits of philosophy are the important thing, not the philosophy itself. When we ask the time, we don't want to know how watches are made.

If another Messiah was born he could hardly do so much good as the printing-press.

Nothing reveals a man's character better than the kind of joke at which he takes offense.

To see every day how people get the name 'genius' just as the wood-lice in the cellar the name 'millipede'-not because they have that many feet, but because most people don't want to count to 14-this has had the result that I don't believe anyone any more without checking.