Reason is feminine in nature; it can only give after it has received.

The faculty for remembering is not diminished in proportion to what one has learnt, just as little as the number of moulds in which you cast sand lessens its capacity for being cast in new moulds.

That arithmetic is the basest of all mental activities is proved by the fact that it is the only one that can be accomplished by a machine.

Solitude will be welcomed or endured or avoided, according as a man's personal value is large or small.

How is it possible that suffering that is neither my own nor of my concern should immediately affect me as though it were my own, and with such force that is moves me to action?

No one can transcend their own individuality.

The principle of contradiction establishes merely the agreement of concepts, but does not itself produce concepts.