Life without pain has no meaning.

Just as the largest library, badly arranged, is not so useful as a very moderate one that is well arranged, so the greatest amount of knowledge, if not elaborated by our own thoughts, is worth much less than a far smaller volume that has been abundantly and repeatedly thought over.

No one knows what capacities for doing and suffering he has in himself, until something comes to rouse them to activity: just as in a pond of still water, lying there like a mirror, there is no sign of the roar and thunder with which it can leap from the precipice, and yet remain what it is; or again, rise high in the air as a fountain. When water is as cold as ice, you can have no idea of the latent warmth contained in it.

Nature shows that with the growth of intelligence comes increased capacity for pain, and it is only with the highest degree of intelligence that suffering reaches its supreme point.

This actual world of what is knowable, in which we are and which is in us, remains both the material and the limit of our consideration.

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

Style is what gives value and currency to thoughts.