If I go for the alternative which is false, then obviously I shall be in error; if I take the other side, then it is by... chance that I arrive at the truth, and I shall still be at fault.... In this incorrect use of free will may be found the privation which constitutes the essence of error.

Although my knowledge grows more and more, nevertheless I do not for that reason believe that it can ever be actually infinite, since it can never reach a point so high that it will be unable to attain any greater increase.

I hope that posterity will judge me kindly, not only as to the things which I have explained, but also to those which I have intentionally omitted so as to leave to others the pleasure of discovery.

In order to improve the mind, we ought less to learn, than to contemplate.

When writing about transcendental issues, be transcendentally clear.

Perfect numbers like perfect men are very rare.

The only thing that I know, is that I know nothing