Ordinary people merely think how they shall 'spend' their time; a man of talent tries to 'use' it.

It is most important to allow the brain the full measure of sleep which is required to restore it; for sleep is to a man's whole nature what winding up is to a clock.

Truth that is naked is the most beautiful, and the simpler its expression the deeper is the impression it makes.

To form a judgment intuitively is the privilege of few; authority and example lead the rest of the world. They see with the eyes of others, they hear with the ears of others. Therefore it is very easy to think as all the world now think; but to think as all the world will think thirty years hence is not in the power of every one.

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

Our moral virtues benefit mainly other people; intellectual virtues, on the other hand, benefit primarily ourselves; therefore the former make us universally popular, the latter unpopular.

A man finds himself, to his great astonishment, suddenly existing, after thousands and thousands of years of non-existence: he lives for a little while; and then, again, comes an equally long period when he must exist no more. The heart rebels against this, and feels that it cannot be true.