Empirical sciences prosecuted purely for their own sake, and without philosophic tendency are like a face without eyes.

The man who goes up in a balloon does not feel as if he were ascending; he only sees the earth sinking deeper below him.

There is in the world only the choice between loneliness and vulgarity. All young people should be taught now to put up with loneliness ... because the less man is compelled to come into contact with others, the better off he is.

It is a curious fact that in bad days we can very vividly recall the good time that is now no more; but that in good days, we have only a very cold and imperfect memory of the bad.

To buy books would be a good thing if we could also buy the time to read them; but the purchase of books is often mistaken for the assimilation and mastering of their contents.

We seldom speak of what we have but often of what we lack.

The bad thing about all religions is that, instead of being able to confess their allegorical nature, they have to conceal it.