Reason now gazes above the realm of the dark but warm feelings as the Alpine peaks do above the clouds. They behold the sun more clearly and distinctly, but they are cold and unfruitful.

If we thought more for ourselves we would have very many more bad books and very many more good ones.

It is a sure evidence of a good book if it pleases us more and more as we grow older.

They do not think, therefore they are not.

A man is never more serious than when he praise himself.

If there were only turnips and potatoes in the world, someone would complain that plants grow the wrong way.

The great trick of regarding small departures from the truth as the truth itself - on which is founded the entire integral calculus - is also the basis of our witty speculations, where the whole thing would often collapse if we considered the departures with philosophical rigour.