The course of the seasons is a piece of clockwork, with a cuckoo to call when it is spring.

Theologians always try to turn the Bible into a book without common sense.

There exists a species of transcendental ventriloquism by means of which men can be made to believe that something said on earth comes from Heaven.

The thoughts written on the walls of madhouses by their inmates might be worth publicizing.

Men still have to be governed by deception.

Prejudices are so to speak the mechanical instincts of men: through their prejudices they do without any effort many things they would find too difficult to think through to the point of resolving to do them.

I have often noticed that when people come to understand a mathematical proposition in some other way than that of the ordinary demonstration, they promptly say, "Oh, I see. That's how it must be." This is a sign that they explain it to themselves from within their own system.