Show me a satisfied man, and I'll show you a failure.

During the youthful period of mankind's spiritual evolution human fantasy created gods in man's own image, who, by the operations of their will were supposed to determine, or at any rate to influence, the phenomenal world. Man sought to alter the disposition of these gods in his own favour by means of magic and prayer.

When you trip over love, it is easy to get up. But when you fall in love, it is impossible to stand again.

Blind belief in authority is the greatest enemy of truth.

I have never looked upon ease and happiness as ends in themselves. This ethical basis I call the ideal of the pigsty.

I believe that whatever we do or live for has its causality; it is good, however, that we cannot see through to it.

Belief in an external world independent of the perceiving subject is the basis of all natural science.