The world's greatest thinkers have often been amateurs; for high thinking is the outcome of fine and independent living, and for that a professional chair offers no special opportunities.

The relation of the individual person to the species he belongs to is the most intimate of all relations.

Heroes exterminate each other for the benefit of people who are not heroes.

The romantic embrace can only be compared with music and with prayer.

The mathematician has reached the highest rung on the ladder of human thought.

Jealousy, that dragon which slays love under the pretence of keeping it alive.

The place where optimism most flourishes is the lunatic asylum.