Collective wisdom, alas, is no adequate substitute for the intelligence of individuals. Individuals who opposed received opinions have been the source of all progress, both moral and intellectual. They have been unpopular, as was natural.

The search for something permanent is one of the deepest of the instincts leading men to philosophy.

Public opinion is always more tyrannical towards those who obviously fear it than towards those who feel indifferent to it.

All forms of fear produce fatigue.

When the state intervenes to insure the indoctrination of some doctrine, it does so because there is no conclusive evidence in favor of that doctrine.

To teach how to live without certainty and yet without being paralysed by hesitation is perhaps the chief thing that philosophy, in our age, can do for those who study it.

The reason is, and by rights ought to be, slave to the emotions.