No opinion has ever been too errant to become a creed.

The world that we must seek is a world in which the creative spirit is alive, in which life is an adventure full of joy and hope, based rather upon the impulse to construct than upon the desire to retain what we possess or to seize what is possessed by others.

Have no respect for the authority of others, for there are always contrary authorities to be found

Liberty is the right to do what I like; licence, the right to do what you like.

Fools and fanatics are always so certain of themselves.

Dogma demands authority, rather than intelligent thought, as the source of opinion; it requires persecution of heretics and hostility to unbelievers; it asks of its disciples that they should inhibit natural kindliness in favor of systematic hatred.

Protagoras did not know if the gods exist, but he held in any case they ought to be worshiped. Philosophy, according to him, had nothing edifying to teach, and for the survival of morals we must rely upon the thoughtlessness of the majority and their willingness to believe what they had been taught.