Do not use power to suppress opinions you think pernicious, for if you do the opinions will suppress you.

It is a waste of energy to be angry with a man who behaves badly, just as it is to be angry with a car that won't go.

Logic must no more admit a unicorn than zoology can.

Broadly speaking, we are in the middle of a race between human skill as a means and human folly as an end.

One's work is never so bad as it appears on bad days, nor so good as it appears on good days.

There may be no good reasons for very many opinions that are held with passion.

All definite knowledge - so I should contend - belongs to science; all dogma as to what surpasses definite knowledge belongs to theology. But between theology and science there is a No Man's Land, exposed to attack by both sides; this No Man's Land is philosophy.