Men fear thought as they fear nothing else on earth - more than ruin, more even than death.

Man is a rational animal – so at least I have been told. Throughout a long life, I have looked diligently for evidence in favour of this statement, but so far I have not had the good fortune to come across it, though I have searched in many countries spread over three continents.

It is no credit to the orthodox that they do not now believe all the absurdities that were believed 150 years ago. The gradual emasculation of the Christian doctrine has been effected in spite of the most vigorous resistance, and solely as the result of the onslaughts of freethinkers.

Love should be a tree whose roots are deep in the earth, but whose branches extend into heaven.

It is the things for which there is no evidence that are believed with passion.

Without civic morality communities perish; without personal morality their survival has no value.

The practice of inhibiting impulses, which is to a great extent necessary to civilized life, makes mistakes easier, by preventing experience of the actions to which a desire would otherwise lead, and by often causing the inhibited impulses themselves to be unnoticed or quickly forgotten.