...the nonexistence of God makes more difference to some of us than to others. To me, it means that there is no absolute morality, that moralities are sets of social conventions devised by humans to satisfy their needs.

Many orthodox people speak as though it were the business of sceptics to disprove received dogmas rather than of dogmatists to prove them. This is, of course, a mistake.

The discipline in your life should be one determined by your own desires and your own needs, not put upon you by society or authority.

Men fear thought as they fear nothing else on earth - more than ruin, more even than death. Thought is subversive and revolutionary, destructive and terrible, thought is merciless to privilege, established institutions, and comfortable habits; thought is anarchic and lawless, indifferent to authority, careless of the well-tried wisdom of the ages. Thought looks into the pit of hell and is not afraid ... Thought is great and swift and free, the light of the world, and the chief glory of man.

What is matter? Never mind.

The sentiments of an adult are compounded of a kernel of instinct surrounded by a vast husk of education.

Moral progress has consisted in the main of protest against cruel customs, and of attempts to enlarge human sympathy.