Every present state of a simple substance is a natural consequence of its preceding state, in such a way that its present is big with its future.

The main things which seem to me important on their own account, and not merely as means to other things, are knowledge, art, instinctive happiness, and relations of friendship or affection.

There's nothing I like less than bad arguments for a view that I hold dear.

Need is considered the cause why something came to be; but in truth it is often merely an effect of what has come to be.

The idea that all ideas are partly true, partly false, and partly meaningless is partly true, partly false and partly meaningless.

A mathematician may say anything he pleases, but a physicists must be at least partially sane.

Half of what I say is meaningless; but I say it so that the other half may reach you.

Anyone who conducts an argument by appealing to authority is not using his intelligence; he is just using his memory.

In religion and politics people's beliefs and convictions are in almost every case gotten at second-hand, and without examination, from authorities who have not themselves examined the questions at issue but have taken them at second-hand from other non-examiners, whose opinions about them were not worth a brass farthing.

Men who are unhappy, like men who sleep badly, are always proud of the fact.