I am not myself in any degree ashamed of having changed my opinions.

Organic life, we are told, has developed gradually from the protozoon to the philosopher, and this development, we are assured, is indubitably an advance. Unfortunately it is the philosopher, not the protozoon, who gives us this assurance.

When conscious activity is wholly concentrated on some one definite purpose, the ultimate result, for most people, is lack of balance accompanied by some form of nervous disorder.

Men have physical needs, and they have emotions. While physical needs are unsatisfied, they take first place; but when they are satisfied, emotions unconnected with them become important in deciding whether a man is to be happy or unhappy.

Both in thought and in feeling, even though time be real, to realise the unimportance of time is the gate of wisdom.

Mathematics, rightly viewed, possesses not only truth, but supreme beauty-a beauty cold and austere ... yet sublimely pure and capable of stern perfection such as only the greatest art can show.

You could live without the opera singer, but not without the services of the baker. On this ground you might say that the baker performs a greater service; but no lover of music would agree.