Animals often strike us as passionate machines.

We can be absolutely certain only about things we do not understand.

Friendship Never explain -- your friends do not need it, and your enemies will not believe it anyway. A real friend never gets in your way, unless you happen to be on the way down. A friend is someone you can do nothing with and enjoy it. However much we guard ourselves against it, we tend to shape ourselves in the image others have of us. It is not so much the example of others we imitate, as the reflection of ourselves in their eyes and the echo of ourselves in their words.

There is nothing more explosive than a skilled population condemned to inaction. Such a population is likely to become a hotbed of extremism and intolerance, and be receptive to any proselytizing ideology, however absurd and vicious, which promises vast action.

It is the malady of our age that the young are so busy teaching us that they have no time left to learn.

The trouble is not chiefly that our universities are unfit for students but that many present-day students are unfit for universities.

Retribution often means that we eventually do to ourselves what we have done unto others.