The key to every man is his thought.

The value of a college education is not the learning of many facts but the training of the mind to think.

It is hard to fight desire; but to control it is the sign of a reasonable man.

Now is no time to think of what you do not have. Think of what you can do with what there is.

Only when we realize that there is no eternal, unchanging truth or absolute truth can we arouse in ourselves a sense of intellectual responsibility.

Reading furnishes the mind only with materials of knowledge; it is thinking that makes what we read ours.

When we are tired, we are attacked by ideas we conquered long ago.

There are only two kinds of people, those who accept dogmas and know it, and those who accept dogmas and don't know it.