Five percent of the people think; ten percent of the people think they think; and the other eighty-five percent would rather die than think.

Our greatest weakness lies in giving up.

A good idea is never lost. Even though its originator or possessor may die, it will someday be reborn in the mind of another.

A diamond is a piece of coal that stuck to the job

My mind is incapable of conceiving such a thing as a soul. I may be in error, and man may have a soul; but I simply do not believe it.

The man who doesn’t make up his mind to cultivate the habit of thinking misses the greatest pleasure in life.

The perils of overwork are slight compared with the dangers of inactivity.