Tolerably early in life I discovered that one of the unpardonable sins, in the eyes of most people, is for a man to go about unlabeled. The world regards such a person as the police do an unmuzzled dog.

There is no alleviation for the sufferings of mankind except veracity of thought and of action, and the resolute facing of the world as it is when the garment of make-believe by which pious hands have hidden its uglier features is stripped off.

If a man cannot do brain work without stimulants of any kind, he had better turn to hand work it is an indication on Nature's part that she did not mean him to be a head worker.

Every great advance in natural knowledge has involved the absolute rejection of authority.

The method of scientific investigation is nothing but the expression of the necessary mode of working of the human mind.

I would rather be the offspring of two apes than be a man and afraid to face the truth.

No one can help another very much in these crises of life; but love and sympathy count for something.