Science, by itself, cannot supply us with an ethic. It can show us how to achieve a given end, and it may show us that some ends cannot be achieved.

The happy life is to an extraordinary extent the same as the good life.

When two great powers disagree about anything - it doesn't matter what - they must find a way to settle it somehow by arbitration or by negotiation, not by war or threat of war.

Inferences of Science and Common Sense differ from those of deductive logic and mathematics in a very important respect, namely, when the premises are true and the reasoning correct, the conclusion is only probable.

No man is liberated from fear who dare not see his place in the world as it is; no man can achieve the greatness of which he is capable until he has allowed himself to see his own littleness.

We must be skeptical even of our skepticism.

You find as you look around the world that every single bit of progress in humane feeling, every improvement in the criminal law, every step toward the diminution of war, every step toward better treatment of the colored races, or every mitigation of slavery, every moral progress that there has been in the world, has been consistently opposed by the organized churches of the world. I say quite deliberately that the christian religion, as organized in its churches, has been and still is the principle enemy of moral progress in the world.