As a rule we disbelieve all the facts and theories for which we have no use.

I take it that no man is educated who has never dallied with the thought of suicide.

One hears of the mechanical equivalent of heat. What we now need to discover in the social realm is the moral equivalent of war: something heroic that will speak to men as universally as war does, and yet will be as compatible with their spiritual selves as war has proved itself to be incompatible.

Since you make evil or good by your own thoughts, it is your ruling of your thoughts which proves to be your principal concern.

No more fiendish punishment could be devised, were such a thing physically possible, than that one should be turned loose in society and remain absolutely unnoticed.

The greatest discovery of the 20th Century is that our attitude of mind determines our quality of life, not circumstances.

Despair lames most people, but it wakes others fully up.