Physics, owing to the simplicity of its subject matter, has reached a higher state of development than any other science.

It seems to me now that mathematics is capable of an artistic excellence as great as that of any music, perhaps greater; not because the pleasure it gives (although very pure) is comparable, either in intensity or in the number of people who feel it, to that of music, but because it gives in absolute perfection that combination, characteristic of great art, of godlike freedom, with the sense of inevitable destiny; because, in fact, it constructs an ideal world where everything is perfect and yet true.

If you question any candid person who is no longer young, he is very likely to tell you that, having tasted life in this world, he has no wish to begin again as a "new boy" in another.

Patriotism is the willingness to kill and be killed for trivial reasons.

A good man will never suspect his friends of shady actions: this is part of his goodness. A good man will never be suspected by the public of using his goodness to screen villains: this is part of his utility

There is something feeble, and a little contemptible, about a man who cannot face the perils of life without the help of comfortable myths. Almost inevitably some part of him is aware that they are myths and that he believes them only because they are comforting. But he dare not face this thought, and he therefore cannot carry his own reflection to any logical conclusion.

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.