There is nothing to be learned from the second kick of a mule.

In America-as elsewhere-free speech is confined to the dead.

I do love compliments, yet I'm often embarrassed to say what I think to the person when I get a compliment. I so often feel that they have not gone far enough.

As a rule we develop a borrowed European idea forward, and ... Europe develops a borrowed American idea backwards.

Religion consists in a set of things which the average man thinks he believes and wishes he was certain of.

I have never taken any exercise, except sleeping and resting, and I never intend to take any. Exercise is loathsome. And it cannot be any benefit when you are tired; and I was always tired.

You cannot have a theory without principles. Principles is another name for prejudices.