One thing I certainly never was made for, and that is to put principles on and off at the dictation of a party, as a lackey changes his livery at his master's command.

Education is an organic necessity of a human being.

You need not tell all the truth, unless to those who have a right to know it; but let all you tell be truth.

Knowledge is but an instrument, which the profligate and the flagitious may use as well as the brave and the just.

Knowledge is a mimic creation.

Do not think of knocking out another person's brains because he differs in opinion from you. It would be as rational to knock yourself on the head because you differ from yourself ten years ago.

Scientific truth is marvelous, but moral truth is divine and whoever breathes its air and walks by its light has found the lost paradise.