The pupil who is never required to do what he cannot do, never does what he can do.

The most cogent reason for restricting the interference of government is the great evil of adding unnecessarily to its power.

The ne plus ultra of wickedness ... is embodied in what is commonly presented to mankind as the creed of Christianity.

Ask yourself whether you are happy, and you cease to be so.

Truths are known to us in two ways: some are known directly, and of themselves; some through the medium of other truths. The former are the subject of Intuition, or Consciousness; the latter, of Inference; the latter of Inference. The truths known by Intuition are the original premisses, from which all others are inferred.

Whatever crushes individuality is despotism.

To discover to the world something which deeply concerns it, and of which it was previously ignorant; to prove to it that it had been mistaken on some vital point of temporal or spiritual interest, is as important a service as a human being can render to his fellow creatures.