The triumph of the Confederacy... would be a victory for the powers of evil which would give courage to the enemies of progress and damp the sprits of its friends all over the civilized world... [The American Civil War] is destined to be a turning point, for good or evil, of the course of human affairs.

The only freedom which deserves the name is that of pursuing our own good, in our own way, so long as we do not attempt to deprive others of theirs, or impede their efforts to obtain it.

Among the facts of the universe to be accounted for, it may be said, is Mind; and it is self evident that nothing can have produced Mind but Mind.

Over one's mind and over one's body the individual is sovereign.

Not only the grounds of the opinion are forgotten in the absence of discussion, but too often the meaning of the opinion itself... Instead of a vivid conception and a living belief, there remain only a few phrases retained by rote; or, if any part, the shell and husk only of the meaning is retained, the finer essence being lost.

The peculiar evil of silencing the expression of an opinion is, that it is robbing the human race; posterity as well as the existing generation; those who dissent from the opinion, still more than those who hold it. If the opinion is right, they are deprived of the opportunity of exchanging error for truth: if wrong, they lose, what is almost as great a benefit, the clearer perception and livelier impression of truth, produced by its collision with error.

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.