It must be granted that in every syllogism, considered as an argument to prove the conclusion, there is a petitio principii. When we say, All men are mortal Socrates is a man therefore Socrates is mortal; it is unanswerably urged by the adversaries of the syllogistic theory, that the proposition, Socrates is mortal.

Originality is the one thing which unoriginal minds cannot feel the use of.

If all mankind minus one were of one opinion, mankind would be no more justified in silencing that one person than he, if he had the power, would be justified in silencing mankind.

Society can and does execute its own mandates: and if it issues wrong mandates instead of right, or any mandates at all in things with it ought not to meddle, it practices a social tyranny more formidable than many kinds of political oppression, since, though not usually upheld by such extreme penalties, it leaves fewer means of escape, penetrating much more deeply into the details of life, and enslaving the soul itself.

It is not the feeling sure of a doctrine (be it what it may) which I call an assumption of infallibility. It is the undertaking to decide that question for others, without allowing them to hear what can be said on the contrary side. And I denounce and reprobate this pretension not the less, if put forth on the side of my most solemn convictions.

Most persons have but a very moderate capacity of happiness. Expecting...in marriage a far greater degree of happiness than they commonly find, and knowing not that the fault is in their own scanty capability of happiness.

I am not aware that any community has a right to force another to be civilized.