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.

Miracles have no claim whatever to the character of historical facts and are wholly invalid as evidence of any revelation.

In all intellectual debates, both sides tend to be correct in what they affirm, and wrong in what they deny.

The strongest of all arguments against the interference of the public with purely personal conduct, is that when it does interfere, the odds are that it interferes wrongly, and in the wrong place.

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

On religion in particular, the time appears to me to have come, when it is a duty of all who, being qualified in point of knowledge, have, on mature consideration, satisfied themselves that the current opinions are not only false, but hurtful, to make their dissent known.

All silencing of discussion is an assumption of infallibility.