There are many truths of which the full meaning cannot be realized until personal experience has brought it home.

Genius can only breathe freely in an atmosphere of freedom.

Bad men need nothing more to compass their ends, than that good men should look on and do nothing.

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.

Liberty consists in doing what one desires.

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.

The maxim is, that whatever can be affirmed (or denied) of a class, may be affirmed (or denied) of everything included in the class. This axiom, supposed to be the basis of the syllogistic theory, is termed by logicians the dictum de omni et nullo.