Genius can only breathe freely in an atmosphere of freedom.

Life has a certain flavor for those who have fought and risked all that the sheltered and protected can never experience.

Education makes a man a more intelligent shoemaker, if that be his occupation, but not by teaching him how to make shoes; it does so by the mental exercise it gives, and the habits it impresses.

It's hardly possible to overstate the value, in the present state of human improvement, of placing human beings in contact with other persons dissimilar to themselves, and with modes of thought and action unlike those with which they are familiar. Such communication has always been... one of the primary sources of progress.

Not the violent conflict between parts of the truth, but the quiet suppression of half of it, is the formidable evil; there is always hope when people are forced to listen to both sides; it is when they attend to only one that errors harden into prejudices, and truth itself ceases to have the effect of truth, by being exaggerated into falsehood.

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.

A cultivated mind is one to which the fountains of knowledge have been opened, and which has been taught, in any tolerable degree, to exercise its faculties.