Human beings are not like sheep; and even sheep are not undistinguishably alike. A man cannot get a coat or a pair oboots to fit him, unless they are either made to his measure, or he has a whole warehouseful to choose from: and is it easier to fit him with a life than with a coat, or are human beings more like one another in their whole physical and spiritual conformation than in the shape of their feet? If it were only that people have diversities of taste, that is reason enough for not attempting to shape them all after one model.

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.

I know tolerably well what Ireland was, but have a very imperfect idea of what Ireland is.

The prevailing tendency to regard all the marked distinctions of human character as innate, and in the main indelible, and to ignore the irresistible proofs that by far the greater part of those differences, whether between individuals, races, or sexes are such as not only might but naturally would be produced by differences in circumstances, is one of the chief hinderances to the rational treatment of great social questions, and one of the greatest stumbling blocks to human improvement.

Popular opinions, on subjects not palpable to sense, are often true, but seldom or never the whole truth.

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. Each is the proper guardian of his own health, whether bodily, or mental or spiritual. Mankind are greater gainers by suffering each other to live as seems good to themselves, than by compelling each to live as seems good to the rest.

The perpetual obstacle to human advancement is custom.