If opponents of all important truths do not exist, it is indispensable to imagine them and supply them with the strongest arguments which the most skillful devil's advocate can conjure up.

The duty of man is the same in respect to his own nature as in respect to the nature of all other things, namely not to follow it but to amend it.

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.

We have a right, also, in various ways, to act upon our unfavorable opinion of anyone, not to the oppression of his individuality, but in the exercise of ours.

All errors which a man is likely to commit against advice are far outweighed by the evil of allowing others to constrain him for his good.

There is an imaginary circle drawn around every human being, over which no government should be able to step.

Any participation, even in the smallest public function, is useful.