general which affect others, be supposed amenable to social control. But a little reflection corrects the first impression, by showing that if the case is not strictly within the definition of individual liberty, yet the reasons on which the principle of individual liberty is grounded, are applicable to it. If people must be allowed, in whatever concerns only themselves, to act as seems best to themselves at their own peril, they must equally be free to consult with one another about what is fit to be so done; to exchange opinions, and give and receive suggestions. Whatever it is permitted to do, it must be permitted to advise to do. The question is doubtful, only when the instigator derives a personal benefit from his advice; when he makes it his occupation, for subsistence or pecuniary gain, to promote what society and the State consider to be an evil. Then, indeed, a new element of complication is introduced; namely the existence of classes of persons with an interest opposed to what is considered as the public weal, and whose mode of living is grounded on the counteraction of it. Ought this to be interfered with, or not? Fornication, for example, must be tolerated, and so must gambling; but should a person be free to be a pimp, or to keep a gambling-house? The case is one of those which lie on the exact boundary line between two principles, and it is not at once apparent to which of the two it properly belongs.