"Liberty Consists In Doing What One Desires"
Context: John Stuart Mill bases the fifth chapter of his essay on liberty on two maxims: the first is that the individual is not accountable to society for those of his actions which concern only himself, and the second is that the individual is accountable to society for those actions which are prejudicial to others, indeed may for those actions be subjected to legal or social punishments. Mill applies these maxims to the concept of free trade, pointing out that restrictions on trade at least endanger, if not destroy, the liberty of the buyer. Any such infringement, or its danger, seems to Mill objectionable. The sale of poisons, he suggests, is an example of how the limits of police powers and the limits of liberty may be open to question. In his discussion he states that while it is the function of government to prevent crime, this preventive action is liable to abuse by officials. He goes on to say that it is a function of public authority to prevent accidents, and it is here that his definition of liberty occurs:
. . . it is a proper office of public authority to guard against accidents. If either a public officer or any one else saw a person attempting to cross a bridge which had been ascertained to be unsafe, and there were no time to warn him of his danger, they might seize him and turn him back without any real infringement of his liberty; for liberty consists in doing what one desires, and he does not desire to fall into the river. Nevertheless, when there is not a certainty, but only a danger of mischief, no one but the person himself can judge of the sufficiency of the motive which may prompt him to incur the risk; in this case, therefore, (unless he is a child, or delirious, or in some state of excitement or absorption incompatible with the full use of the reflecting faculty,) he ought, I conceive, to be only warned of the danger; not forcibly prevented from exposing himself to it. . . .