ABSTRACT
A belief common to much ofboth recent political and legal theory and popular moral and political thought is that a necessary, though not sufficient, condition for the legal restriction of any activity is its being harmful. Furthermore, in what might loosely be called the liberal tradition, it is primarily the prevention ofharm to others which has been thought to be the proper concern of the law. Actions and practices which are not harmful, and for the liberal those where such harm as there is largely affects only the agent, should be tolerated. The classic statement of this view, of course, is that of J. S. Mill:
The object of this essay is to assert one very simple principle as entitled to govern absolutely the dealings of society with the individual in the way of compulsion and control, whether the means used be physical force in the form of legal penalties or the moral coercion of public opinion. That principle is that the sole end for which mankind are warranted, individually or collectively, in interfering with the liberty of action of any one of their number is self-protection. That the only purpose for which power can be rightfully exercised over a member of a civilised community, against his will, is to prevent harm to others. 1
As Mill makes clear, in this passage and elsewhere in On Liberty, his concern is not merely with legal prohibition but also with what he calls 'the moral coercion of public opinion' which makes his principle of broader relevance than the proper scope of law. However, despite its claimed simplicity, Mill's principle has been
subject to a variety of interpretations as to its meaning. One problem which has occasioned this variety of interpretations is Mill's conception of harm and its role in the application of his principle. The importance of this issue should be apparent, for if Mill's principle is to be of much practical use in identifying a range of conduct which should be tolerated, then there needs to be some uncontroversial way of distinguishing those actions and practices which are harmful from those which are not. In what follows I will suggest that there is no uncontroversial way in which such a distinction can be drawn and, therefore, any attempt to justify toleration which relies on such a supposedly agreed distinction is likely to be seriously defective. I begin with a brief consideration of this problem as it arises in Mill.
