I argue, therefore, that voluntary bodies are entitled outside the realm where their ideas and conduct are intended directly to alter the law, or to arrest the continuity of general social habits, to believe what they please and to practise what they please. This would not permit a body of burglars to take over from Proudhon the principle that property is theft and assume their right to restore it to themselves; but it would justify, to take the case of principles I personally abhor, a society of Mormons practising polygamy in a society like that of the United States. Let me turn from this to the political field. I take first the question of the right of the state to control freedom of association in the industrial sphere. Practically speaking, the question reduces itself to one of whether the state is justified in limiting the power of a trade union, or of a combination of trade unions to call out its members on strike. I want to put on one side the technical juristic questions involved and to discover, if I can, the justice of the general principles which underlie the problem. These are, I think, broadly four in number. It is argued that the state has a right to prohibit a general strike on the ground that this is an attempt to coerce the government either directly, by making it introduce legislation which it would not otherwise do, or indirectly, by inflicting such hardship on the community that public opinion forces the government to act. It is said, secondly, that the state is entitled to prohibit those whom it directly employs, for example postmen, from either going on strike, or affiliating themselves with any organization the nature of which may compromise the neutrality of the government. It is said, thirdly, that certain industries, railways, for example, or electricity supply, are so vital to the community that continuity of service in them is the law of their being, and that, therefore, the right to strike can be legitimately denied to those engaged in them. It is argued, fourthly, that a limitation upon the purposes of trade unions, so that they are confined within their proper industrial sphere, is also justified.