When pressed for a sanction of motive Mill appeals to the Aristotelian principle that the individual can only realise his conception of himself through union with his fellows in society: to the social nature of man and his inability to find himself in any smaller sphere, or through devotion to any lesser end. "This firm foundation is that of the social feelings of mankind; the desire to be in unity with our fellow-creatures, which is already a powerful principle in human nature, and happily one of those which tend to become stronger, even without express inculcation, from the influences of advancing civilisation. The social state is at once so natural, so necessary, and so habitual to man, that, except in some unusual circumstances or by an effort of voluntary abstraction, he never conceives himself otherwise than as a member of a body; and this association is riveted more and more, as mankind are farther removed from the state of savage independence. Any condition, therefore, which is essential to a state of society, becomes more and more an inseparable part of every person's conception of the state of things which he is born into, and which is the destiny of a human being. In this way people grow up unable to conceive as possible to them a state of total disregard of other people's interests. They are under a necessity of conceiving themselves as at least abstaining from all the grosser injuries, and (if only for their own protection) living in a state of constant protest against them. They are also familiar with the fact of coöperating with others, and proposing to themselves a collective, not an individual, interest, as the aim (at least for the time being) of their actions. So long as they are coöperating, their ends are identified with those of others; there is at least a temporary feeling that the interests of others are their own interests. Not only does all strengthening of social ties, and all healthy growth of society, give to each individual a stronger personal interest in practically consulting the welfare of others; it also leads him to identify his feelings more and more with their good, or at least with an ever greater degree of practical consideration for it. He comes, as though instinctively, to be conscious of himself as a being who of course pays regard to others. The good of others becomes to him a thing naturally and necessarily to be attended to. This mode of conceiving ourselves and human life, as civilisation goes on, is felt to be more and more natural. Every step in political improvement renders it more so by removing the sources of opposition of interest, and levelling those inequalities of legal privilege between individuals or classes, owing to which there are large portions of mankind whose happiness it is still practicable to disregard. In an improving state of the human mind, the influences are constantly on the increase, which tend to generate in