Aristotle, Nicomachean Ethics
H. Rackham, Ed.

The mutual rights of parents and children are not the same as those between brothers; the obligations of members of a comradeship not the same as those of fellow-citizens; and similarly with the other forms of friendship. [3] Injustice therefore also is differently constituted in each of these relationships: wrong is increasingly serious in proportion as it is done to a nearer friend. For example, it is more shocking to defraud a comrade of money than a fellow-citizen; or to refuse aid to a brother than to do so to a stranger; or to strike one's father than to strike anybody else. Similarly it is natural that the claims of justice also should increase with the nearness of the friendship, since friendship and justice exist between the same persons and are co-extensive in range. [4]

But all associations are parts as it were of the association of the State. Travellers for instance associate together for some advantage, namely to procure some of their necessary supplies. But the political association too, it is believed, was originally formed, and continues to be maintained, for the advantage of its members: the aim of lawgivers is the good of the community, and justice is sometimes defined as that which is to the common advantage. [5] Thus the other associations aim at some particular advantage; for example sailors combine to seek the profits of seafaring in the way of trade or the like, comrades in arms the gains of warfare, their aim being either plunder, or victory over the enemy or the capture of a city¹; and similarly the members of a tribe or parish² [And some associations appear to be formed for the sake of pleasure,