 Because an individual’s good is included in the good of community, the full realization of an individual’s rational powers is not something he can achieve or maintain on his own. It is hard, Aristotle says in Nicomachean Ethics IX.9, for a solitary person to be continuously active, but it is easier with others. To realize our powers fully we need at least a group of companions who share our interests and with whom we can cooperate to achieve our mutually recognized goals. In this kind of cooperative activity, we are parts of a larger enterprise, so that when others act, it is as though we are acting, too. In this way, these activities expand our conception of who “we” are, and they make the use of our powers more continuous and more stable. Examples listed by Aristotle include sailors on a ship, soldiers on an expedition, members of families, business relationships, religious associations, citizens of a political community, and colleagues engaged in contemplative activity. As Aristotle explains in Rhetoric II.4, if we and our cooperative partners do their parts responsibly, each will develop feelings of friendship for the others involved. In this way, successful cooperative activity transforms persons’ desires and motivations. Although we may have initiated activity for self-interested reasons, the psychological result is that we come to like our cooperative partners and to develop a concern for their good for their own sakes. This change, Aristotle indicates, is caused to occur in us. It is not chosen. Once bonds of friendship are formed, it is natural for us to exhibit the social virtues Aristotle describes in Nicomachean Ethics IV.6–8, which include generosity, friendliness, and mildness of temper. 