The most perfect political community must be amongst those who are in the middle rank, and those states are best instituted wherein these are a larger and more respectable part, if possible, than both the other; or, if that cannot be, at least than either of them separate.
And this activity alone would seem to be loved for its own sake; for nothing arises from it apart from the contemplating, while from practical activities we gain more or less apart from the action. And happiness is thought to depend on leisure; for we are busy that we may have leisure, and make war that we may live in peace.
Since the branch of philosophy on which we are at present engaged differs from the others in not being a subject of merely intellectual interest — I mean we are not concerned to know what goodness essentially is, but how we are to become good men, for this alone gives the study its practical value — we must apply our minds to the solution of the problems of conduct.
One citizen differs from another, but the salvation of the community is the common business of them all. This community is the constitution; the virtue of the citizen must therefore be relative to the constitution of which he is a member.