This chapter carries forward the theme of its predecessor, by distinguishing three ‘correct’ constitutions and three ‘deviations’. The three correct kinds aim at the common interest: kingship, aristocracy, ‘polity’; the three others aim at the sectional interest of the rulers: tyranny, oligarchy, democracy. In each set the first type is the rule of one, the second the rule of a few, and the third the rule of the many. These distinctions are somewhat rough-and-ready, as Aristotle himself recognizes in the next chapter.
1279a22 Having drawn these distinctions we must next consider what constitutions there are and how many. We begin with those that are correct, since when these have been defined it will be easy to see the deviations. As we have seen, ‘constitution’ and ‘citizen-body’ mean the same thing, and the citizen-body is the sovereign power in states. Sovereignty necessarily resides either in one man, or in a few, or in the many. Whenever the one, the few, or the many rule with a view to the common good, these constitutions must be correct; but if they look to the private advantage, be it of the one or the few or the mass, they are deviations. For either we must say that those who do not participate are not citizens, or they must share in the benefit.1
1279a32 The usual names for right constitutions are as follows: (a) Monarchy2 aiming at the common interest: kingship, (b) Rule of more than one man but only a few: aristocracy (so called either because the best men rule or because it aims at what is best for the state and all its members).3 (c) Political control exercised by the mass of the populace in the common interest: polity. This is the name common to all constitutions.4 It is reasonable to use this term, because, while it is possible for one man or a few to be outstanding in point of virtue, it is difficult for a larger number to reach a high standard in all forms of virtue – with the conspicuous exception of military virtue, which is found in a great many people. And that is why in this constitution the defensive element is the most sovereign body, and those who share in the constitution are those who bear arms.
1279b4 The corresponding deviations are: from kingship, tyranny; from aristocracy, oligarchy; from polity, democracy. For tyranny is monarchy2 for the benefit of the monarch, oligarchy for the benefit of the men of means, democracy for the benefit of the men without means. None of the three aims to be of profit to the common interest.