Aristotle's Politics (from around 350 B.C.E.) is presented as a follow-up to his Nichomachean Ethics (which we discussed in a previous episode). Actually, we're not sure in what order these were composed, and the Politics is internally repetitious enough that it is probably itself mashed together from different original sources; those that are into that kind of thing can read more about the troubles of interpreting the form of those of Aristotle's works that have reached us at Aristotle's Stanford Encyclopedia page.
The distinction between ethics and politics for Aristotle (as for Plato) is tenuous, as part of "virtue" is how one acts as a citizen (man being a political animal and all), and the form of government will define what citizenship entails. Aristotle thought that a person can only really achieve his potential (his telos) when in a well-structured society, and that society is a natural outgrowth of the human need for association. What makes for a well-structured society? Aristotle is a realist, unlike Plato (if you take Plato's Republic to be a serious political text and not just an allegorical account of the human soul; it's clear that Aristotle did take Plato's suggestions about education and ordering social classes seriously), so he recognizes that there's not one kind of government that will be the best of the available options for all peoples at all times and in all social situations, but he does think that we can examine the experience of the many city-states with different constitutions (a constitution is not necessarily a document; it's just Aristotle's way of referring to the arrangement of political offices) to come up with a plethora of insights into what makes a state work (i.e. fulfill its own telos). What's important overall is that the best rule, meaning those with good judgment, which for Aristotle amounts to a sense of justice.
A state needs first and foremost to be stable, meaning that in general, even a bad law is better kept in place, so as to give the citizens the habit of keeping orderly; the advantage gained by reform will not be likely to outweigh the disadvantage of the disorder brought about by the change. Aristotle was keenly aware of class struggle: if the rich (the few) are put in power (an oligarchy), they will exploit the poor, while if the poor (the many) are put in power (a democracy), they will likely fleece the rich. In either case, dissension is the likely result. While Aristotle thinks the ideal government would have an all-wise, all-benevolent monarch at its head, he thinks that in practice, monarchies tend to devolve into tyrannies, which he considers the worst of all possible governments, in that they don't promote the flourishing of the citizens, and again, they're not stable. Besides, in general, more heads are better than fewer, so long as all of those heads are wise, which Aristotle thinks is not likely given how difficult it is to attain wisdom/virtue.
Aristotle considers such questions as: Who should the citizenry include? (He disdained the mere artisans and believed that some people are naturally slaves.) Is it more important to have good laws or wise people deciding individual cases according to the law? (Really, you need both.) Is the active political life better than the contemplative, philosophical life? (These are both part of the human telos.) Should citizens play the flute? (No, they should have musical instruction, which like philosophy is training to flourish in a state of peace, but the flute is too hard and should be left to slaves and other riff-raff.)
Our assigned sections of this are:
Book 1, chapters 1,2
Book 4, 1-3
Book 5, 1,2
Book 6, 1-6
Book 7, 1-3, 13-15
Books 2 and 8 include his responses to the Republic, if you're interested, though we don't take those particular parts of Plato seriously enough to warrant covering this part of Aristotle in detail.