 In the Nicomachean Ethics Aristotle describes his subject matter as ‘political science’, which he characterizes as the most authoritative science. It prescribes which sciences are to be studied in the city-state, and the others — such as military science, household management, and rhetoric — fall under its authority. Since it governs the other practical sciences, their ends serve as means to its end, which is nothing less than the human good. “Even if the end is the same for an individual and for a city-state, that of the city-state seems at any rate greater and more complete to attain and preserve. For although it is worthy to attain it for only an individual, it is nobler and more divine to do so for a nation or city-state” (EN I.2.1094b7–10). The two ethical works (the Nicomachean Ethics and the Eudemian Ethics) explain the principles that form the foundations for the Politics: that happiness is the highest human good, that happiness is the activity of moral virtue defined in terms of the mean, and that justice or the common advantage is the political good. Aristotle’s political science thus encompasses the two fields which modern philosophers distinguish as ethics and political philosophy. (See the entry on  Aristotle’s ethics.)  Political philosophy in the narrow sense is roughly speaking the subject of his treatise called the Politics. For a further discussion of this topic, see the following supplementary document: