 In considering practical reason to be the domain of both ethics and politics, Aristotle follows Plato in drawing no sharp line between those two domains (see on this point for ancient testimonies and modern arguments respectively, Bodéüs 1993: 22–24 and 59–63, and Vander Waerdt 1991, though for a contrary argument, see Duvall and Dotson 1998). In fact he closes his Nicomachean Ethics by remarking that for most people, the practice of ethics can only be ensured by their being governed by law, which combines necessity (compulsion) with reason. Because, for most people, the ethical life presupposes government by law, the student of ethics must become a student of political science, studying the science of legislation in light of the collection of constitutions assembled by Aristotle and his school in the Lyceum. All but part of one of the over one hundred items in this collection reported in antiquity have been lost: a considerable part of the analysis of the “Constitution of Athens” was recovered from a papyrus discovered in the nineteenth century. Aristotle’s theoretical claims about the nature of politics in the Politics must be understood against this backdrop. The legislator (whose standpoint is adopted in the Politics, see the entry on  Aristotle’s political theory)  needs to have a grasp of the nature of politics as such (pursued especially in Books I and III); an understanding of the major faultlines in the interpretation and practice of politics (pursued especially in Books II and IV–VI); and a grip on the structure and characteristics of the specific city for which he aims to legislate (pursued also in Book II for existing constitutions and constitutional models; Books IV–VI for types of flawed constitutions; and Books VII–VIII for the “best constitution” (1323a14).