Letter 89 — On the Parts of Philosophy (§10)

“Certain of the Peripatetic school have added a fourth division, “civil philosophy,” because it calls for a special sphere of activity and is interested in a different subject matter. Some have added a department for which they use the Greek term “economics,” the science of managing one’s own household. Still others have made a distinct heading for the various kinds of life. There is no one of these subdivisions, however, which will not be found under the branch called “moral” philosophy.”