Letters 89.10

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.

Seneca, Letters to Lucilius 89.10, translated by Richard Mott Gummere