Lives and Opinions of Eminent Philosophers

...of the school concerned with character, the Ethicists. Dialecticians, on the other hand, are those who occupy themselves with the intricacies original: "τερθρείαν" (terthreian) — refers to the subtle or sometimes trivial hair-splitting involved in logical debate of arguments. There are three parts of philosophy: Physics, Ethics, and Dialectic. Physics is the study of the universe and its contents; Ethics is the study of life and matters concerning us; and Dialectic is that which governs the reasoning of both. Until the time of Archelaus A teacher of Socrates and the last of the major "Physical" philosophers of the Ionian school, the physical branch was the primary form; from the time of Socrates, as previously mentioned, the ethical branch became dominant; and from Zeno of Elea, the dialectical branch began.

Of the Ethical branch, ten schools school: original "αἵρεσις" (hairesis), meaning a "choice" or a system of principles that one chooses to follow have arisen: the Academic, Cyrenaic, Elian, Megarian, Cynic, Eretrian, Dialectical, Peripatetic, Stoic, and Epicurean.

The leaders of these schools were as follows:

• Plato founded the Old Academy.
• Arcesilaus led the Middle Academy.
• Lacydes led the New Academy.
• Aristippus of Cyrene founded the Cyrenaic school.
• Phaedo of Elis founded the Elian school.
• Euclides of Megara founded the Megarian school.
• Antisthenes the Athenian founded the Cynic school.
• Menedemus of Eretria founded the Eretrian school.
• Clitomachus of Carthage founded the Dialectical school.
• Aristotle of Stagira founded the Peripatetic school.
• Zeno of Citium founded the Stoic school.
• The Epicurean school is named after Epicurus himself.

However, Hippobotus in his work On Schools says there are nine schools and systems: first, the Megarian; second, the Eretrian; third, the Cyrenaic; fourth, the Epicurean; fifth, the Annicerean; sixth, the Theodorean; seventh, the Zenonian (which is the same as the Stoic); eighth, the Old Academic; and ninth, the Peripatetic. He does not include the Cynic, Elian, or Dialectical schools. As for the Pyrrhonian The school of extreme skepticism founded by Pyrrho of Elis school, most do not include it because of its lack of clarity. Some say it is a school in certain respects, but in others it is not. It appears to be a school, for we define a "school" as one that follows—or seems to follow—a specific rational principle based on appearances. In this sense, we could rightly call the Skeptical school a "school." But if we understand a school to be...