Far from seeing Neo-Platonism as a far-fetched corruption of Plato’s thought, these thinkers emphasize the continuity between Plato and his traditional interpreters (e.g. Plotinus).

The term “unwritten doctrine” or “unwritten dogma” comes from Aristotle’s Physics

“It is true, indeed, that the account he gives there of the participant is different from what he [Plato] says in his so-called unwritten teaching (agrapha dogmata).” – Aristotle, Physics 209b

This secret teaching conforms to something said by Plato in his Seventh Letter:

“Every serious man in dealing with really serious subjects carefully avoids writing” (344c).

What are the so-called “unwritten doctrines”? Aristotle explains it as amounting to the teaching of the “One and the Dyad.” To this is often added the “third hypostasis” of Plotinus, which is “nous” or “intellect.”

Those that favor this interpretation of Plato often see Platonism as reconcilable to Christianity.

Pertinent dialogues to this debate are: Republic, Timaeus, Parmenides, Philebus, Phaedrus, Phaedo and Epistle 7.

“It is true, indeed, that the account he gives there of the participant is different from what he says in his so-called unwritten teaching.”

- Aristotle, Physics 209b

This secret teaching conforms to something said by Plato in his Seventh Letter:

“Every serious man in dealing with really serious subjects carefully avoids writing” (344c).

So what is this secret “unwritten doctrine” of Plato? I can’t write it down. Come to class and find out…

Here’s how it goes:

1. Bill Clinton, George W. Bush and Barack Obama are each “human”.
2. We infer that there must be a Form called “Human-ness” by which these “humans” participate.
3. Now these three men are alike because they are human. Moreover, these humans are like the Form of “Human-ness.” Consequently, we now have new set of things that are human: Human-ness, Bill Clinton, George W. Bush and Barack Obama.
4. We now need a new Form of Human-ness to account for all these human things, including the original Form of “Human-ness”. Let’s call this new overarching Form “Super-Human-ness.”
5. But now we have an entirely new set of things all alike by way of being human: Super-Human-ness, Human-ness, Bill Clinton, George W. Bush and Barack Obama. It doesn’t stop with this third “Super-Form.” We would have to keep on supplying “Super-Duper Form of Human-ness” and “Even-More-Super-Duper Form of Human-ness: it goes on and on forever. We have an infinite regress, which shows that the theory is absurd.

What does this all mean? The theory of forms assumes that predication is explained by participation and that arguments should not be circular. The Third Man Argument indicates a problem.

Here are some helpful articles on the Third Man Argument:

Cohen, S. M., “The Logic of the Third Man,” Philosophical Review 80 (1971) 448-475.

Geach, P. T., “The Third Man Again,” Philosophical Review 65 (1956) 72-82.

Owen, G.E.L., “The Place of the Timaeus in Plato’s Dialogues,” Classical Quarterly n.s. 3 (1953) 79-95; also in Studies in Plato’s Metaphysics, ed. by R. E. Allen (London: Routledge & Kegan Paul, 1965) 313-338.

Sellars, W., “Vlastos and the Third Man,” Philosophical Review 64 (1955) 405-437.

Strang, C., “Plato and the Third Man,” Proceedings of the Aristotelian Society, Suppl. vol. 37 (1963) 147-164; also in Plato: A Collection of Critical Essays, vol. 1, ed. by G. Vlastos (New York: Anchor, 1971) 184-200, and on reserve in OUGL.

Vlastos, G., “The Third Man Argument in the Parmenides,” Philosophical Review 63 (1954) 319-349; also in Studies in Plato’s Metaphysics, ed. by R. E. Allen (London: Routledge & Kegan Paul, 1965) 231-263.

Many believe that the hand gestures of Plato and Aristotle (in the center of the painting) denote two ways of doing metaphysics. Plato points to the heavens–Aristotle to the earth. If look closely, Plato is holding a book: Timaeus, one of his most celestial and abstract dialogues. Aristotle is holding his Nichomachean Ethics, a rather terrestrial treatise.

Here are the philosophers featured by Raphael in the Scuola di Atene by number:

1: Zeno of Citium 2: Epicurus 3: Federico II of Mantua? 4: Boethius or Anaximander or Empedocles?

5: Averroes 6: Pythagoras 7: Alcibiades or Alexander the Great? 8: Antisthenes or Xenophon? 9: Hypatia 10: Aeschines or Xenophon?

11: Parmenides? 12: Socrates 13: Heraclitus (as Michelangelo) 14: Plato (as Leonardo da Vinci) 15: Aristotle

16: Diogenes of Sinope? 17: Plotinus? 18: Euclid or Archimedes with students 19: Strabo or Zoroaster? 20: Ptolemy? R: Apelles (as Raphael) 21: Protogenes

For the all the ladies, the only woman to make it into the painting was Hypatia who is located at #9.