section_path: Legacy/Unwritten doctrines
section_name: Unwritten doctrines
paragraph_text: Unwritten doctrines
  
  Plato's unwritten doctrines are, according to some ancient sources, the most fundamental metaphysical teaching of Plato, which he disclosed only orally, and some say only to his most trusted fellows, and which he may have kept secret from the public, although many modern scholars doubt these claims. A reason for not revealing it to everyone is partially discussed in Phaedrus where Plato criticizes the written transmission of knowledge as faulty, favouring instead the spoken logos: "he who has knowledge of the just and the good and beautiful... will not, when in earnest, write them in ink, sowing them through a pen with words, which cannot defend themselves by argument and cannot teach the truth effectually." It is, however, said that Plato once disclosed this knowledge to the public in his lecture On the Good (Περὶ τἀγαθοῦ), in which the Good (τὸ ἀγαθόν) is identified with the One (the Unity, τὸ ἕν), the fundamental ontological principle.
  
  The first witness who mentions its existence is Aristotle, who in his Physics writes: "It is true, indeed, that the account he gives there of the participant is different from what he says in his so-called unwritten teachings (Ancient Greek: ἄγραφα δόγματα, romanized: agrapha dogmata)." In Metaphysics he writes: "Now since the Forms are the causes of everything else, he supposed that their elements are the elements of all things. Accordingly, the material principle is the Great and Small, and the essence is the One (τὸ ἕν), since the numbers are derived from the Great and Small by participation in the One". "From this account it is clear that he only employed two causes: that of the essence, and the material cause; for the Forms are the cause of the essence in everything else, and the One is the cause of it in the Forms. He also tells us what the material substrate is of which the Forms are predicated in the case of sensible things, and the One in that of the Forms – that it is this the duality (the Dyad, ἡ δυάς), the Great and Small (τὸ μέγα καὶ τὸ μικρόν). Further, he assigned to these two elements respectively the causation of good and of evil".
  
  The most important aspect of this interpretation of Plato's metaphysics is the continuity between his teaching and the Neoplatonic interpretation of Plotinus or Ficino which has been considered erroneous by many but may in fact have been directly influenced by oral transmission of Plato's doctrine. A modern scholar who recognized the importance of the unwritten doctrine of Plato was Heinrich Gomperz who described it in his speech during the 7th International Congress of Philosophy in 1930. All the sources related to the ἄγραφα δόγματα have been collected by Konrad Gaiser and published as Testimonia Platonica.