Le Bien selon Numénius et la République de Platon

Among Plato’s dialogues, the Timaeus was the most authoritative for Middle Platonists. But alone it does not suffice to explain some of the most important doctrines defended by these philosophers. A remarkable example is the doctrine of the the three Principles (God, Ideas, matter), which charaterizes imperial Platonism, and which it cannot be stated on the basis of the Timaeus alone. In my paper I show that Numenius was influenced by the Republic as well: in the metaphor of the sun he found the Good as first principle and an indication of a second principle which is further subdivided into a Intellect thinking the ideas and into a demiurge ordering the universe. This interpretation provides him with some interesting solutions. But such an influence also raises difficulties insofar as the causal role of the first principle is concerned.