Plato's Republic Book 1: Against Thrasymachus--is justice merely the advantage of the stronger?

In this video, I begin a series of talks on Plato's Republic, one of Plato's most memorable works. In this first lecture, I consider Plato's response to Thrasymachus in Book I. Thrasymachus contends that justice is nothing but the advantage of the stronger: It is merely the system of morality imposed by rulers over the ruled. Plato, through the character of Socrates, argues against this position, showing that it is undermined by the nature and structure of craft (techne). I then consider how the contemporary Thrasymachean might respond in the voice of Marxism, feminism, or one of the many cottage industries of critical theories, and I offer a pair of responses to such challenges. The first simply notes that the modern Thrasymacheans have only, at best, pointed to the current state of affairs. They have not shown that Plato's contention was contradictory and hence impossible. As a result, the contest between Platonism and Thrasymacheanism becomes a matter of vision and will. The second points to Plato's argument that the perfectly unjust society would be self-undermining. The Thrasymachean vision of the world is ultimately impossible.

You can find a corresponding essay on my blog here: http://premieretat.com/against-thrasymachus-republic-book-i/

The picture used in the thumbnail of this video is Giotto's The Casting Out of the Moneychangers and is in the public domain. It can be found here: https://commons.wikimedia.org/wiki/File:Giotto_-_Scrovegni_-_-27-_-_Expulsion_of_the_Money-changers_from_the_Temple.jpg