The Answer to Glaucon

Book 9 gives three arguments for the conclusion that the just life is better than the unjust one. They represent Plato’s final answer to Glaucon.

We spent a lot of time on the first two and rushed through the third at the end.

But first, a look at Plato’s theory as a whole

Before jumping into Book 9, I described what I called Plato’s big idea: the city is best off when it is ruled by people who are the best at ruling. This follows from his account of why the just city is good. It is good because everyone in it is doing what they are best at. That includes the guardians: they are the best at ruling.

This is not a democratic conception of the state, but it makes a fair amount of sense. Why strive to have anyone other than those who are best at ruling in charge?

We discussed a variety of ideas about democracy and its alternatives.

For instance, you might say that democracy actually does select the best leaders or, at least, that it does a better job than any known alternative. I think China would be an interesting comparative case here. As Alex pointed out, the Chinese system has a way of selecting political leaders according to merit. It is different than Plato’s system for selecting guardians, of course, but the two systems are similar in that they both seek to train and select the best for political office.

Or you might say, with Kamyab and Karl Popper, that democracy does a better job than the alternatives of getting rid of bad leaders peacefully.

Or, as Will suggested, you might say that individuals have rights to participate in government and that democracy is the best way of respect their rights. If so, it is less important that democracy selects the best. People can use their rights as they please, even if they do a bad job of it.

And, finally, we should take Audrey’s point to heart: aristocracies do not, in fact, serve the interests of the lower classes even if they could do so, in theory. It would be interesting to compare similar countries with different political systems like, say, India and China, to see which system does a better job in advancing the interests of all of its citizens.

Anyway, on with Plato’s answers to Glaucon!

First, tyrants are fearful addicts

Plato’s first argument is that the tyrant, a.k.a. the completely unjust man, is an addict. They tyrant does all sorts of self-defeating things because he is controlled by his appetites. Consequently, he is unhappy, lacks control over his behavior, and lives in fear of others.

The argument is not based on generalizations about actual tyrants. (Would it be true if it were?) In making it, Plato reverts to the analogy between the city and the soul. Slave owners in the city have to fear their slaves and so the tyrant would live in fear of his appetites (see 579). That is not the most persuasive use of the analogy, in my opinion.

Our most important question about the argument took us back to our old friends Thrasymachus and Glaucon (see the handout). It looks to me as though Plato’s characterization of the tyrant is aimed at the character Thrasymachus described as the completely unjust man. Josh and Rosie expressed doubt that he is doing much to explain why Glaucon’s stealthier unjust life is so bad. The unjust person Glaucon described does not seem like the raving maniac described in book 9.

Second, the philosophers’ experience

Plato’s second argument is that the philosophers have experienced the pleasures of each kind of life and know that the life of knowledge and justice is superior to the alternatives.

We practiced putting this into a numbered argument and especially looking for the unstated premise that is needed to make the argument work: the premise that someone who has experience of two kinds of pleasure is a better judge of which one is better than someone who has not had that experience.

Will S. pointed out that there was yet another unstated assumption, namely, that it is possible to compare pleasures as being better or worse. (Although as Will P. noted later in the day, Plato is really comparing lives. I wonder if Will S’s point would still hold, though.)

Kamyab and Bry doubted that the philosophers really do experience other kinds of lives. The do not live as productive people, after all.

Third, the nature of pleasure

Plato’s third argument is the most difficult to assess. He starts with the assumption that pleasure involves filling a kind of void. Then he maintains that the kinds of things the philosophers take pleasure in are more real than the kinds of things others take pleasure in. (Numbers, for instance, are unchanging and perfect while the stuff of the earth is neither.) Assuming that what is more real is more filling than what is less real, Plato concluded that the philosopher’s pleasures are superior to the pleasures that the other kinds of people pursue.

We did not have much time to go into this. I ran through Plato’s ideas about the forms and what the analogy of the cave is supposed to mean. The forms are supposed to be perfect, unchanging, and more fundamentally real than the things we see and experience. But Plato himself is quite open about the fact that he is incapable of saying much about what the forms may be like. His discussion lists his aspirations more than what he can prove or even adequately describe.

Key points

  1. Plato’s undemocratic conception of the state.
  2. The argument that the most unjust man is an unhappy addict.
  3. The argument that the philosophers have experience of all kinds of pleasure and so know which ones are best.


Plato. 1992. Republic. Translated by G.M.A. Grube and C.D.C. Reeve. Indianapolis: Hackett.


There was a handout for this class: 05.PlatoAnswerGlaucon.handout.pdf