We talked about three topics:
I granted that the unjust person that Plato describes is a very unattractive figure. Who would want to live like that? But I questioned whether Plato had shown that an unjust person has to be that way. The unjust characters that Thrasymachus and Glaucon described seem more realistic to me.
I mused about a possible explanation for this. Injustice, as Glaucon and Thrasymachus described it, is an indifference to the rules of justice and fairness. But all the characters in the book are willing to accept a slightly different characterization of injustice as involving a kind of motivation or desire. This is the desire to outdo others or to have more.
I agree that the simple desire to have more than others or just to constantly have more, without thought to what having more is for, is pathological. But I denied that the first way of understanding injustice, as involving an indifference to the rules, has to involve this kind of pathology.