In book II of The Republic of Plato Glaucon says that he will "restore Thrasymachus' argument" (line 358c) that proves injustice is better than justice. He first talks about how justice came about. Then makes a second point that people practice justice without their own will and he ends with his third point that the unjust man's life is better then the just man's life. Glaucon backs up all of his points with examples of injustices and being just.
In the beginning of his speech, Glaucon states that he wants everyone to know about justice and how it came about: "Now listen to what I said I was going to tell first-what justice is and where it came from" (line 358e). He then goes on saying that performing injustices was good and enduring these injustices was bad, and the pain felt was worse then the joy in performing the injustices: "They say that doing injustice is naturally good, and suffering injustice bad, but that the bad in suffering injustice far exceeds the good in doing it" (line 358e). Next, when two people would perform injustices upon one another and see what both sides felt like they sat down and started to form laws against injustice: "When they would do injustice to one another and suffer it and taste of both its seems profitable to set down a compact among themselves neither to do injustice nor to suffer it" (lines 358e-359a). Then, Glaucon states that this is the start of justice which is something bounded by what is most desirable, performing injustice and getting away with no consequences, and what is least desirable, enduring it and having no ability to get revenge: "And this, then, is the genesis and being of justice; it is a mean between what is best-doing injustice without paying the penalty-and what is the worst ...