Ralph Waldo Emerson once wrote “One man’s justice is another’s injustice.” This statement quite adequately describes the relation between definitions of justice presented by Polemarchus and Thrasymachus in Book I of the Republic. Polemarchus initially asserts that justice is “to give to each what is owed” (Republic 331d), a definition he picked up from Simonides. Then, through the unrelenting questioning of Socrates, Polemarchus’ definition evolves into “doing good to friends and harm to enemies” (Republic 332d), but this definition proves insufficient to Socrates also. Eventually, the two agree “that it is never just to harm anyone” (Re