Justice in the Republic

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" (Republic 335d). This definition is fundamental to the idea of a common good, for harming people according to Socrates, only makes them "worse with respect to human virtue" (Republic 335 C). Polemarchus also allows for the possibility of common good through his insistence on helping friends. To Polemarchus nothing is more important than his circle of friends, and through their benefit he benefits, what makes them happy pleases him. Upon the summation of the debate between Polemarchus and Socrates, Thrasymachus enters into the fray. He states that justice "is nothing other than advantage of the stronger" (Republic 338c), and also that the greatest life is that of perfect injustice, to be found in the life of a tyrant. This definition leaves no room for the common good because it creates a life of competition and materialism, where only the strong survive. Group endeavors are not possible according to Thrasymachus's definition for there can be only one person who comes out on top. Although he leaves no room for the common good in his definition, his life seems to allow for some common good. This is based on his profession as an educator, whose job it is to share knowledge with others and on his willingness to remain a contributing part of the discussion going on at the house of Polemarchus To determine which of these