The Function Argument
In his book, The Republic, Plato recorded a debate between Socrates and Glaucon about whether it is an advantage to live a just life or an unjust life. This paper will layout the arguments and views that Socrates and Glaucon have about the human function and justice.
Socrates starts the debate of justice by first explaining the function argument. A function of something is the ability to perform a certain task well. A virtue allows that object to perform its unique task well. For example Socrates discusses that the function of the eyes is to see (352e). A virtue of the eyes is good vision. The conclusion then follows that good vision allows the eyes to see well. Socrates uses this type of argument to show that a just man lives well. The first premise of Socrates’ argument is that living is a function of the soul (353e). He then says his second premise that justice is a virtue of the soul (353e). The conclusion of the argument follows that a just soul lives well (353e). Socrates gave a logically sound argument so if a person accepts the first two premises the conclusion has to be true. Glaucon will have to attack the argument by disagreeing with either the first or second premise of Socrates’ function argument.
Glaucon has a different understanding of the human function than Socrates. Glaucon believes the human function is controlled by appetites. An appetite is something that a person desires. For example lust, thirst and hunger are all appetites. The human function is to satisfy the appetite of the soul. This belief causes Glaucon to argue that justice is not a virtue of the soul and is in fact a vice or harmful to the soul because justice prevents a person from satisfying their appetites.
Glaucon believes that a person who practices justice does so unwillingly because they do not want to suffer the consequences of injustice (358c). For example a person would want to satisfy their appetite for wealth by stealing from a bank, but they...