Plato is primarily concerned with knowing the good. In "The Republic", Plato intends to define justice and describes an elaborate city-state setup with the goal of being a just city. A guardian class of philosophers rules in Plato's city, because these are the only people who can know the good. Everyone else's role in the city is to do their work to support the city so that the guardians are able to philosophize. Aristotle does not follow this concept of knowing the good, but instead advocates doing good. …
