The main objective in Plato's philosophy is a creation of a perfect society. He constructs a foundation for a utopian society in his book "The Republic". The purpose of his thought process was to cleanse his society of the woes he felt plagued it and construct a new one. .
Plato lived during the Peloponnesian War, which consequently lead to the end of the Athenian democracy. He had eyewitness account of his mentor's (Socrates) trial and execution. Bitter and angered by the political corruption that gripped the Athenian democratic government, he disengaged from participating in politics. He strongly felt that neither a moral individual nor a state that is rational could be established in a democratic environment. Plato felt that the common man wasn't intelligent or capable of dealing with concepts that influence the state such as economics, policy of foreign affairs and other relative matters. He viewed political incumbents in Athens government as being elected for matters that were irrelevant to main factors that affected the state. Another danger was that excessive liberty for the people of the democratic society could potentially lead to anarchy. In Plato's perfect society, he forged ahead to eliminate the disease (pluralism of friendship) that plagued the human character and society (Class Notes). Essentially, Plato wanted to establish the perfect form of society, linked by one single entity. .
Aristotle, unlike Plato, was not focused or concerned about the idea of a perfect society, instead he wanted to improve upon the one that he was part of during his existence. Rather than develop a framework for a society that is perfect, he suggested that society should, in it self, strive to utilize the best system it can attain. He felt that utopia was abstract and superficial. It wouldn't allow for realistic problem solving solutions. He felt that Plato's view of a strict overhaul of society in general wasn't necessary.