Comparing the political theories of any two great philosophers is a complex task. Plato and Aristotle are two such philosophers who had ideas of how to improve existing societies during their individual lifetimes. While both Plato and Aristotle were great thinkers, perhaps it is necessary first to examine the ideas of each before showing how one has laid the groundwork and developed certain themes for the other.
Plato is regarded by many experts as the first writer of political philosophy. He fashioned a distinctive view of human nature, a view that has had a crucial formative influence on all subsequent theories of human nature. Plato pointed out the distinction between a perfect ideal and its imperfect replicas, and gave the name forms to these particular ideals. Plato's philosophy was centered on his famous Theory of Forms, or Theory of Ideas. The theory is based on the observation that there must be some universal quality that all things classed under a single name share in common. For instance, a tulip is beautiful in a very different way from a human, but both the tulip and the human must share something in common if we are to call them both "beautiful". Plato's answer is that they share in common the Form of Beauty, which is itself invisible, unchanging, and eternal. Forms, Plato argues, transcend the empirical world of sensation, and they include both the physical and ethical dimensions. This means that everything we see has a corresponding form, as does every virtue. There is a form of a tree, and of a human being, and of a flower, just as there is a form of temperance, courage, and justice (Nelson, 35). Forms are perfect, ideal universal ideas, existing as transcendental realitie ...