Plato was the most famous of Socrates' pupils, who after Socrates' death carried on most of his work and eventually founded his own school, the Academy, in 385. We know much about Plato's teachings, because he wrote dialogues between Socrates and others that would explore philosophical issues. These dialogues would be used in his school as starting points for discussion; these discussions and Plato's final word on the dialogues have all been lost to us. However, Plato later began to develop his own philosophy and the Socrates of the later dialogues does more teaching than he does questioning.
Plato's teachings have been among the most influential in the history of Western civilization. If Plato's Republic has a single unifying theme, it is to show that "the life of the just person is intrinsically preferable to any other life." (Partridge, n.d.). In order to prove this, Socrates is made to investigate the concept of justice, and just what this term means, and all relevance related to this. After an elaborate effort which spans over three of the ten books of the Republic, Socrates and his two interlocutors discover just what justice really is. "Justice is shown to be a property of a soul in which its three parts do their proper work and refrain from doing the job of another part." (Partridge, n.d.).
Plato's account initiated the long tradition of reflection that later interacted with the Jewish, Christian, and later Islamic Biblical concepts of creation. These formed the foundation for the conclusion that organic beings were the product of external creative design. One common meaning of 'teleology' as encountered in discussions of evolution of Darwin - that of externally imposed design by an intelligent agency (demiurge, nature, God) - dates from Plato's account. Plato is deeply impressed with the order and beauty he observes in the universe, and his project in the dialogue is to explain that order and beauty. The universe, or so he proposes, is the product of rational, purposive, and beneficent agency. The governing explanatory principle of the account is teleological: the universe as a whole as well as its various parts are so arranged as to produce a vast array of good effects. As Plato tells it, the beautiful orderliness of the universe is not only the manifestation of Intellect, it is also the model for rational souls to understand and emulate.
Plato was always concerned with the fundamental philosophical problem of working out a theory of the art of living and knowing. Plato became convinced of the ultimately harmonious structure of the universe, but he even went further than his mentor - Socrates - in trying to construct a comprehensive philosophical scheme. Plato's primary goal was to show the rational relationship between the soul, the state, and the cosmos. In the Republic, he shows how the operation of justice within the individual can best be understood through the analogy of the operation of justice within the state, which Plato proceeds to set out in his conception of the ideal state. It is a highly