Plato, the great philosopher of Athens, was born in 427 BC. In early manhood an admirer of Socrates, he later founded the famous school of philosophy in the grove Academus. Much else recorded of his life is uncertain; that he left Athens for a time after Socrates' execution is probable; that later he went to Cyrene, Egypt, and Sicily is possible; that he was wealthy is likely; that he was critical of 'advanced' democracy is obvious. He lived to be 80 years old. Linguistic tests including those of computer science still try to establish the order of his extant philosophical dialogues, written in splendid prose and revealing Socrates' mind fused with Plato's thought.

In "Laches, Charmides," and "Lysis," Socrates and others discuss separate ethical conceptions. "Protagoras, Ion," and "Meno" discuss whether righteousness can be taught. In "Gorgias," Socrates is estranged from his city's thought, and his fate is impending. The "Apology" (not a dialogue), "Crito, Euthyphro," and the unforgettable "Phaedo" relate the trial and death of Socrates and propound the immortality of the soul. In the famous "Symposium" and "Phaedrus," written when Socrates was still alive, we find the origin and meaning of love. "Cratylus" discusses the nature of language. The great masterpiece in ten books, the "Republic," concerns righteousness (and involves education, equality of the sexes, the structure of society, and abolition of slavery). Of the six so-called dialectical dialogues "Euthydemus" deals with philosophy; metaphysical "Parmenides" is about general concepts and absolute being; "Theaetetus" reasons about the theory of knowledge. Of its sequels, "Sophist" deals with not-being; "Politicus"with good and bad statesmanship and governments; "Philebus" with what is good. The "Timaeus" seeks the origin of the visible universe out of abstract geometrical elements. The unfinished "Critias" treats of lost Atlantis. Unfinished also is Plato's last work of the twelve books of "L