Plato was born c. 427 B.C. in Athens, Greece, to an aristocratic family very much involved in political government. Pericles, famous ruler of Athens during its golden age, was Plato's step-father. Plato was well educated and studied under Socrates, with whom he developed a close friendship. When Socrates was publically executed in 399 B.C., Plato finally distanced himself from a career in Athenian politics, instead becoming one of the greatest philosophers of Western civilization. Plato extended Socrates's inquiries to his students, one of the most famous being Aristotle. Plato's The Republic is an enduring work, discussing justice, the importance of education, and the qualities needed for rulers to succeed. Plato felt governors must be philosophers so they may govern wisely and effectively. Plato founded the Academy, an educational institution dedicated to pursuing philosophic truth. The Academy lasted well into the 6th century A.D., and is the model for all western universities. Its formation is along the lines Plato laid out in The Republic. Many of Plato's essays and writings survive to this day. Plato died in 347 B.C. at the age of 80.
Xenophon's life and personality is better known to us, perhaps, than that of any other Greek who lived before Alexander the Great. Much of his considerable output of historical writing and essays is frankly or implicitly autobiographical. He reveals himself as one of those many Athenians and other Greeks who turned to autocratic political models, including admiration of Persia, after the excesses of the Athenian democracy led to disaster in the Peloponnesian War. He also reveals himself as much more than a literary man and a critic of his times. A gentleman adventurer and something of a professional soldier, he followed in turn the philosopher Socrates, the Persian prince Cyrus the Younger, and the Spartan king Agesilaus, all of whom he wrote about with an air of close personal knowledge. His works include the autobiographical Anabasis, an account of his service with a mercenary Greek army that marched from Mesopotamia to the Black Sea after the defeat and death of the younger Cyrus. It provides the most detailed single perspective on the military practices and military mentality of Xenophon's age. His Hellenica, by contrast, is an impersonal continuation to the end of the Peloponnesian War of the work of Thucydides and a patchy memoir that concentrates on Sparta's fortunes until the definitive end of its power in 362 b.c. Xenophon's other major works are the Cyropaedia and the rambling Socratic dialogues known as the Memorabilia. The Cyropaedia is a fictional idealization of the career of Cyrus the Great, the only great conqueror known to the Greeks before Alexander. Often regarded merely as a novel, it is a species of a priori historical reconstruction. A retrojection of the military science and political values of the day into a largely unknown Persia of the past, it is intended to explain Cyrus's success on rational principles. The Memorabilia and the Socratic Apology that comes down with them contain nothing of philosophical value but are thought by some scholars to offer a possible corrective to Plato's altogether too Platonic Socrates. Xenophon had a conventional and second-rate mind, but he is a valuable resource because of his mediocrity. He enables us to make contact with an ordinary intellect from a world that often seems dominated by geniuses.