When Philip of Macedon wanted the best Greek teacher known as a tutor for his son Alexander, he sent for Aristotle. We know very little about the life of Aristotle. He had been a pupil of Plato at the Academy for twenty years and had learnt the best of all that great philosopher could teach him. {383} On his return from Macedonia, he founded a school of his own at Athens, the Lyceum, where he spent the rest of his life teaching and studying. He died in 322 B.C., one year after his pupil Alexander. But if little is known of the details of his life, we know something of his character from things that Alexander said about him, and the esteem in which he held him, and something of the kindliness of his nature from his will which has been preserved. He made provision for all who had faithfully served him and gave many of his slaves their freedom. He had been twice married, and his second wife "who behaved so well towards me," was so provided for that she could marry again, and he made arrangements for the marriage of his daughter. In reading of the life of the Athenian man and the Athenian woman, their ways seem to lie far apart and the wife to have had very little share in the interests of her husband. In his will Aristotle gives us a glimpse of the place which the wife sometimes, at least, held. He left directions that the bones of his first wife, the wife of his youth, were to be taken from their resting-place and buried with his, and this was to be done "as she herself charged." The work of Aristotle is amazing, for he not only wrote on every conceivable subject, but wrote as a master. For more than a thousand years after his death, the books he wrote were studied in schools and universities, and formed the foundation of all education. He wrote on astronomy, mathematics, biology, botany and many other subjects, and he has not only been called the _Father of Natural Science_, {384} but his writings remained the standard authority on many scientific subjects for centuries after his death. Aristotle was more practical than Plato, though less inspiring as a writer. As we have already seen, he, too, wrote about an ideal state in his _Politics_.[22] Aristotle believed that the life of a state was like that of an individual; that the aim of both should be noble living, and that peace and justice between states was just as important as between individuals. But he did more than describe an ideal state; he described the education which such a state should give to its youth, the result of which should be not that a man should boast that his state was great and glorious, but that, being the citizen of such a state, in all that he did he should strive to be worthy of her.