Aristotle moved to Athens in 367 BC and began to study philosophy. He studied at Plato's Academy. He left Athens twenty years later to study botany and zoology. He became a teacher of Alexander the Great and returned to Athens ten years later to create his own school: the Lyceum. At least twenty-nine of his books have survived, known as the "corpus Aristotelicum." He wrote about logic, physics, optics, metaphysics, ethics, rhetoric, politics, poetry, botany, and zoology.