Plato's school What was later to be known as Plato's school appears to have been part of Academia. Plato inherited the property at the age of thirty, with informal gatherings which included Theaetetus of Sunium, Archytas of Tarentum, Leodamas of Thasos, and Neoclides. According to Debra Nails, Speusippus "joined the group in about 390 BC". She claims, "It is not until Eudoxus of Cnidos arrives in the mid-380s BC that Eudemus recognizes a formal Academy." There is no historical record of the exact time the school was officially founded, but modern scholars generally agree that the time was the mid-380s, probably sometime after 387 BC, when Plato is thought to have returned from his first visit to Italy and Sicily. Originally, the meetings were held on Plato's property as often as they were at the nearby Academy gymnasium; this remained so throughout the fourth century. Though the academy was open to the public, the main participants were upper-class men. It did not, at least during Plato's time, charge fees for membership. Therefore, there was probably not at that time a "school" in the sense of a clear distinction between teachers and students, or even a formal curriculum. There was, however, a distinction between senior and junior members. Two women are known to have studied with Plato at the Academy, Axiothea of Phlius and Lasthenia of Mantinea. Diogenes Laërtius divided the history of the Academy into three: the Old, the Middle, and the New. At the head of the Old he put Plato, at the head of the Middle Academy, Arcesilaus, and of the New, Lacydes. Sextus Empiricus enumerated five divisions of the followers of Plato. He made Plato founder of the first Academy; Arcesilaus of the second; Carneades of the third; Philo and Charmadas of the fourth; and Antiochus of the fifth. Cicero recognised only two Academies, the Old and New, and had the latter commence with Arcesilaus. Old Academy Plato's immediate successors as "Scholarch" of the Academy were Speusippus (347–339 BC), Xenocrates (339–314 BC), Polemon (314–269 BC), and Crates (c. 269–266 BC). Other notable members of the Academy include Aristotle, Heraclides, Eudoxus, Philip of Opus, and Crantor. In at least Plato's time, the school did not have any particular doctrine to teach; rather, Plato (and probably other associates of his) posed problems to be studied and solved by the others. There is evidence of lectures given, most notably Plato's