Peripatetic school used by earlier philosophers such as Socrates. Aristotle and his colleagues first began to use the Lyceum in this way about 335 BC, after which Aristotle left Plato's Academy and Athens, and then returned to Athens from his travels about a dozen years later. Because of the school's association with the gymnasium, the school also came to be referred to simply as the Lyceum. Some modern scholars argue that the school did not become formally institutionalized until Theophrastus took it over, at which time there was private property associated with the school. Originally at least, the Peripatetic gatherings were probably
Peripatetic school known with varying levels of certainty. A list of names with the approximate dates they headed the school is as follows (all dates BC): There are some uncertainties in this list. It is not certain whether Aristo of Ceos was the head of the school, but since he was a close pupil of Lyco and the most important Peripatetic philosopher in the time when he lived, it is generally assumed that he was. It is not known if Critolaus directly succeeded Aristo, or if there were any leaders between them. Erymneus is known only from a passing reference by Athenaeus.