Sphaerus

Sphaerus (Greek: Σφαῖρος; c. 285 BC – c. 210 BC) of Borysthenes or the Bosphorus, was a Stoic philosopher.

Life

He studied first under Zeno of Citium, and afterwards under Cleanthes. He taught in Sparta, where he acted as advisor to Cleomenes III. He moved to Alexandria at some point, (possibly when Cleomenes himself was exiled there in 222 BC) where he lived in the court of Ptolemy IV Philopator. Sphaerus had a considerable reputation among the Stoics for the accuracy of his definitions.

Diogenes Laërtius and Athenaeus tell a story of how he once saved himself from admitting that he had been deceived by a trick played upon him by King Ptolemy:

Writings

According to Diogenes Laërtius, Sphaerus wrote the following works: