Sphaerus

Sphaerus (, sometimes transliterated as Sphaeros; – ) of Borysthenes or the Bosphorus, was a Stoic philosopher.

==Life== Sphaerus 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.