Claudius Ptolemaeus, better known as Ptolemy, was the most important Hellenistic writer on the mathematical investigation of celestial phenomena. His writings on astronomy and astrology, but also on optics and music, represent the highest achievement of classical science. They were the authoritative works in these disciplines for well over a millennium.
Ptolemy is extremely stingy with autobiographical information, if by that we mean facts and incidents concerning his upbringing, education, and career. As a result, we know hardly anything about his life. On the other hand, he reveals much about his decision to work in mathematics as well as the personal goals he set for himself (see below). We can date the active period of …
Langermann, Y. Tzvi. "Ptolemy". The Literary Encyclopedia. First published 16 May 2009
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