Posidonius was a Stoic philosopher, historian, and scientist of the Hellenistic period. He was born around 135 BCE in Apamea, Syria, and died around 51 BCE. He studied in Athens before settling on the island of Rhodes, where he founded an influential school and served as a leading citizen. His school attracted prominent Roman figures, including Cicero.
He was an extraordinarily wide-ranging thinker, but none of his works survive complete. His ideas are known only through fragments and summaries in later writers. His writings formed a vast collection intended to unify all knowledge. They included major works on physics and the cosmos, theology, ethics, and psychology — the Greek of the summaries names the triad inquiry into living things, theology, and ethics. He also wrote a 52-volume history continuing the work of Polybius, and specialized studies on geography, astronomy, and anthropology.
Posidonius is counted among the last great polymaths of the ancient Greek world. He sought to explain everything—from the movements of the stars to human emotions—within a single, rational Stoic system. His scientific observations, such as his estimate of the Earth's circumference and his theories on tides — the tide fragments speak of the tide, the sea's ebb and flow — were influential for centuries. Through his teaching and his Roman connections, he played a key role in transmitting Greek philosophy and science to the Roman world.
Available Works
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