Raised in Apamea, Syria, Posidonius, or "of Rhodes," was a Greek Stoic philosopher, politician, astronomer, geographer, historian, and poet. He should have been hailed as His generation's first polymath. His substantial work still survives only in fragments. Historically authors such as Strabo and Seneca provide the most important details about his life. Posidonius, nicknamed the "Athlete," was born in northern Syria to a Greek family at Apamea, a Hellenistic city on the Orontes River. Posidonius finished his higher education at Athens where he was an ancient tutor of the Stoic school, Panaetius. Yet he quickly disagreed with the Stoic teachings and engaged in heated discussions with many other Stoic thinkers of the day. In his book On the Doctrines of Plato and Hippocrates Galen outlines the events leading to Posidonius 'confrontation and final split with the Stoics. Posidonius eventually gave up Stoicism and turned to another philosophical course, Plato but mainly Aristotle, remaining a faithful adherent of the doctrines of Aristotle until his death. At around 95 BCE he settled and became a resident in Rhodes, a maritime state with a reputation for scientific study. Posidonius strongly engaged in the political life of Rhodes and the positions he held clearly indicate his elevated standing. He held the highest public office, as one of the Prytaneis Rhodes. During the Marian and Sullan eras, in 87–86 BCE he served as ambassador to Rome. Posidonius has accepted Rome, along with other Greek writers, as the stabilizing force in a tumultuous world. For him, not only was his friendship with the roman ruling class politically significant and necessary, but also significant to his science work. His entrance into government gave Posidonius strong links, far outside Roman influence, to finance his journeys to far-off places. Having settled in Rhodes, Posidonius made one or more journeys in the Roman world, and even beyond its borders, to perform scientific research. He sailed into north Africa, Greece, Hispania, Italy, Sicily, Dalmatia, Gaul, Liguria, and the Adriatic's eastern coasts. Posidonius could find tides much higher in Hispania, on the Atlantic coast at Gades, than in his native Mediterranean. He wrote that normal tides are related to the orbit of the Moon, while tidal heights differ with the Moon's cycles and he hypothesized on the periodic tidal cycles associated with the equinoxes and solstices. He'd studied the Celts of Gaul. And among them, he left simple accounts of incidents that he experienced with his own eyes: people paying to cause their throats to be slit for public amusement, and the nailing of skulls to doorways as trophies. But he noticed that the Celts revered the Druids, whom Posidonius regarded as philosophers, and argued that even among the barbarians, "pride and ambition give way to knowledge, and Ares is in awe of the Muses." He wrote a geographical treatise on the lands of the Celts that has since been lost but which is frequently alluded to in the works of Diodorus of Sicily, Strabo, Caesar and Tacitus. Posidonius 'extensive writings and lectures earned him reputation as a scholar and made him popular in the Graeco-Roman world, and a school in Rhodes grew up around him. His grandson Jason, who had been his daughter's son and Nysa's Menekrates, followed in his footsteps and started the school of Posidonius at Rhodes. Though little is known about his school organization, it is clear that there was a constant stream of Greek and Romanian pupils in Posidonius. Philosophy was the ultimate master art for Posidonius, and all of the different sciences were secondary to philosophy which could describe the cosmos by itself. Both his plays had been inseparably philosophical, from science through to history. In philosophy, Posidonius proposed a principle of universal "sympathy," the reciprocal interrelationship of all structures in the world from heaven to earth, as part of a spiritual scheme uniting humanity and all bodies in the universe, including those that were temporally and spatially distinct; While his teacher Panaetius opposed divination, Posidonius used platonic philosophy as a kind of scientific principle to maintain his belief in divination, whether by astrology or prophecy visions.