Posidonius

Posidonius (pōsēdō`nēəs), c.135–c.51 B.C., Greek Stoic philosopher, b. Apamea, Syria. He settled in Rhodes after extensive travels. Noted for his learning, Posidonius gave new life to Stoicism by fortifying it with contemporary learning. Although his writings have been lost, it is known that they were copious. He made contributions to Stoic physics and ethics—notably the theory that a vital force emanating from the sun permeated the world and his doctrine of cosmic sympathy, through which man and all things in the universe are united. Other writings dealt with the natural sciences, mathematics, and military tactics. He had strong influence on the Romans.

---

Posidonius 

Born circa 135 B.C., in Apameia, Syria; died 51 B.C., in Rome. Ancient Greek Stoic philosopher. Major representative of the Middle Stoa.

The leader of a school in Rhodes (Rodhos), Posidonius combined the ideas of Stoicism with those of Platonism. He equalled Aristotle in the encyclopedic range of his knowledge. Posidonius wrote works on all aspects of philosophy, as well as on religion, ethics, cosmology, geography, astronomy, mathematics, history, and rhetoric. Only a few fragments of his works have been preserved.

Posidonius refined the Stoic doctrine of the creative fire and its permutations, using the Platonic concept of the Intellect (nous), which he presented not only as the world of ideas and numbers but also as a fiery pneuma that scatters throughout the world the logoi spermatikoi (“seminal reasons”)—the individual, fiery conceptual embryos of all things. Thus, the divine being is a thinking, fiery breath. Posidonius’ doctrine of pneumatic outflows was very important in laying the foundation for the Neo-platonic theory of emanation. Similarly, Posidonius combined the Stoic idea of the cosmos as the circulation of fiery substance with the Platonic doctrine of the harmony of the spheres and the purposeful musical, geometrical, and numerical structure of the cosmos. He also accepted the doctrine of the transmigration and reincarnation of souls, linking the cycle of the births of souls with the periodic burning of the universe (world conflagrations).

The Stoic idea of an all-penetrating world fire and, associated with it, a universal cosmic “sympathy” (the presence of all in everything) led Posidonius to the doctrine of a universal law of nature and fate, which can be understood with the aid of mantics (soothsaying) and astrology. Even though fate is omnipotent, the sage can rise above it by means of knowledge and virtue.

In his philosophy of history Posidonius attempted to combine the teaching of Hesiod about the golden age of man and his gradual rebirth with the concept of culture developed by Democritus, Epicurus, and Lucretius, who asserted that the price of the development of crafts, sciences, and arts is a moral fall that calls for the intervention of laws and philosophers.

WORKS

Posidonius [Works], vol. 1—. The Fragment. Edited by L. Edelstein and J. G. Kidd. Cambridge, 1972.

REFERENCES

Losev, A. F. “Posidonii.” In Istoriia grecheskoi literatury, vol. 3. Moscow, 1960.
Reinhardt, K. Poseidonios. Munich, 1921.
Heinemann, I. Poseidonios’ metaphysiche Schriften, 2nd ed., vols. 1–2. Hildesheim, 1968.

A. F. LOSEV