Posidonius Biography


(Literature and the Ancient World, Critical Edition)
0111205879-Posidonius.jpg Posidonius (Library of Congress) Published by Salem Press, Inc.


Posidonius (pohs-ih-DOH-nee-uhs), a Stoic philosopher, studied under Panaetius of Rhodes before the latter’s death in 104 b.c.e. He then became a citizen of Rhodes. Probably in the 90’s b.c.e., he toured the Mediterranean world to collect material for his studies. Returning to Rhodes, Posidonius was elected to the office of the prytany and was sent on an embassy to Rome in 87/86 b.c.e. Eminent Romans, such as Pompey the Great and Cicero, came to hear him. He died shortly after a second embassy to Rome in 51 b.c.e.

Posidonius’s writings show a wide range of interests. For example, in his analysis of natural phenomena, he was most well known for his explanation of the relation between tides and the Moon. In ethics, his most profound contribution was in the field of psychology and the examination of the emotions. His Histories (now lost) continued Polybius’s work, extending it from 146 to 86 b.c.e. An obsession with etiology, the examination of causes, underlies his exploration of all these subjects.


The writings of Posidonius survive only in citations in later writers’ works. His investigation of natural phenomena and history drew most interest in antiquity. Unfortunately, the fragmentary remains of his work do not adequately indicate his interest in etiology, which links the various parts of his once vast corpus.

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(The entire section is 542 words.)

Posidonius Biography

(Historic Lives: The Ancient World, Prehistory-476)

Article abstract: Greek philosopher{$I[g]Greece;Posidonius} Though virtually none of his writings survives, it is clear that Posidonius was one of the most influential thinkers of the ancient world. He made important contributions in the fields of philosophy, history, astronomy, mathematics, natural history, and geography.

Early Life

Posidonius (pohs-ih-DOH-nih-uhs) was born in Syria around 135 b.c.e. Some ancient writers refer to him as “The Apamean,” from his birthplace in Syria, which, at that time, was part of the Roman Republic. This vast nation had greatly facilitated the international exchange of knowledge. The dominant philosophy that emerged was Stoicism, named for the Stoa Poecile (the “painted porch”) of the building in Athens where the originators of the doctrine taught. The earliest expression of Stoic philosophy comes from Zeno of Citium (c. 335-261) in Cyprus and Cleanthes of Assos (c. 331-c. 232) in Asia Minor; they were of the Early Stoa, the first period of this doctrine, which lasted from 300 b.c.e. to the beginning of the second century b.c.e. The thinkers of the Middle Stoa introduced this philosophy to Roman culture during the second and first centuries b.c.e. Panaetius of Rhodes (185-109) and his prize student, Posidonius, were the most important figures of the Middle Stoa. Though Stoicism was to remain the dominant philosophy until the second century c.e., Posidonius was the last of the Greek Stoic philosophers.

Posidonius left his home country early in his life and traveled to Athens, where he studied philosophy under Panaetius. After his teacher died in 109, Posidonius traveled for several years throughout North Africa and the western Mediterranean region, including Spain, Italy, and Sicily. During these travels he conducted extensive scientific research. He returned to Greece and settled in Rhodes, the largest island in the Dodecanese group, off the southwest coast of Asia Minor. In Rhodes, he was appointed head of the academy that he would later make the center of Stoic philosophy. Posidonius also became involved in local politics and influenced the course of legislation on more than one occasion. In 87 the Rhodians sent him as an envoy to Rome with the charge of appeasing Gaius Marius. The result of this visit was that Posidonius developed an extreme dislike for Marius and later heavily criticized him in his historical writings.

The Stoic philosophy that Posidonius studied at Athens and taught at Rhodes consisted of three domains of concern: logic, physics, and ethics. Stoic logic included the study of grammar but emphasized the formal nature of reasoning, that is, relations between words, not between words and what they stand for. The relations in rational discourse (as studied by logic) were regarded as reflecting the processes of the cosmos (as studied by physics).

The dominant theme of Stoic physical theory was that the universe is an intelligent living being. The physical theory of the Stoics was equivalent to their theology, for the rational totality was equated with God, Zeus, the logos, or the ordering principles of the universe (all these terms being synonymous within their philosophy). In the physical theory of the Stoics, matter is inert or passive and is acted on by God, the rational active cause. All gradations of being in the universe were regarded as having been formed by this action. According to this philosophy, the action of the rational cause on the matter is cyclical. Throughout the aeons, each cycle begins with the pure active cause organizing the four fundamental elements and ends with a universal conflagration in which all created matter is consumed and the totality reverts to its purified state. Stoic ethical doctrines were perhaps the most famous element of their philosophy and were connected to their cosmological conceptions.

The basic precept of the Stoic ethical system was to live according to the order of the universe. The ultimate goal of ethical action was to achieve self-sufficiency, the only guarantee of happiness. Happiness was regarded as possible only through that which was entirely within the individual’s control, and this state was to be achieved through the practice of the virtues. The most important of the virtues were wisdom, courage, justice, and self-control. The Stoics emphasized two ways of acquiring the virtues: the imitation of exemplary lives and the study of ethics and physics.

It was in the context of these broad doctrines that Posidonius developed his conceptions of humankind and the universe. Though only a few fragments of Posidonius’s writings have survived, he is mentioned by more than sixty ancient writers, and it is through their comments that scholars have been able to reconstruct his philosophy. He is mentioned primarily in the works of Cicero, Strabo, Seneca, and Galen.

Posidonius differed from the Stoic tradition in which he was educated in his concern with empirically oriented scientific investigations. He did, however, adhere to the Stoic division of philosophy into the branches of logic (or dialectics), ethics, and physics. His teacher, Panaetius, admired Plato, and it was with the development of Posidonius’s philosophy that the influence of Plato on Stoicism truly began. Posidonius also emphasized his agreement with the doctrines of Pythagoras, and, in general, he argued for the reconciliation of all opposing philosophies.

Life’s Work

While developing his own version of Stoic philosophy at his academy in Rhodes, Posidonius became quite famous. In 78, the famous Roman orator Cicero attended his school. In fact, Cicero requested of Posidonius that he edit his account (in Greek) of the conspiracy of Catiline. Posidonius declined the request.

Posidonius’s most famous visitor was the Roman general Pompey the Great, who visited Posidonius’s school on two different occasions in order to attend lectures: in 72, when Pompey returned from the eastern part of the Empire after action in the Mithradatic War, and again five years later, after a victorious campaign against pirates in the Mediterranean Sea. As a gesture of respect for the great philosopher, Pompey ordered his officers to lower their fasces (bundles of rods with axes in them, which were used as scepters by Roman leaders) at the door of Posidonius’s school. Posidonius greatly admired Pompey and added an appendix to his Histories (now lost), which was devoted exclusively to Pompey’s campaigns in the East.

Posidonius’s history of the world began with the year 146 b.c.e. (the point at which the famous history of Polybius ended) and continued up to the...

(The entire section is 2738 words.)