Panaetius, son of Nicagoras, was born around 185-180 BC, into an old and eminent Rhodian family. He is said to have been a pupil of the linguist Crates of Mallus, who taught in Pergamum, and moved to Athens where he attended the lectures of Critolaus and Carneades, but attached himself principally to the Stoic Diogenes of Babylon and his disciple Antipater of Tarsus. Although it is often thought that he was chosen by the people of Lindos, on Rhodes, to be the priest of Poseidon Hippios, this was actually an honour bestowed upon his grandfather, who was also called Panaetius, son of Nicagoras Probably through Gaius Laelius, who had attended the lectures of Diogenes and then of Panaetius, he was introduced to Scipio Aemilianus and, like Polybius before him, gained his friendship. Both Panaetius and Polybius accompanied him on the Roman embassy that Scipio headed to the principal monarchs and polities of the Hellenistic east in 139-138 BC. Along with Polybius, he became a member of the Scipionic Circle. He returned with Scipio to Rome, where he did much to introduce Stoic doctrines and Greek philosophy. He had a number of distinguished Romans as pupils, amongst them Q. Scaevola the augur and Q. Aelius Tubero the Stoic. After the death of Scipio in spring 129 BC, he resided by turns in Athens and Rome, but chiefly in Athens, where he succeeded Antipater of Tarsus as head of the Stoic school. The right of citizenship was offered him by the Athenians, but he refused it. His chief pupil in philosophy was Posidonius. He died in Athens sometime in 110/09 BC, the approximate year in which L. Crassus the orator found there no longer Panaetius himself, but his disciple Mnesarchus.
Philosophy
With Panaetius began the new eclectic shaping of Stoic theory; so that even among the Neoplatonists he passed for a Platonist. For this reason also he assigned the first place in philosophy to Physics, not to Logic, and appears not to have undertaken any original treatment of the latter. In Physics he gave up the Stoic doctrine of the conflagration of the universe; tried to simplify the division of the faculties of the soul; and doubted the reality of divination. In Ethics he recognised only a two-fold division of virtue, the theoretical and the practical, in contrast to the dianoetic and the ethical of Aristotle. He attempted to bring the ultimate goal of life closer to natural impulses, and to show by similes the inseparability of the virtues. He argued that the recognition of the moral, as something to be striven after for its own sake, was a fundamental idea in the speeches of Demosthenes. He rejected the doctrine of apatheia, and instead affirmed that certain pleasurable sensations could be regarded as in accordance with nature. He also insisted that moral definitions should be laid down in such a way that they might be applied by the person who had not yet attained to wisdom.
Writings
''On Duties''
The principal work of Panaetius was, without doubt, his treatise On Duties composed in three books. In this he proposed to investigate, first, what was moral or immoral; then, what was useful or not useful; and lastly, how the apparent conflict between the moral and the useful was to be decided; for, as a Stoic, he could only regard this conflict as apparent not real. The third investigation he had expressly promised at the end of the third book, but had not carried out; and his disciple Posidonius seems to have only timidly and imperfectly supplied what was needed. Cicero wrote his own workOn Duties in deliberate imitation of Panaetius, and stated that in the third section of the subject that he did not follow Posidonius, but instead that he had completed independently and without assistance what Panaetius had left untouched. To judge from the insignificant character of the deviations, to which Cicero himself calls attention, as for example, the attempt to define moral obligation, the completion of the imperfect division into three parts, the rejection of unnecessary discussions, small supplementary additions, in the first two books Cicero has borrowed the scientific contents of his work from Panaetius, without any essential alterations. Cicero seems to have been induced to follow Panaetius, passing by earlier attempts of the Stoics to investigate the philosophy of morals, not merely by the superiority of his work in other respects, but especially by the effort that prevailed throughout it, laying aside abstract investigations and paradoxical definitions, to demonstrate the philosophy of morals in its application to life. Generally speaking, Panaetius, following Aristotle, Xenocrates, Theophrastus, Dicaearchus, and especially Plato, had softened down the severity of the earlier Stoics, and, without giving up their fundamental definitions, had modified them so as to be capable of being applied to the conduct of life, and clothed them in the garb of eloquence. That Cicero has not reproduced the entire contents of the three books of Panaetius, we see from a fragment, which is not found in Cicero, preserved by Aulus Gellius, and which acquaints us with Panaetius's treatment of his subject in its rhetorical aspects.
Other works
Panaetius also wrote treatises concerning On Cheerfulness; on the Magistrates; On Providence; On Divination; a political treatise used by Cicero in his De Republica; and a letter to Quintus Aelius Tubero. His work On Philosophical Schools appears to have been rich in facts and critical remarks, and the notices which we have about Socrates, and on the books of Plato and others of the Socratic school, given on the authority of Panaetius, were probably taken from that work.
