Lives of the Stoics: The Art of Living From Zeno to Marcus Aurelius

In his writings, Posidonius held that the mind seeks wisdom and what is truly good, whereas the lower parts of the soul seek power and the glory of victory (like Pompey), as well as bodily pleasure. Good habits and lifestyle—set in place by the mind—are checks against these irrational parts of the soul. This idea that part of us is rational and part of us is not was a fairly radical departure for the Stoics, who had long held that the whole self was rational.

But this inner battle—as Martin Luther King Jr. would later call the Civil War between the “North” and “South” of our souls—rings true to any person with a shred of self-awareness. We have competing parts within us, and what matters in life is which side we choose to turn ourselves over to. One must design one’s life, Posidonius said, “to live contemplating the truth and order of the universe and promoting it as much as possible, being led in no respect by the irrational part of the soul.” This was a feat that Marius and Sulla, Athenion and, sadly, even Pompey could not seem to achieve, despite all their cunning or military might.

That’s because it’s really, really hard to do—whether you’re a genius or a conqueror. If you can do it, though, the Stoics believed, you will produce something far more impressive than brilliant writing or splendid victories.

Earlier Stoics had attempted to divide the philosophy into three parts, using the analogy of a farm or an orchard, with a field (physics), fruit (ethics), and fence (logic). Sextus Empiricus tells us that Posidonius differed: “Since the parts of philosophy are inseparable from each other, yet plants are distinct from fruit and walls are separate from plants, he claimed the simile for philosophy should rather be a living being, where physics is blood and flesh, logic the bones and sinews, and ethics the soul.” It’s the perfect metaphor for the Stoics too, because philosophy is meant to be lived as a human being.

Building from Chrysippus and Zeno, Posidonius took this idea even further. He saw the entire cosmos as a sentient, living being in which all things are interconnected (sympatheia). The study of science can sometimes lead a person to atheism, but in Posidonius’s case his experiments with the tides and his observations of the stars had given him a strong sense of a creator—that there was a providential fate governing the universe. Pushing beyond Chrysippus’s “no shoving” rule, he believed every human being was quite literally on the same team. We are all tied together in cosmic sympathy, Posidonius believed, and none of us are entirely self-sufficient or autonomous. Each of us has been given a role in this large body—one of us is a finger, another a skin cell, another a liver—and we exist in collaboration and tension with each other. It was God, he thought, that ran through this organism as pneuma—a kind of soul of the universe.

In his later years Posidonius dedicated himself almost entirely to completing his great histories. Spanning fifty-two volumes and representing a full third of his entire literary output, his histories picked up at Carthage in 146 BC with Scipio Aemilianus and continued up to Sulla’s sack of Athens in 86 BC. Strabo says that he was even writing a separate work dedicated entirely to Pompey. His known works ranged from those on fate and ethics to others dealing with emotions and the ever-present enemy for the Stoics: anger. He also wrote on grief and duty, and of course many scientific books based on his early explorations on the oceans, weather, and circumnavigation of the earth.

Although only fragments of these great works survive and Posidonius is mostly unknown today, he was a towering figure in his own time and for long after. Centuries later, Saint Augustine, in his famous City of God, took the time to call him out by name and respond to the most scientific of the Stoics, if only to criticize his use of astrology. Posidonius may not be a household name today, but what author wouldn’t have been satisfied to still be cited some five hundred years after his death? And by a saint no less?

Posidonius worked and lived in many places in his long life—Syria, Athens, Rome, and Rhodes—and he traveled almost the entirety of the known world. He wrote many books. He advised many powerful men. He was one of the smartest men of the ancient world—a small part of a cosmic universe, by his own admission, but an impressive contributor nonetheless.

And yet even geniuses are eventually forgotten, and ultimately all of them are mortal. No Stoic would dispute or fight this, Posidonius least of all.

In 51 BC, he died peacefully at age eighty-four, and though we don’t have any record of it, we can imagine him having learned to depart from the world a happier and more grateful man than what he had seen of Marius’s haunting and ignoble end.

DIOTIMUS THE VICIOUS (Die-oh-TEEM-us)

Origin: Unknown

B. Unknown

D. Unknown (100 BC?)