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

It can be easy, in retrospect, to see “the Stoics” as a unified voice. To view the early days of philosophy with Zeno and Cleanthes and their first students as salad days of teamwork and friendship. It was, after all, a school, with a straightforward claim: that virtue was the path to happiness and from virtue came a better flow of life.

We must live in harmony with nature, the Stoics had taught since the beginning, so where could the conflict possibly be?

The answer, of course, is everywhere. For instance, what exactly do “nature” and “virtue” entail? Whose definition is correct? Whose prescriptions are best? And who is the true heir to Zeno’s legacy both as the founder of the Stoic school and as the promoter of virtue above all else?

History gives a clear answer—Cleanthes and then Chrysippus (whom you will meet in the next chapter)—though it was never so clean. Written history obscures the also-rans and the contrarians who did not carry the day. There is no such thing as a movement without disagreement, after all, and nothing that involves people does not also involve differing opinions. Stoicism is no exception.

There should be little surprise that knives flashed among the ancient philosophers, as they have and always will flash in academia. A school that venerates reason and grit, courage, and a keen sense of right and wrong above all things is naturally going to attract strong-minded students who don’t like to concede or compromise. The rising popularity of the school only raised the stakes of this conflict.

No one embodied that more than Aristo, the contentious rival son who could have very nearly changed the entire course of Stoic philosophy.

While Cleanthes was Zeno’s favored student and chosen successor in 262 BC, Aristo was an equally promising philosopher, who was far less passive and far less reserved than the hardworking water-carrier who would inherit Zeno’s mantle. Aristo the Bald, of Chios, son of Miltiades, was nicknamed “the Siren” for the persuasive power of his eloquence that wooed audiences, and allegedly led them astray.

A better name would have been Aristo the Challenger, because he was constantly questioning, undermining, and disputing much of the early Stoic doctrine, including their practical rules for daily living.

Some three centuries after the debate with Aristo last ran hot, Seneca would rehearse in great detail the disagreement between Aristo and Cleanthes in a letter to his friend Lucilius, almost in the way a historian might lay out the differences between the American Founding Fathers on the separation of powers.

The dispute? It was over the role of precepts, or practical rules, to guide us in everyday decision making. Rules about how to act in a marriage or how to raise children or how masters ought to treat their slaves. Rules like what to do when your brother makes you angry, or how to respond to the insults of a friend, and what to do when an enemy is spreading lies about you.

These might seem like relatively harmless (and actually helpful) hints, but to Aristo they were crutches that sent people down the path to memorizing a script for the challenges of life. “Advice from old women,” he called it. Aristo argued that the expertise of a javelin thrower in the Olympic Games comes from training and practice, not from studying the target or memorizing rules. You get better by practicing with your javelin. “One who has trained himself for life as a whole,” he said, “does not need to be advised on specifics. He has been taught comprehensively, not how to live with his wife or his son but how to live well, and that includes how to live with members of his family.”

An athlete isn’t thinking on the court or the field; their movements come from the muscle memory of their training, guided by their intuition. It’s from this flow state, rather than from conscious deliberation, that excellence—moral or physical—emerges.

So what Aristo wanted people to focus on were big, clear principles, things that could be internalized by the wise from their training. He wanted the Ten Commandments, not books about what order the sacraments go in. He wanted to give students a North Star to look to—virtue—and believed every caveat and explanation beyond that would lead to confusion.

Virtue was the sole good, Aristo was saying. Everything else was not worth caring about.

This put him at odds with Zeno, who believed there was plenty of gray area in between virtue and vice. Zeno had held that certain things in life, like wealth and health, which have no moral value per se, do tend to approximate the nature of truly good things. Having lots of money isn’t virtuous, but certainly there are virtuous rich people—and like all other fates, financial success presents its own opportunities for moving toward virtue as well as temptations for turning to vice. Zeno’s somewhat ingenious argument was to call these things—being healthy, being handsome, possessing an illustrious last name—“preferred indifferents.” It’s not morally better to be rich than poor, tall than short, but probably nicer to be the former than the latter.

Right?

To Zeno, it was not controversial to say that one could lean toward virtue and still desire wealth or fame or preeminence, for those were tools to employ in the building of an even more virtuous life. In this way, the early Stoics argued that we can and should pursue preferred indifferents as part of the good, virtuous life. It’s a classic middle ground, practical realism to be expected from someone like Zeno who was a merchant before he was a philosopher, as well as precisely the kind of thing that his student Aristo could not stand.

Aristo strongly argued that the goal of life is to live in a state of indifference to everything that is in between virtue and vice, making absolutely no distinction between those tricky things that can be nice to have but dangerous in excess. He didn’t want some complicated list of categories. He didn’t want to rank things in order of their goodness or badness. He didn’t want to consider gray areas or consult a rulebook. He wanted black and white. He wanted to rely on his training and his intuition to immediately know what to do in a given situation.

It’s like the story of a general who, in taking over an important command, was given a thick book of the practices established by the generals who had preceded him. “Burn them,” the general said. “Anytime a problem comes up, I’ll make the decision at once—immediately.”

It certainly sounds impressive: I make no equivocation. There is only good and evil. There can be no in between. A wise man simply knows!

It’s also a pretty ridiculous belief for someone as smart as Aristo, as Cicero would point out. With the refusal to rank or prefer, “the whole of life would be thrown into chaos.” Surely some things are better than others, surely there are general rules that can guide us as we live. We need precedents, because situations are complicated and fast-moving. Because sometimes the people who preceded us were actually wiser, and figured things out by painful experience.

Still, Aristo knew how to argue brilliantly. Disputing Zeno’s notion that health was one of these preferred indifferents, he said that “if a healthy man had to serve a tyrant and be destroyed for this reason, while the sick had to be released from the service and, therewith, from destruction, the wise man would rather choose sickness.” It’s an argument that could be applied to so many of the preferred indifferents. Is it really better to be rich if your wealth makes you the target of those same tyrants? Aren’t there situations where height has disadvantages?

We can easily imagine young students nodding their heads at these disruptive critiques and Zeno struggling to explain himself, despite his relatively commonsense position. (Is it really up for discussion that it’s generally preferable not to be sick?) These questions are also seductively fun to discuss—for in disputing Zeno’s gray area, Aristo was introducing endless amounts of gray himself. He was saying that circumstances always and uniquely alter the value of things.

Aristo’s point in pressing on all these soft spots in the philosophy is that, like the general dispensing with precedents, a skilled pilot doesn’t go to a ship’s manual when he’s hit by a wave—no, he uses his deep grounding in the principles of seamanship and his training and experience to make the right call. There is a part of this argument that appeals to the ego: We want to see ourselves as wise, with flawless intuition. We want to believe that all an athlete is doing is going with the flow. But the best athletes also stick to a strict game plan, they submit to a coach. What tattoos the walls of most locker rooms? Inspirational sayings, reminders, and codes of conduct. There are rules that each athlete is following, that they have to be aware of for their performance to count. It’s less sexy to count those other factors, but it’s the truth. It’s this role—the coach—that Zeno and Cleanthes had attempted to stake out for the philosophy teacher.

Sources tell us that Aristo added to this contrarian approach a rather forceful style, and that he spoke much more than he listened, flouting quite deliberately Zeno’s dictum about the natural ratio between ears and mouths. Diogenes reports that Aristo would discourse at great length, and with little grace, overwhelming weaker minds in the process. At times, Zeno had no choice but to interrupt and cut him off. You’re a babbler, he once shouted at him, and I suspect your father was drunk when he sired you.

It wasn’t a Stoic response, but one every frustrated and exhausted teacher can sympathize with. Still, has yelling ever deterred a contrarian? It didn’t stop Aristo’s questioning or contradictions either. Indeed, his antipathy to Stoic orthodoxy extended into writing, where he attacked his fellow Stoics aggressively, even publishing an argumentative book on Zeno’s doctrines and a book titled Against Cleanthes.

These written attacks were answered, Cicero tells us, by Chrysippus, who returned fire with a book against Aristo, and also had a direct personal confrontation with him about the dangers of his commitment to total indifference. “We might ask,” Chrysippus pressed, “how could we live a life if it didn’t matter to us whether we were well or sick, at ease or racked with pain, whether we could keep off cold or hunger or not.”

Indeed, how could we? Life would be chaos.

Aristo was undeterred, answering with confidence and a smile, “You’ll live, splendidly, wonderfully. You will act as seems right to you, you will never sorrow, never desire, never fear.”

It’s as tempting—and empty—a call as any Siren has ever made. And a little beyond the reach of most, however enticing it sounded. Yes, the true sage firmly grounded in the right principles will intuitively know just what to do in every situation and won’t need a rulebook. But what about the rest of us?

Is that even possible—a world where everyone, as Aristo claimed, should simply do “whatever may enter one’s head”? Is that a world anyone would want to live in?

We can imagine these great Stoics pulling their hair out in frustration. We can see their desperation in their tricks and lost tempers. This guy is giving Stoicism a bad name. I thought we were on the same team here. Aristo presents to us the conundrum that John the Baptist presents to Christians and that contrarian figures have always presented to incipient movements. Is this person a rival or a follower? A saint or a heretic? A friend or a foe? Aristo was all these things, then and now.

Shunned by the Stoics, while perhaps still considering himself in their camp, sharing many of the ideas of the Cynics, influenced by the skeptical Academy, locking horns with the Peripatetics, Aristo by his independence earned himself a spot outside the walls of Athens, away from the Stoa Poikilē, in a Cynic gymnasium called, appropriately, the Cynosarges. As with the Sirens for whom he was nicknamed, men flocked to him. Aristo taught there with other radicals like Antisthenes, one of the founders of the Cynics. Aristo earned fame and was soon regarded as the founder of his own school, as Diogenes tells us: the Aristonians, who were known for persuasiveness and decency.

But as a challenger he had his enemies. He would say that “when people build up their reputations little by little, other people attack from all sides,” which is true, though one suspects his contrarianism and challenging demeanor had something to do with the antagonisms he faced more than anything else. Could a more conciliatory and respectful Aristo have accomplished more? Almost certainly, and it would be left to the later Stoics to prove that working within the system was a more effective way of changing minds than challenging everyone and everything.

Aristo taught that beyond following virtue or excellence, when dealing with indifferents, the wise man will simply do whatever pops into his head. He was the first Stoic we know to push the argument that the wise person is like an actor who willingly takes on the roles assigned by fate. We’ll hear this very same argument from Epictetus centuries later, who himself would reprimand his students for asking for rulebooks, as if they could run their whole life by a script. Aristo and Epictetus both felt that when it came to playing our role in life, the script was already written and we shouldn’t be trying to come up with our own. We should work hard at living up to our given roles. But unlike Aristo, that didn’t stop Epictetus from giving lots of good advice.

Diogenes also tells us that Aristo was fond of the idea that he, being a wise man and having true knowledge, would therefore not be misled by mere opinions. This so alarmed the Stoics that they sent Zeno’s scribe to prove him wrong. The prank was simple: He had one twin deposit a sum with Aristo for safekeeping and then the other brother, pretending to be the one who had deposited the money, come and reclaim it. Aristo, who had so arrogantly claimed that he could make a wise decision in any circumstance, stupidly gave the money to the wrong brother.

It was a simple case where a rule—like checking for identification—was vastly superior than relying on your gut. When Aristo discovered that he had given the money to the wrong brother, he was dumbfounded and embarrassed that his wisdom had been so refuted.

Once again, was it Stoic for them to play such a trick? To do so with the intention of humiliating a fellow Stoic over such a minor difference of opinion? The rift was bigger than that, however.

Aristo’s school, in a kind of deliberate hard fork that deviated from Zeno and Cleanthes, had abolished the topics of physics and logic. The former is beyond us and the latter not worthy of concern, was Aristo’s position. Only ethics mattered, only virtue.

With little irony, this master of clever arguments held that the arguments of a logician were like a spider’s web—clearly a product of expertise, but completely useless (though quite useful to spiders!).

Aristo’s questions encouraged other heterodox and renegade thinkers, which must have created the sense inside third-century BC Athens that Stoicism was a school tearing itself apart.

It should humble and shame us a little to see, in retrospect, how insignificant these intensely—and violently—argued debates were. To the early Stoics who fought them, however, the distinctions of “preferred indifferents” were a matter of life and death. Power and influence and ego played a part in this. Only Cleanthes had kept his day job, which meant that these philosophical debates were everything to a Zeno or a Chrysippus or an Aristo. They were like cloistered monks arguing over how many angels could fit on the head of a pin.

It was the narcissism of wanting to be right—to be the one who settled the debate. With the future of the school up for grabs after Zeno and Cleanthes, who could afford to concede? Being remembered by history does very little for you after you’re dead . . . but it’s hard to be indifferent about your legacy.

All understandable, but hardly philosophical, let alone Stoic. It would have been far more impressive if these men could have prevented antagonisms from dominating their relationships with people with whom they mostly agreed. They should have focused on their work, their self-improvement.

As should we.

In any case, the passing of history sorted it all out. Aristo’s work, and his questions, though quickly stamped out by the Stoics who came after him, would make a great impression on the young Marcus Aurelius. At age twenty-five, a generation or two after Seneca, Marcus found himself reading Aristo and was so shaken by the challenge of Aristo’s questions that he couldn’t sleep and had to step away from them. Instead of seeing a heretic, all he saw was someone urging him not to memorize but to practice and train until virtue became second nature. As he wrote to his rhetoric teacher, Fronto:

Just now Aristo’s writings are delighting and tormenting me at the same time. When they teach virtue, of course they delight me; but when they show how far my own character falls short of those models of virtue, your pupil blushes sadly often, and is angry with himself because, at twenty-five, he has absorbed in his heart nothing as yet of good opinion and pure reason. And so I pay the penalty, I am angry and sad, I envy other men, I fast. The prisoner at present of these cares, every day I put off the task of writing till the next.

In short, forget the precepts. Don’t pore over rules. Just do it.

Marcus knew the history of his school quite well. And he knew that all dogmatic disputes come to naught in the end. It all disappears. It becomes dust or legend, or less than that. Quotations of quotations from books that were lost to time.

All that remains, Aristo would have said, is how we lived our lives, how close we came to virtue in the moments that mattered.