Editor’s Note: I first listened to Robertson’s book, How to Think Like a Roman Emperor: The Stoic Philosophy of Marcus Aurelius last year on Audible, bought a hard copy, and I continually recommend it to friends in the military. The below post first appeared on his website and is reprinted with his permission. -Joe
By Donald J. Robertson, author of How to Think Like a Roman Emperor: The Stoic Philosophy of Marcus Aurelius
When I first became involved with teaching Stoicism, I noticed that the audience at talks and conferences was quite a mixed bunch. At first there were mainly classicists and academic philosophers and then psychotherapists like myself, and some research psychologists, became interested in Stoic philosophy. Then I began to notice quite a few life coaches and people involved in corporate training, some sports coaches, and also a number of men and women who were serving in the military.
Each of these groups approaches Stoicism from a different perspective. However, the wonderful thing is that they will all happily sit around and discuss philosophy because they have enough common ground, a shared interest in Stoic literature and ideas. There are also some prominent figures in the modern Stoic community who approach the philosophy from a military perspective.
Lieutenant Colonel Thomas Jarrett spoke recently at the Stoicon Modern Stoicism conference in Athens about the Warrior Resilience Training Program he developed, based on Stoicism, and taught to US troops during the Iraq War. Nancy Sherman, who is currently Distinguished Professor of Philosophy at Georgetown University held the Distinguished Chair in Ethics at the United States Naval Academy, from 1997 to 1999. She’s the author of Stoic Warriors: The Ancient Philosophy Behind the Military Mind (2007).
Former US Secretary of Defence, General James Mattis has stated that he is a fan of Stoicism. While in office, Mattis explained to an audience of military cadets that the Roman emperor Marcus Aurelius, though a philosopher, spent much of his reign far from home, fighting the northern tribes along the Danube. Mattis told them that he thinks the one book every American should read is The Meditations of Marcus Aurelius. “In combat”, he said, “the reason I kept a tattered copy in my rucksack to pull out at times was it allowed me to look at things with a little distance.”
However, the most obvious of a Stoic in the modern military is arguably Vice Admiral James Stockdale, author of Thoughts of a Philosophical Fighter Pilot (1995). Stockdale’s plane was shot down forcing him to eject over North Vietnam at the start of the Vietnam War. He was captured, beaten, and taken to the prison camp known as the Hanoi Hilton, where he was repeatedly tortured over the space of seven years, four of which were spent in solitary confinement. Stockdale had read the Stoic Epictetus years earlier and during his imprisonment he found Stoic philosophy invaluable as a way of coping with the extreme situation he faced. When the war ended, he was released and would lecture on Stoic philosophy and its value to the military.
From Socrates to the Stoics
Despite this interest in Stoicism among the modern military, the personnel I meet are often surprised to learn that some of their favourite philosophers also served in, or commanded, ancient armies. It’s an interesting aspect of the history of philosophy that’s often overlooked.
I thought it was about time that I put brought of these stories together in an article. We’ll begin by discussing Socrates’ military career, and that of his immediate circle, because he was the most important precursor of the Stoic school. His followers, the “Socratics”, especially Antisthenes and Xenophon, provide an important link between his original philosophy and the Stoic school. We’ll then look at the original Stoics, the early Greek school, which was linked to the intellectual circle at the court of King Antigonus II Gonatas of Macedonia, the most powerful military ruler of the period.
Then come a number of famous Stoics during the time of the Roman Republic, from the general Scipio Africanus the Younger, who conquered Carthage, to Cato of Utica, who led the shattered remnants of the Republican army in their doomed last stand against Julius Caesar in the Civil War. Finally, we can look at the Roman Imperial period from the first Roman emperor, Augustus, who studied Stoicism, down to the last famous Stoic of the ancient world, the emperor Marcus Aurelius.
Socrates (Classical Athens)
Most people think of Socrates (470–399 BC) as a bearded but balding, pot bellied, old philosopher. People are often surprised to learn that Socrates was, in fact, also a decorated military hero, renowned among other army veterans for his courage on the battlefield, and for his extraordinary endurance and self-discipline. He served as an Athenian hoplite, or armored infantryman, and distinguished himself in several important battles during the Peloponnesian war (431–404 BC), in which Athens and its allies fought the Peloponnesian League led by Sparta.
References to Socrates’ military service are scattered through a number of ancient texts, from which we learn that he took part in at least three major battles. In Plato’s Apology, Socrates himself cites his service as a hoplite in the Athenian army during the extended siege of Potidaea (432 BC), the Athenian assault on Delium (424 BC) and the expedition to defend the Athenian colony of Amphipolis (422 BC). Socrates was an older soldier, aged between 38 and 48, when these particular battles took place.
[Socrates] was the first to go out as a soldier, when it was necessary, and in war he exposed himself to danger most unsparingly. — Epictetus, Discourses, 4.1
In Plato’s Laches, the eponymous general is portrayed as describing an eyewitness account of Socrates’ exceptional service in the Battle of Delium. In Plato’s Symposium, Alcibiades likewise describes witnessing Socrates’ courage in the battles of Potidaea and Delium. We have a brief mention of Socrates’ service from Xenophon but also a longer portrayal of Socrates discussing military training and tactics, in a manner indicative of his past experience. It’s clear from the surviving writings that Socrates was famous among Athenians for his military endurance, self-discipline, and courage on the battlefield. He is also portrayed as an experienced veteran, whose opinions on military matters are valued by his younger followers.
During the Battle of Potidaea, Socrates single-handedly rescued his friend, the young noble Alcibiades, who had been wounded and disarmed by the enemy. Socrates was awarded the “prize of pre-eminent valour”, which he declined in preference that it should belong to Alcibiades. Plutarch says this award consisted of armor and a crown — it would perhaps be the Athenian equivalent of a . (According to some accounts, though, Socrates was overlooked by the generals in favour of Alcibiades.) Alcibiades was later (c. 416 BC) elected to the rank of Athenian general.
Eight years later, Delium was the first full-scale hoplite battle of the Peloponnesian War, and one of the bloodiest. The Athenians, had attempted unsuccessfully to establish stronghold within enemy territory. Thrown into disarray by the sudden attack of a superior force of Thebans, they made their retreat while being harried by the enemy. The Athenian general Laches had been unhorsed and we’re told Socrates walked by his side, protecting him, so confidently, that none of the enemy dared attack. Plato describes Alcibiades’ account of the story:
I had an even finer opportunity to observe Socrates there [at Delium] than I had had at Potidaea, for I was less in fear because I was on horseback. First of all, how much more sensible he was than Laches; and secondly, it was my opinion… that walking there just as he does here in Athens, ‘stalking like a pelican, his eyes darting from side to side,’ quietly on the lookout for friends and foes, he made it plain to everyone even at a great distance that if one touches this real man, he will defend himself vigorously. Consequently, he went away safely, both he and his comrade; for when you behave in war as he did, then they just about do not even touch you; instead they pursue those who turn in headlong flight. — Symposium
Socrates was a military veteran, approximately 48 years old, with a well-known reputation for his exceptional endurance and courage when the Battle of Amphipolis took place. Diogenes Laertius sounds impressed that he was hardy enough to take to the field once again as a hoplite, despite his age.
He took care to exercise his body and kept in good condition. At all events he served on the expedition to Amphipolis. — Lives and Opinions
Again, the Athenians were defeated. However, we know nothing about Socrates’ role in the battle.
Antisthenes and Xenophon
Socrates’ most famous student was Plato, but he was also one of the younger members of his circle. Plato’s school, the Academy, flourished for centuries. However, there were reputedly ten different Socratic schools that appeared in Greece after Socrates’ death. A small group followed one of Socrates’ oldest and most austere students, Antisthenes, who had fought bravely in the Battle of Tanagra (426 BC), during the Peloponnesian War. We don’t know if he and Socrates ever served together, although it’s possible. Antisthenes is usually credited either with founding the Cynic school or at least inspiring Diogenes of Sinope and his followers and in that regard he can be seen as a precursor of the Stoics. Antisthenes lived in poverty and was looked down on by Athenians because his mother was a foreigner, a “barbarian”, from Thrace.
However, another one of Socrates’ favourite students, a young noble called Xenophon, whose writings survive today, makes it clear that Socrates held Antisthenes in particularly high regard. Xenophon himself later rose to the rank of general and as well as being the author of several Socratic dialogues, including the Memorabilia of Socrates, he is also well-known today as the author of the Anabasis, which tells the story of his military exploits in Persia. Xenophon’s dialogues portray Socrates discussing military training, strategy and tactics, with a level of knowledge that would more commonly be associated with the officer class. However, in the Laches, Plato also portrays Socrates being consulted by two generals seeking his advice about one’s sons undergoing training to fight in heavy armour.
Overall, Xenophon’s dialogues portray Socrates in a more down-to-earth manner than Plato’s, and they place greater emphasis on his strength of character and self-discipline. The Stoics were perhaps more influenced by that version of Socrates. We’re told, for instance, by Diogenes Laertius, that it was reading the second book of Xenophon’s Memorabilia that inspired Zeno, the founder of Stoicism, to become a philosopher. Indeed, Socrates, Antisthenes, and Xenophon, all of whom were known for their military service, would influence the later Stoic tradition.
Antigonus and his Circle (Hellenistic Athens)
The founder of Stoicism, Zeno, did not serve in the military as far as we know. However, his student, King Antigonus II Gonatas of Macedonia, was one of the most important military commanders of the period. He was a member of the Antigonid dynasty, descended from the successors of Alexander the Great. About seven years after the Stoic school was founded, in 294 BC, Athens was conquered by Demetrius I, Antigonus’ father, who also seized the throne of Macedonia, and went on to conquer most of Greece. Over the following years, Macedonia and much of the Greek territory was lost to rival rulers, and Demetrius died in 283 BC. However, in 277 BC, at the Battle of Lysimachia, Antigonus reconquered Macedonia and claimed the throne.
Antigonus was involved in many battles, with mixed success, but he did have a positive reputation for cultivating the arts. He attracted a circle of philosophers, mainly of the Megarian and Cynic schools, both important influences upon Zeno, the founder of Stoicism, whose follower Antigonus eventually became.
Antigonus also favoured him [Zeno], and whenever he came to Athens would hear him lecture and often invited him to come to his court. — Diogenes Laertius
Zeno was too elderly and frail by this point to travel from Athens to Pella, the capital of Macedonia. Instead he sent two of his favourite students, Persaeus and Philonides the Theban, and thus the Stoics became courtiers to Antigonus. When Zeno died, around 262 BC, Antigonus mourned him, saying that he had lost his favourite audience now the philosopher was gone. Antigonus then became a patron of the Stoic school, under its new head, Cleanthes, donating three thousand drachmas. As a very rough benchmark, a craftsman or a soldier in this period might earn on average about one drachma per day. So this is a huge sum of money, perhaps equivalent to half a million dollars today.
After Antigonus captured Corinth around 244 BC, he appointed Persaeus as Archon of the city. Persaeus died in 243 BC defending the city against an attack led by Aratus of Sicyon, the commander of the Achaean League. About a decade or so later, another of Zeno’s favourite students, Sphaerus, went to Sparta and became courtier to one of the two Spartan kings, Cleomenes III. He accompanied the king into exile in Egypt after Sparta was also defeated by Aratus of Sicyon n the Battle of Sellasia in 222 BC.
So although Zeno himself doesn’t appear to have been a soldier, one of his most famous students, Antigonus, was very prominent military leader of the period, and Stoics went to serve as advisors to King Antigonus and later to King Cleomenes, who was also engaged in war against the Achaean League.
The Scipionic Circle (Roman Republic)
After Zeno, as we’ve seen, Cleanthes became the head (“scholarch”) of the Stoic school, followed by Chrysippus, its most prolific author and greatest intellectual. They were followed by a series of scholarchs, one of the last being Diogenes of Babylon who, along with two other philosophers, took part in an embassy to the Roman Republic in 155 BC. Stoic philosophy appears to have naturally appealed to the Romans and it gradually became popular among their elite.
In particular, the Roman statesman and general Scipio Aemilianus (185–129 BC), also known as Scipio Africanus the Younger, became a student of the last scholarch of the Athenian Stoic school, Panaetius of Rhodes. Like Antigonus before him, Scipio surrounded himself with a circle of cultured intellectuals, including several other Stoics.
Scipio was one of the Republic’s most accomplished generals and lead Rome to victory over her great rival, Carthage, in the Third Punic War, ending in 146 BC with the total destruction of the city. Seneca lists Laelius the Wise, Scipio’s closest friend, and another student of Panaetius, as one of the philosophers he most admires, and Cicero would later portray Laelius discussing Stoic-sounding ideas in On Friendship. Moreover, in what was once one of the most celebrated passages in his writings, known as The Dream of Scipio, Cicero portrays Scipio Africanus experiencing a mystical vision, which the modern-day French scholar Pierre Hadot considered a striking example of the contemplative exercise he called “The View from Above.”
After Athens was sacked by the Roman dictator Sulla, in 86 BC, the Stoic school appears to have fragmented. It split into three branches according to one ancient author, Athenaeus, and the focus of its activity permanently shifts from Athens to Rome.
The next famous example of a Stoic who served in the military would be Cato the Younger, the notoriously stern political opponent of Julius Caesar. In 72 BC, Cato served in the Third Servile War, against the slave uprising started by Spartacus. Five years later, at the age of 28, he was then appointed military tribune, and given command of a legion in Macedonia. Cato was adored by the legionaries because his tough and highly-disciplined personal lifestyle was combined with humility. He dug trenches and built walls, ate military rations alongside his men, and shared their sleeping quarters. Whereas officers normally ride on horseback, Cato reputedly marched on foot alongside the legionaries under his command.
Cato fiercely opposed the rise to power of Julius Caesar, constantly warning that Caesar planned to make himself a tyrant over Rome, something the people greatly feared. In the end, when Caesar crossed the Rubicon river invading Rome, Cato was proven right. At first, during the Civil War, Cato refused to take sides, because he considered Pompey the Great, the general put in charge of the Republican army by the Senate, to be as much of a threat as Caesar.
However, after Pompey’s defeat, and death by poisoning, alongside Metellus Scipio, a relative of Scipio Amelianus, Cato took command of the shattered remnants of the Republican army in order to make a final stand at the fortified city of Utica in North Africa. Cato reputedly knew he couldn’t hope to win but rallied the troops to oppose Caesar and defend the freedom of the Republic as a matter of honour. However, Metellus Scipio’s army was slaughtered at the Battle of Thapsus in 46 BC. This effectively ended the Roman Republic, which Caesar now replaced with a dictatorship. Cato took his own life rather than be captured and used by Caesar for bargaining or propaganda.
Cato became a hero to generations of Romans, and to Stoics in particular. A century after his death, Seneca’s nephew, the Stoic poet Lucan, wrote an epic poem about the Civil War called The Pharsalia, in which Cato is portrayed, for want of a better word, as virtually a Stoic superhero. Indeed, in the 18th century, the playwright Joseph Addison’s Cato, a Tragedy, became very popular with the Founding Fathers of the United States. Benjamin Franklin quoted it in a letter and George Washington allegedly had the play performed for his army at Valley Forge.
Roman generals were typically granted a cognomen, an extra name, denoting the location of major military victory, such as the title Africanus (Scipio “of Africa”) given to Scipio Aemelianus after his conquest of Carthage in the region the Romans called Africa. However, as far as I’m aware, Cato is the only Roman commander to be granted a cognomen following a military defeat. He was given the title Uticensis (Cato of Utica) because he was perceived as having won a sort of lasting moral victory, which reverberated throughout Rome, despite giving his life and being defeated in the Civil War by Caesar.
One of the most memorable lines in Addison’s play relates to this and was quoted by George Washington to general Benedict Arnold:
It is not in the power of any man to command success; but you have done more — you have deserved it.
For Stoics, honour, or virtue, is more important than victory.
Augustus (Roman Empire)
Amid growing anxiety that he was planning to make himself not only dictator for life but King of Rome, Caesar was, of course, assassinated on the Ides of March, 44 BC. One of the lead assassins was Brutus, the nephew of Cato, and reputedly another Stoic, who had fought against Caesar, under Pompey in the Civil War.
Caesar’s death was followed by a prolonged period of civil war and political upheaval, during which several factions vied for control of the Republic. This came to a conclusion in 31 BC with the naval battle of Actium in which Octavian, Caesar’s adopted nephew, defeated the army of Mark Antony and his lover Cleopatra, the Queen of Egypt.
Sick of the conflict, the Romans were happy to grant Octavian more and more powers, in exchange for political stability, until he was eventually named Augustus and Princeps in 27 BC, effectively becoming the first Roman emperor. He went on to become one of Rome’s most militarily successful commanders, or imperatores.
At the start of his career, Octavian was known for his violent temper and reprisals against his political opponents. However, from his youth, Augustus had two well-known Stoic tutors, named Athenodorus Canaanites and Arius Didymus, who reputedly taught him to manage his temper.
The late Emperor Augustus also did and said many memorable things, which prove that he was not under the dominion of anger. — Seneca, On Anger, 3.23
At least according to Seneca, Augustus became more even-tempered in his old age. He would often quote the advice of philosophers in letters to his friends and family and even wrote a (sadly lost) book titled Exhortations to Philosophy. He also perhaps set the precedent for future generations of Roman nobles, in the imperial age, to study Stoic philosophy. This, of course, culminated, in the last famous Stoic of the ancient world: the Roman emperor Marcus Aurelius.
Unusually for a Roman noble of his station, Marcus had no military training or experience whatsoever, unless we count a passing reference to him being trained as a youth to fight in armour, while at Rome. Instead, his adoptive father, Hadrian’s successor, the emperor Antoninus, had him focus on his education and a bureaucratic career in the administration of Rome. Marcus excelled in this role and was a studious workaholic, immersing himself in rhetoric, philosophy, and the law.
Under Antoninus, Rome enjoyed a period of remarkable peace, and his dying word Aequanimitas, became emblematic of his reign. However, as soon as Marcus took to throne that all changed. The empire’s “barbarian” enemies had clearly been plotting for years and the Parthian king Vologases IV took the opportunity to invade the Roman client-state of Armenia, and then the Roman province of Syria, instigating the Parthian War.
As soon as he was acclaimed emperor, Marcus asked the senate to appoint his adoptive brother, Lucius Verus, as co-emperor, the first time Rome had ever had joint rulers of this kind, although Lucius was clearly in the subordinate role. Marcus was suffering from chronic health problems by this time — mainly chest and stomach pains — and being obviously more frail he delegated Lucius to assume responsibility for the legions. At the outbreak of the war, it was therefore Lucius who was sent to the east to assume operational command. Unfortunately, he was a hopeless gambler and alcoholic, who depended on his generals to fight the war. After initial setbacks, which unduly lengthened the war perhaps, Rome began making progress. Five years later, they had soundly defeated the enemy whose capital Ctesiphon was sacked by a young general called Avidius Cassius, forcing the Parthian king to sue for peace.
Unfortunately, the returning legionaries brought back the Antonine Plague, probably a form of smallpox, which they spread all across the empire, as they returned to their garrisons. Some scholars estimate that up to five million people died as a result. A massive coalition of northern tribes along the Danube frontier, led by the Marcomanni, seized the opportunity to invade and plunder the Roman provinces. They made their way down the Amber Route, across the Alps, and right into northern Italy, where they besieged the wealthy Roman city of Aquileia, throwing the city of Rome itself into a panic. Marcus no longer trusted Lucius to take sole command so this time they both set out for The First Marcomannic War.
However, Lucius dropped dead suddenly, perhaps from the plague, leaving Marcus sole emperor. With no military training or experience whatsoever, in the middle of a devastating plague, he now took command of the largest army ever massed on a Roman frontier — numbering approximately 140,000 men, including the auxiliaries and naval units sailing on the Danube. At first, it seems Marcus was viewed by some of his general with derision, with Avidius Cassius reputedly calling him nothing but a “philosophical old woman”. However, after initial setbacks, the Romans gradually defeated one enemy tribe after another, securing the frontier. We can see that Marcus’ legions came to revere him because, among other things, they even attributed two famous battlefield miracles to him. About six years on, he was now a respected general, and the veteran legions under his command were fiercely loyal to him.
However, just as Marcus was about to conclude the northern campaign, word reached his camp that his own general Avidius Cassius, had declared himself emperor in the east, instigating a civil war. Marcus rapidly prepared his troops to march southeast and engage the rebel army in Syria. However, remarkably, according to the historian Cassius Dio, Marcus responded by giving a famous speech before the legions, in which he pardoned everyone involved in the uprising, before battle had even commenced. When word of this reached Cassius’ legions, perhaps after some initial setbacks, they concluded there was no more reason to fight. However, Cassius would not step down. Two of his own officers therefore ambushed him and beheaded him, abruptly bringing the civil war to an end before it had even begun.
Marcus therefore managed to conclude a civil war, which threatened to split the empire, with virtually no bloodshed. He was true to his word, and pardoned those involved, apart from a few individuals involved in serious crimes, who were punished leniently. Marcus even protected the wife and children of Avidius Cassius. However, after his death, all of this was reversed by Commodus, who, seeking revenge, had Cassius’ family hunted down and burned alive as traitors.
Arrian and Rusticus
In his youth, Marcus had been given a thorough education in Stoic philosophy. His main tutor, Junius Rusticus, was a Roman statesman, who had allegedly served in the military, alongside Arrian of Nicomedia, the military governor of the Roman of Cappadocia, who successfully defended his province against the invading Alans. Indeed, Arrian was a highly accomplished Roman general and statesman and general, favoured and repeatedly promoted by the emperor Hadrian.
In addition to being a Roman statesman and general, Arrian was a prolific author, who modelled himself on and was even nicknamed after Xenophon(remember him?). He wrote several books on military training, strategy, and tactics, including The order of battle against the Alans. However, you may recognize his name because his writings also include the Handbookand Discourses of Epictetus. Epictetus himself wrote nothing. The books we normally attribute to him were in fact transcribed and edited by his student, Arrian of Nicomedia, who apparently saw himself very much as the Xenophon to Epictetus’ Socrates.
A generation later, Marcus Aurelius wrote of Junius Rusticus that “it was through him that I came to know the Discourses of Epictetus, as he lent me a copy from his own library” (Meditations, 1.7). Why does Marcus think it’s so noteworthy that this book came from Rusticus’ personal library? It appears to be more precious than a copy. It’s therefore tempting to wonder whether Rusticus received it in person from Arrian, during their military service together.
In a curious passage, written centuries later, the Roman orator Themistius writes that Scipio Africanus and Augustus, only consulted Panaetius and Arius Didymus about private matters, and did not “drag them into the stadium’s dust” of politics.
But this was not the experience of our current emperor’s fathers and the founders of his line [Hadrian, Antoninus Pius, and Marcus Aurelius], whose names are great. They pulled Arrian [of Nicomedia] and [Junius] Rusticus away from their books, refusing to let them be mere pen-and-ink philosophers. They did not let them write about courage and stay at home, or compose legal treatises while avoiding the public domain that is law’s concern, or decide what form of government is best while abstaining from any participation in government. The emperors to whom I am now alluding consequently escorted these men to the general’s tent as well as to the speaker’s platform. In their role as Roman generals, these men passed through the Caspian Gates, drove the Alani out of Armenia, and established boundaries for the Iberians and the Albani. — Themistius, 34th Oration
In other words, despite being philosophers, Arrian and Rusticus were committed to public life and had highly-accomplished military careers.
Donald J. Robertson is a writer and cognitive-behavioural psychotherapist. Author of How to Think Like a Roman Emperor: The Stoic Philosophy of Marcus Aurelius (2019)