Did Stoicism Condemn Slavery?

Massimo Pigliucci recently wrote an excellent article on Stoicism and slavery.  He was responding to a message, which said “I know that Epictetus was a slave and embraced Stoicism, but I find it difficult as an African-American to embrace this philosophy which is quite silent about slavery.”  Massimo mentioned in passing that “no Stoic questioned the very institution of slavery”.  This article looks at what the Stoics said about slave-owning.  There are some passages which suggest that Stoics may actually have questioned the institution of slavery or even stated that slave-owning was wrong but they’re not very well-known and there’s a bit of interpretation and reconstruction required.

In his History of Western Philosophy, Bertrand Russell quotes a passage in which Marcus Aurelius set forth the Stoic egalitarian political ideal.  Russell argues that although the Stoics could not realistically achieve this political goal in the ancient world, their ethical teachings ultimately inspired the emancipation of women and slaves via Stoicism’s lasting influence on Christian values:

This was an ideal which could not be consistently realized in the Roman Empire, but it influenced legislation, particularly in improving the status of women and slaves. Christianity took over this part of Stoic teaching along with much of the rest. And when at last, in the seventeenth century, the opportunity came to combat despotism effectually, the Stoic doctrines of natural law and natural equality, in their Christian dress, acquired a practical force which, in antiquity, not even an emperor could give to them. (History of Western Philosophy)

On the other hand, in contrast to Russell, some people question whether the ancient Stoics really did oppose the institution of slavery.

First of all, it’s worth noting that many people feel that the ancient Stoics should have viewed slavery negatively.  Why?  Well, consideration for others as our equals or fellow-citizens in the cosmos, ethical cosmopolitanism, is central to Stoic Ethics.  The Stoics were also firm believers in the concept of natural law and they agreed that no man is a slave by nature.  Some ancients believed, by contrast, that slavery was the natural state of certain races.  The view that some men are “natural slaves” is usually attributed to Aristotle and the Stoics are taken to have opposed him by rejecting the whole concept of natural slavery.   For instance, according to Seneca, Chrysippus defined a slave as a “hired-hand for life”, a man-made condition not a natural one (On Benefits, 3.22.1).

However, there are only a few scattered passages in the surviving literature where the question of slave-ownership is addressed explicitly.  There are also a handful of historical details and a few pieces of textual evidence, which can potentially be viewed as revealing Stoic attitudes toward slavery.   Nevertheless, I noticed recently that Diogenes Laertius, one of our main sources for early Stoic fragments, does appear to state that the founders of Stoicism condemned slave-owning as morally wrong.  Massimo extended his article above to acknowledge this passage in Diogenes “where he seems to suggest (second part) that the Stoics actually directly condemned slavery”.  In his summary of early Stoic Ethical doctrines, Diogenes writes of the Stoic wise man:

They declare that he alone is free and bad men are slaves, freedom being power of independent action, whereas slavery is privation of the same;  though indeed there is also a second form of slavery consisting in subordination [subjugation], and a third which implies possession of the slave as well as his subordination; the correlative of such servitude being lordship [slave-ownership]; and this too is evil.  (7.121-122)

I also checked my interpretation of this passage with John Sellars and Christopher Gill, two of my colleagues on the Modern Stoicism team.  Chris is emeritus professor of Ancient Thought at Exeter university and an authority on Stoicism, having published several academic books on the subject, including an analysis and commentary on the first half of The Meditations.  He agreed that “the passage does appear to say that slave-ownership is bad (not just the extended [metaphorical] forms of slavery normally discussed by Stoics)”, although it’s surprising to see an ancient author expressing this view.  John Sellars, an academic  philosopher and author of Stoicism and The Art of Living, pointed out that we might potentially expect the Stoics to “attack slavery in general as something unjust, especially given their cosmopolitan ambitions”.

Diogenes is mainly quoting sayings from Zeno and Chrysippus in this section, although he also refers to Apollodorus of Seleucia, a student of Diogenes of Babylon who wrote an important handbook on Stoic Ethics, around 150 BC.  He’s almost certainly referring to Zeno and Chrysippus here as “they”, probably based on summaries of their core teachings in Apollodorus and later authors, such as Arius Didymus.

Here are a couple of interesting references to that passage…  In his Histoire des théories et des idées morales dans l’antiquité (1879), Jacques François Denis cites the passage above from Diogenes Laertius and interprets it as follows:

There is, says Zeno, such slavery that comes from conquest, and another that comes from a purchase: to one and to the other corresponds the right of the master, and this right is bad. (p. 346)

The American author Robert G. Ingersoll, famous for being an early proponent of agnosticism, cites Denis’ comment on the same passage, remarking:

I read Zeno, the man who said, centuries before our Christ was born, that man could not own his fellow-man.  “No matter whether you claim a slave by purchase or capture, the title is bad.  They who claim to own their fellow-men, look down into the pit and forget the justice that should rule the world.”  (Why I am an Agnostic)

The first sentence is a paraphrase of the passage in Diogenes Laertius, although the second appears to be derived from the Epictetus passage  quoted below (Discourses, 1.13).

As Denis and Ingersoll observed, the passage in Diogenes Laertius is most likely derived from a saying of Zeno, or possibly Chrysippus.  Crucially, as they both note, it identifies two ordinary meanings of “slavery”: capture and purchase.  (This is important for reasons we’ll return to later.)

In addition, though, it also distinguishes these from the special technical sense in which the word is used in the Stoic paradoxes, to refer to the lack of inner freedom.  So actually the passage in Diogenes distinguishes three senses of the word “slavery”:

1. The sense in which the majority of people (bad men) are enslaved to their passions and externals, in contrast to the inner freedom of the ideal Stoic Sage
2. The forced subjugation (ὑπόταξις) of one person to another, e.g., capture and enslavement by pirates or brigands or by enemies in war
3. The legal possession of a slave as property, i.e., through purchase, which entails their capture and forced subjugation (or that of one of their ancestors)

The passage above goes on to say that the correlate of such enslavement (items 2 and 3) is despoteia (δεσποτεία) which most definitely means slave-ownership in the Greek original, although translated into English here more vaguely as “lordship”.  He then adds in “and this too is evil” (phaule, φαύλη), which means wretched, base, immoral, etc., a term used as a synonym for vice in Stoic Ethics.  Indeed, throughout the chapter, Diogenes employs this same term very frequently (about eighteen times!) as a synonym for vice.  I don’t think there can be any question that he means slave-ownership is morally wrong.

As we’ll see below, when comparing this passage with the discussion of slavery in another Stoic text, by Dio Chrysostom, Zeno (or possibly Chrysippus) appears to have argued that slaves are either purchased or captured; capturing slaves is theft, and unjust, because no man is born a natural slave; but purchased slaves must either have been captured in the past or are descendants of those who have been captured; therefore all enslavement is unjust, because it’s a form of robbery, or the theft of a man from his natural state.  Ingersoll and Denis both read this passage in the same way.

Some people boldly claim that it was totally unheard of to question the institution or practice of slavery in the ancient world.  They’re most definitely wrong about this, though.  The Sophist Alcidamas of Elaea, a student of Gorgias who flourished in the fourth century BC, was probably the first thinker in Athens to do so.  He wrote “God has left all men free; Nature has made nobody a slave”.  Around the same time, Socrates is also portrayed by Xenophon as stating that the capture and enslavement of free men (andrapodizo) is a form of injustice (adikia), a vice.   His student Euthydemus even says it would be “monstrous” to refer to the capture of slaves as “justice” (Memorabilia, 4.2.14).  However, Socrates goes on to qualify this by saying that if an elected general enslaves a city that could be considered just if the city itself were behaving in an unjust and hostile manner.  So he believed that enslavement of conquered aggressors was acceptable.  Plato portrays Socrates exhibiting a slightly different attitude toward slavery in Book Five of The Republic, where he says that the ideal state would never enslave other Greeks, but only barbarian races.

These accounts of Socrates’ attitude toward slavery conflict, and both show him endorsing enslavement under certain circumstances.  However, what they do have in common is the suggestion that the circumstances in which many slaves were captured are fundamentally unjust.  Albeit in their own limited way, these comments may have raised quite penetrating questions about the institution of slavery in general.  They certainly prove that Greek philosophers were capable of drawing the radical conclusion that some common forms of slave capture were unjust.

By contrast, others, such as Aristotle, argued that some people are slaves by nature.  He wrote that:

[…] those who are as different [from other men] as the soul from the body or man from beast—and they are in this state if their work is the use of the body, and if this is the best that can come from them—are slaves by nature. For them it is better to be ruled in accordance with this sort of rule, if such is the case for the other things mentioned. (Politics, 1)

The Stoics, probably adopting arguments forwarded by much earlier authors, categorically rejected the notion that any human being is naturally born to be a slave.   (With the possible exception of the Middle Stoic, Posidonius, who embraced elements of Aristotelianism and appears to have reintroduced the notion of natural slavery.)  Zeno argued that all men should ideally live together as though in a common herd.  Chrysippus’ definition of a slave as a “hired-hand for life”, a social contract based solely on their purchase, is usually interpreted as an explicit rejection of the Aristotelian theory that some people are slaves by nature.

However, the injustice of capturing and enslaving someone who is naturally free-born is perceived as infecting and undermining the whole institution of slavery, as we’ll see.  (Some authors believe that Antisthenes’ earlier book Of Freedom and Slavery may have contained similar arguments, which potentially influenced the Cynic-Stoic tradition.)

Zeno of Citium

Zeno’s Republic, arguably the founding text of Stoicism, was a scathing critique of Plato’s book of the same name.  In it Zeno argued in favour of an ideal political state in which all men and women would be equal, living like brothers and sisters in a single community. According to Lactantius, an early Christian author, the Stoics said that both women and slaves should be taught philosophy, because he says they saw no difference between their capacity for wisdom and that of free men.  This is very clearly a rejection of Aristotle’s notion of natural slavery.

Moreover, the much-admired Republic of Zeno, the founder of the Stoic sect, may be summed up in this one main principle: that all the inhabitants of this world of ours should not live differentiated by their respective rules of justice into separate cities and communities, but that we should consider all men to be of one community and one polity, and that we should have a common life and an order common to us all, even as a herd that feeds together and shares the pasturage of a common field. (Plutarch, On the Fortune or Virtue of Alexander)

Now in the few fragments that survive there’s nothing explicitly referring to the role of slaves in relation to Zeno’s Republic.  However, it seems to stand to reason that if everyone is equal, like brothers and sisters (one flock or herd), and each has equal rights then there can be no slaves.  Also, as slaves are property, if all property is held in common then there could arguably be no slaves.  (And without law courts, it would also be impossible to administer laws governing slave-ownership.)  So it does seem impossible that slaves could have been envisaged as forming part of the ideal Stoic Republic.  Of course, that’s an ideal and not advice for real world politics.  Nevertheless, it is supposed to denote what Zeno considered to be a good society, and the social goal of Stoicism.  Slavery must have been abolished in the Stoic Republic described by Zeno.

Some people have taken the following anecdote from Diogenes Laertius to imply that Zeno owned a slave:

We are told that he was once chastising a slave for stealing, and when the latter pleaded that it was his fate to steal, “Yes, and to be beaten too,” said Zeno. (7.23)

However, this passage makes a point of saying “a slave” not “his slave” – there’s nothing in it to suggest that Zeno was the owner of the slave in question, it’s more likely that it refers to someone else’s slave.  At least according to one account, Zeno lost his fortune at sea and subsequently lived like a beggar, as follower of the Cynic Crates, and he continued in a similar austere lifestyle after founding the Stoic school.  If he had no property, he’s unlikely to have owned slaves.  The Cynic way of life is generally taken to involve renunciation of wealth, and by implication slaves.  According to tradition, the true Cynic only owns what he can fit in his satchel – which would presumably have insufficient room for a slave!

Moreover, Zeno was a metic or foreign resident of Athens, not an Athenian citizen.  As such he had few rights, and his status was somewhat between that of a slave and a citizen.  Technically, foreign residents could own slaves, by law, but they could not own property.  So unable to own his own home, Zeno appears later in life to have lived as the household guest of his student Persaeus.  Without property at Athens, though, it seems unlikely that Zeno would have owned slaves.  Indeed, Seneca says that it was well-known in his time that Zeno had no slaves:

It is well known that Homer had one slave, that Plato had three, and that Zeno, who first taught the stern and masculine doctrine of the Stoics, had none: yet could anyone say that they lived wretchedly without himself being thought a most pitiable wretch by all men? (Consolation to Helvia, 12)

There is another interesting anecdote in Diogenes Laertius, incidentally, in which Zeno appears to rebuke another man for beating his slave:

Once when he saw the slave of one of his acquaintance marked with weals, “I see,” said he, “the imprints of your anger.” (7.23)

As we’ve seen, Zeno introduced the convention that all those who are not virtuous are called “slaves”, in a technical sense.  The Stoics believed that only the ideal Sage is truly virtuous and neither Zeno nor the other founders of the school claimed to be perfect.  So this effectively means that all men are “slaves” to their passions, through attachment to externals.  In the Discourses of Epictetus, for this reason, we can see him repeatedly addressing his students, collectively, as slaves.

Elsewhere, Diogenes Laertius says the early Stoics distinguished between evils insofar as they were means or ends.  Among evil ends, things that are inherently evil, he clearly lists “slavery” and “every vicious action”.  Thus slavery is an intrinsically bad activity which participates in a vicious attitude of mind.  However, in this instance, he may be referring to “slavery” in the sense of the Stoic paradoxes, i.e., the inner state of enslavement to our passions.

Lucian

The satirist Lucian, a contemporary of Marcus Aurelius, describes the Stoic Republic as a Utopian ideal toward which men should strive, even though it’s a distant goal.  He describes it as follows in his dialogue Hermotimus, or the Rival Philosophies.

[…] all the citizens are aliens and foreigners, not a native among them; they include numbers of barbarians, slaves, cripples, dwarfs, and poor; in fact any one is admitted; for their law does not associate the franchise with income, with shape, size, or beauty, with old or brilliant ancestry; these things are not considered at all; any one who would be a citizen needs only understanding, zeal for the right, energy, perseverance, fortitude and resolution in facing all the trials of the road; whoever proves his possession of these by persisting till he reaches the city is ipso facto a full citizen, regardless of his antecedents. Such distinctions as superior and inferior, noble and common, bond and free, simply do not exist there, even in name.

Education in philosophy was  often seen as the province of wealthy, aristocratic young men.  However, this makes it clear that the Stoic school is unusual in accepting absolutely anyone, foreigners like Zeno himself and the other scholarchs, cripples or slaves like Epictetus, the rich or poor such as Cleanthes, and, though he doesn’t mention it here, they were also known for admitting both men and women.  The famous daughter of Cato of Utica, for example, Porcia Catonis, was portrayed by Plutarch as a Stoic.

All distinctions between superior and inferior, slave or free, being abolished from this Republic, and slaves being admitted, it appears once again that the Stoic ideal musts involve the abolition of slavery.

Seneca

In Letter 31, Seneca makes it clear that the human soul is equally divine whether it exists in a Roman knight or a slave:

What else could you call such a soul than a god dwelling as a guest in a human body? A soul like this may descend into a Roman knight just as well as into a freedman’s son or a slave. For what is a Roman knight, or a freedmen’s son, or a slave? They are mere titles, born of ambition or of wrong.

So, once again, you’d think that, in principle, would lead him to conclude that slavery is immoral.  Seneca wrote a Letter to Lucilius entitled On Master and Slave (Letter 47).  In it he emphasised that for Stoics slaves are first and foremost our fellow-humans.

“They are slaves,” people declare.  Nay, rather they are men.  “Slaves!”  No, comrades.  “Slaves!”  No, they are unpretentious friends.  “Slaves!”  No, they are our fellow-slaves, if one reflects that Fortune has equal rights over slaves and free men alike.

Seneca owned slaves himself.  However, his writings were arguably aligned more with the Middle Stoa.  As we’ve seen, some Middle Stoics, influenced by Aristotelianism, may have reintroduced the notion of natural slavery.  Stoics who were more aligned with Cynicism, like Musonius, Epictetus, or Marcus Aurelius, though, are likely to have questioned the concept of natural slavery, or rejected it outright, and to have been more influenced by the early Stoicism of Zeno’s Republic.

Seneca does condemn cruelty toward slaves in this letter but doesn’t go so far as to condemn the institution of slavery.  He does, however, repeatedly emphasis that slaves should be treated with respect, as fellow-human beings, and not as inferiors.

Kindly remember that he whom you call your slave sprang from the same stock, is smiled upon by the same skies, and on equal terms with yourself breathes, lives, and dies. It is just as possible for you to see in him a free-born man as for him to see in you a slave.

At one point he even seems to acknowledge that he’s skirting around the more fundamental ethical and political questions about slavery.

I do not wish to involve myself in too large a question, and to discuss the treatment of slaves, towards whom we Romans are excessively haughty, cruel, and insulting. But this is the kernel of my advice: Treat your inferiors as you would be treated by your betters.

It’s tempting to read this as expressing Seneca’s awareness of a tension between Stoic ethics and the prevailing norms of Roman society.  He realizes that Stoic ethics teaches us to treat all humans, even slaves, as our equals, as fellow-citizens of the cosmos.  However, he doesn’t want to rock the boat too much by questioning the whole institution of slavery.  At least, that’s one way of reading his comments on the subject.

Epictetus

Epictetus, of course, was originally a slave himself, but gained his freedom later in life.  In fact his name just means “acquired” and seems to have been a nickname of sorts, denoting the fact he was the property of another man.  In one of the fragments attributed to him he appears to condemn slave-owning:

What you avoid suffering yourself, seek not to impose on others. You avoid slavery, for instance; take care not to enslave. For if you can bear to exact slavery from others, you appear to have been yourself a slave. For vice has nothing in common with virtue, nor freedom with slavery. As a person in health would not wish to be attended by the sick nor to have those who live with him in a state of sickness ; so neither would a person who is free bear to be served by slaves, nor to have those who live with him in a state of slavery. (Epictetus, Fragments)

In one of the shorter Discourses, Epictetus also directly addresses slave-ownership.  In response to a question about acting acceptably to the gods, Epictetus refers to a slave-owner becoming furious because his slave brought him water that was tepid and not warm enough.

Slave yourself, will you not bear with your own brother, who has Zeus for his progenitor, and is like a son from the same seeds and of the same descent from above? But if you have been put in any such higher place, will you immediately make yourself a tyrant? Will you not remember who you are, and whom you rule? that they are kinsmen, that they are brethren by nature, that they are the offspring of Zeus?—But I have purchased them, and they have not purchased me. Do you see in what direction you are looking, that it is towards the earth, towards the pit, that it is towards these wretched laws of dead men? but towards the laws of the gods you are not looking.  (1.13)

Here Epictetus reminds his wealthy students that even their slaves should be viewed as brothers as they are all children of Zeus.  The role of Zeus as father of mankind is a common theme in Stoicism, and the wise man is directed to emulate Zeus by viewing the rest of mankind as his brothers and sisters, without discrimination.  If you have been put in the position of ownership over another man you must nevertheless remember that he is your kinsman, in the eyes of Zeus.  In response to a student objecting “but I have purchased them”, quite astoundingly, Epictetus refers to the Roman laws governing slave ownership as “these wretched laws of dead men”, i.e., mortals, and scolds his students for appealing to them rather than giving precedence to the eternal laws of Nature or Zeus.  Calling the laws governing slave-ownership “wretched”, clearly implies a criticism of the legal institution of slavery, although Epictetus doesn’t really elaborate further on this point.

Incidentally, Epictetus’ teacher, Musonius Rufus, had said that slaves are entitled to disobey masters who instruct them to engage in immoral actions (Lecture 16).  He also said that like Diogenes the Cynic, who was himself captured and sold into slavery by pirates, a slave may not only be the equal of but actually more virtuous than his master (Lecture 9).

Dio Chrysostom

Perhaps our clearest articulation of the Stoic position on slavery actually comes from Dio Chrysostom.  Dio wasn’t a fully-fledged Stoic but rather an eclectic philosopher and orator, influenced both by Stoicism and Cynicism.  He was student of the great Stoic teacher Musonius Rufus, friends with the Stoic Euphrates of Tyre, and probably also an acquaintance of Epictetus.  Marcus Aurelius appears to mention both Dio and Euphrates favourably in The Meditations.

Dio provides one of our most explicit Stoic-influenced condemnations of slavery in his fourteenth and fifteenth orations On Slavery and Freedom: Discourses I and II.  He starts off his initial Discourse by forwarding typical arguments in favour of the Stoic paradox that only the wise man is truly free and the majority of us are slaves because of our ignorance.  This is the special Stoic technical use of the word “slavery”, and refers to our inner state.  As Dio notes, this paradox means that even the great king of Persia, Xerxes, may have been a slave inwardly, to his ignorance and passions, despite his external power; and even someone who appears outwardly enslaved, such as Diogenes the Cynic, might nevertheless be inwardly regal and free, if he possesses virtue and wisdom.  (These arguments and the terminology used by Dio are clearly Stoic in nature and acknowledged as such by modern commentators.)

However, in the second Discourse, Dio proceeds to discuss the ordinary sense of the word “slavery”, i.e., the forced subjugation or legal possession of one person by another.  He argues that all slaves are either captured or are the descendants of those who have been captured.  In the same way that a person can possess land, property, or livestock for a long time but nevertheless unjustly,  says Dio, to capture men in war or by brigandage is “to have gained possession also of human beings unjustly”.  Slaves can also be purchased, inherited, or born into the household as the children of other slaves but all these depend on this earliest method of acquiring slaves by capture, which Dio says “has no validity at all” and constitutes “unjust servitude”.

Those individuals who were initially compelled by force into a life of servitude should not even be termed “slaves”.  Therefore all slavery is “unjust” insofar as it depends, ultimately, on the capture of individuals who were born free.

If, then, this original mode of acquiring slaves, from which all other modes derive their existence, be destitute of justice, none of them can consequently be deemed just; nor can a single individual either be a slave in reality, or be truly and substantially discriminated by such an appellation. (15.26)

Dio repeatedly denies that being captured can legitimately make someone who is free-born into a slave and asserts that this means their descendants cannot be slaves either.  Note that the distinction he employs in this oration between inner slavery, slavery by capture, and slavery by purchase, appears to reflect the distinction made by the Stoics, according to Diogenes Laertius, in the passage cited above, which Denis and Ingersoll plausibly attributed to Zeno.  It seems certain that Dio Chrysostom and Diogenes Laertius are both ultimately drawing upon the same Stoic source in making this distinction and the two texts shed some light on each other.

The presence of the passage in Diogenes also appears to confirm the conclusion of modern scholars that these orations of Dio are thoroughly Stoic in nature.  Likewise, Dio’s discourses confirm that the Stoics meant phaulos (bad or wretched) to mean unjust or morally wrong.  They also clarify that the Stoics are talking about the distinction between slaves who are captured and subjugated by force, usually during warfare but also by bandits or pirates, and slaves who are legally purchased.  Their point is that both practices are unjust, and immoral, because the purchase of a slave depends on the fact that they or their ancestors were at some point captured by force, or stolen from their natural state.

Marcus Aurelius

As we’ve seen, the Stoics believed in the ideal of ethical cosmopolitanism.  All humans, in fact all beings that possess reason, are equally citizens of the same cosmos.  This doctrine is arguably incompatible with slavery, as for cosmopolitans everyone is a citizen, and citizens are not slaves.  Moreover, no man is naturally born to be enslaved.  This theme is particularly prominent in The Meditations of Marcus Aurelius, where it’s closely associated with his pantheistic view of Nature.

Marcus’ therefore expressed his political vision as a state with a mixed constitution for which the freedom of its subjects is its highest priority:

[…] the idea of a balanced constitution, and of government founded on equity and freedom of speech, and of a monarchy which values above all things the freedom of the subject (1.14)

C.R. Haines quotes from an imperial rescript attributed to Marcus, which likewise reads: “Let those who have charge of our interests know that the cause of liberty is to be set before any pecuniary advantage to ourselves.”  Another one states: “It would not be consistent with humanity to delay the enfranchisement of a slave for the sake of pecuniary gain.”

Sometimes people object that although Marcus was emperor he didn’t abolish slavery.  That seems very obviously to be an unrealistic expectation, though.  The position of Roman emperor was far too precarious for that sort of radical social upheaval.  The Roman economy completely depended on slave labour.  Moreover, when foreign enemies were defeated, tens of thousands were normally captured.  Often the only realistic option was to keep them as slaves.  If they were returned to their lands, they would simply regroup and attack again.  So the Romans could plausibly argue that enslavement was a more ethical option than mass executions, or genocide, of enemy tribes.

However, Marcus did try to resettle thousands of Germanic tribesman within Italy.  This wasn’t entirely successful as some were involved later in uprisings.  The Historia Augusta actually tells us that Marcus observed the principles of justice even in dealing with captive enemies, choosing to resettle them.  This could be read as implying that Marcus believed enslaving them would have been an injustice.

He scrupulously observed justice, moreover, even in his dealings with captive enemies. He settled innumerable foreigners on Roman soil. (Historia Augusta)

He also caused widespread unrest at Rome by granting thousands of slaves their freedom in exchange for joining the legions during the crisis of the initial Marcomannic invasion, when the armies were severely depleted by the Antonine Plague.

Moreover, as his biographers have observed, Marcus consistently appears to have taken legal steps to improve the rights of slaves in relation to manumission, or obtaining their freedom. For instance, Birley observes that in an official reply to a query put to him by his lifelong friend Aufidius Victorinus, Marcus gave a ruling improving the rights of slaves to manumission, cited nearly twenty times in the surviving legal anthologies. Most often they say “He attains his liberty in accordance with the ruling of the Deified Marcus”, referred to as the “law of liberty”, although the ruling is not quoted in full. Birley concludes that despite the “harsh realities” of Rome’s slave-labour economy:

…it is fair to say that Marcus’ attitude, as revealed not only by the much-quoted reply to Victorinus, but by other decisions made earlier in his reign, was one of deep compassion for the position of individual slaves, and that he did take some steps to improve their position. (p. 200)

It’s true that these were very gradual changes but Marcus himself states that he has to be satisfied with small steps in the right direction politically.  In case there’s any doubt about the delicate balance of power during his reign, it’s worth noting that Marcus actually faced a full-scale civil war in 175 AD, reputedly triggered in part because of unrest over the leniency of his attitudes.  The uprising was put down very quickly but it proves that Marcus couldn’t just do what he liked politically, he faced an opposition faction in the senate and potential usurpers waiting in the wings.

Marcus wrote that he was inspired by learning about Stoic Republicans like Cato of Utica and Thrasea and that he aspired to the political ideal of “a balanced constitution, and of government founded on equity and freedom of speech, and of a monarchy which values above all things the freedom of the subject” (1.14).  This is a remarkable passage.  It sounds reminiscent in some ways of Zeno’s Republic, which was written almost 500 years earlier.  It also seems difficult, obviously, to reconcile the institution of slavery with the ideal of a state that makes its highest priority the freedom of its subjects.

Moreover, in The Meditations, Marcus also wrote:

A spider is proud when it has caught a fly, and one man when he has caught a little hare, another a little fish in his net, another boars, another bears, and another some Sarmatians. Now if you look into their judgements, are these not simply brigands? (10.10)

This is a remarkable passage.  Marcus is referring to the capture of enemy Sarmatian soldiers during the Marcomannic Wars, mainly by his own Roman officers.  These captives would potentially have been ransomed or sold into slavery.  The eminent French scholar Pierre Hadot comments on this passage:

The war in which Marcus defended the borders of the empire was, for him, like a hunt for Sarmatian slaves, not unlike a spider’s hunt for flies. (Philosophy as a Way of Life, p. 185)

Marcus compares the capture of barbarian slaves to catching fish in a net, hunting boar, and so on, but then astoundingly he concludes that the character of a person who takes pride in doing this is no better than that of a brigand or robber.  In other words, perhaps in an allusion to the Stoic doctrine mentioned in Diogenes Laertius and Dio Chrysostom, he appears to be saying that capturing enemy soldiers is a form of theft, robbing them from their natural state of freedom.  He doesn’t go on to say, as the early Stoics did, that this vitiates the institution of slavery insofar as all legally purchased slaves must have been at one time captured, or are the descendants of those who have been.

This passage is also strikingly similar to the Stoic argument against slavery forwarded by Dio Chrysostom.  Some philosophers believed certain individuals, even certain races, were naturally born to be slaves.  The Stoics categorically rejected this notion.  Marcus here clearly rejects the idea that the Sarmatians are natural slaves.  As they’re freeborn, capturing them is simply unjust, or akin to robbery.  In other words, this passage is clearly a rejection of the assumption that so-called barbarian races are “fair game” for enslavement.

Moreover, Marcus appears to have caused some unrest at Rome by offering many slaves, including gladiators, their freedom in exchange for joining the legions.

And since the pestilence [the Antonine Plague] was still raging at this time, he […] trained slaves for military service — just as had been done in the Punic war — whom he called Volunteers, after the example of the Volones.  He armed gladiators [likewise slaves] also, calling them the Compliant, and turned even the bandits of Dalmatia and Dardania into soldiers. (Historia Augusta)

Marcus’ Legislative Measures

Birley, who provides the most academically authoritative biography of Marcus Aurelius’ life, writes of the evidence regarding his legislative agenda:

In all the legislation preserved three major interests are apparent. The first is the question of the ‘manumission’ – liberation – of slaves; the second is the appointment of guardians for orphans and minors; the third is the selection of councillors (decuriones) to run the affairs of local communities throughout the provinces.

Later, Birley remarks:

This interest in giving any slave the maximum possible chance of attaining his freedom, if there had ever been any question of his master wishing to grant it, was a matter which Marcus was concerned with throughout his reign, and towards the end of it, a decision he made, in a case involving manumission brought to his attention by his friend Aufidius Victorinus, was to be constantly cited by the jurists as the decisive precedent.

The rights of slaves were generally improved throughout Marcus’ reign. Indeed, it was Antoninus Pius, with Marcus serving as his right-hand man, who first decreed that owners should stand trial for the murder of slaves, granting them protection under the law in that regard for the first time.

The French jurisconsult, Firmin Laferrière, reviewed the influence of Stoic philosophy on Roman law in The influence of Stoicism on the doctrine of the Roman jurisconsults (1860). With regard to slavery he observed of the Stoics:

As interpreters of the laws, jurisconsults were obliged to submit to an institution established in the civil law of Rome and other peoples; but they placed in their writings the maxim of natural law next to the civil institution, as a perpetual and morally superior teaching, and they tried to soften the condition of slaves by the influence of feelings of humanity, or to transform it into a free condition by changes in jurisprudence: Quod attinet ad jus civile, servi pro nullis habentur, non tamen et jure naturali. [As it concerns civil law, slaves are regarded as nobodies; this is not the case, however, in natural law.]

Laferrière, p. 26

Noyen (‘Marcus Aurelius: The Greatest Practician of Stoicism’,1955) undertook a detailed analysis of Roman juridical texts in relation to Marcus Aurelius and found 324 references to texts by him or about him. The majority refer to the rights of women, children and slaves. Noyen goes so far as to conclude from his reading of these texts:

The slaves and the freedmen, about whom we possess some sixty laws, constitute the lion’s share in Marcus’ legislature. The latter is completely dedicated to the “favor libertatis“, and makes us think, however daring this opinion may seem, that Marcus, faithful to his Stoic principles, aimed at the complete abolition of slavery.

Noyen, p. 376

Paul Barron Watson’s excellent biography of Marcus Aurelius contains a very detailed account of the specific legislative changes that Marcus enacted in order to improve the rights of slaves. It’s about twelve pages long. I’ll quote some key passages at length below but you’ll have to consult the original for the numerous examples he cites regarding specific pieces of legislation. He opens with the conclusion:

The broad and charitable attitude which men were beginning to take with reference to the rights and duties of the various portions of society can be due only to the principles of Stoicism, which were forcing themselves upon the minds of men […] In no way was this breadth of purpose more marked than in the laws which Marcus passed in aid of slaves. […]

In addition, therefore, to the feelings of benevolence which actuated Marcus Aurelius in relieving this down-trodden class of society, he was induced by political reasons to enact measures to avert the impending danger [of slave revolts]. How to augment the relatively small free population and how to alleviate the distress of the slaves and freedmen, were problems which Marcus kept continually before him. He strove to make real that idea which he speaks of in his Thoughts [i.e., The Meditations] — the idea of a “polity in which there is the same law for all, a polity administered with regard to equal rights and equal freedom of speech, and the idea of a kingly government which respects most of all the freedom of the governed.”

It was a difficult task that lay before the Emperor. Revolutions sometimes take place in politics — in law, never. The boast of law is that it is founded on justice; and the principles of justice remain eternally the same. The principles of political parties may be overthrown by the weight of numbers or the power of wealth; in law, whatever alterations are accomplished are effected by force of argument alone. To convince the Roman people that a person taken in war is not the property of the captor was more than any one emperor could accomplish. Marcus Aurelius did a noble work-in promulgating this doctrine; but its final adoption could only be effected by the reasoning of ages. As a first step towards the abolition of slavery Marcus introduced a practice which was, in fact, almost a logical consequence of his immediate predecessors’ beneficent laws. [Hadrian had introduced basic rights for slaves by declaring that a master could not kill their slave without just cause.]

Marcus Aurelius was quick to perceive the advantage which had thus been gained; and he at once followed it up by an enactment, framed as a privilege to the master, but in reality a decided benefit to the slave. By this new law the master was empowered to bring an action in the courts for every injury suffered at the hands of his slave.1 Thus the masters were encouraged to lay all their grievances before the tribunals instead of taking the punishment of their slaves into their own hands, as they had done hitherto. It was one step more towards placing both upon the same footing. If the masters could be induced to rely on the courts to award them justice for all injuries from their slaves, it would follow almost as a corollary that the slaves might look to the courts for protection from the injustice of their masters. It is always the oppressed that gain when law is substituted in the place of despotism. A secondary purpose which Marcus had in encouraging masters to lay their grievances before the courts was to do away with a brutal custom known as the quaestio, or torture. This had long been the ordinary way of inducing a slave to confess any crime which he had committed, and also of compelling him to furnish evidence against his fellows. It was a method which failed chiefly in the uncertainty of its result. […]

Even Marcus Aurelius seems to have aimed rather at substituting a more just method of obtaining evidence than at abolishing entirely the older form of procedure. To his cred it, however, it should be said that he urged strongly the propriety of resorting to this method only as a last resource, and even then of using as little violence as possible. Indeed, the compilers of the Digest have preserved a letter in which Marcus recommends that a slave who, under torture, had confessed a crime of which he turned out afterwards to be innocent, should be set at liberty, in recompense for the indignity he had suffered.’

Another humane law, by which Marcus re-strained the cruelty of masters, provided that if a slave should be sold, otherwise than after judgment in the courts, for the purpose of being pitted against beasts in the arena, both the seller and the buyer should be punished.’ As long, however, as the masters were just and kind towards their slaves, the Emperor felt that the slaves were, in return, bound to obey their masters. He therefore published an open letter, in which he proclaimed it to be the duty of all governors, magistrates, and police soldiers to aid masters in their search for fugitive slaves. When found, the runaways were to be returned to their masters, and whoever aided in concealing them was to be punished.’ Indeed, Marcus went further ; and made it lawful for the search to be conducted upon the estates of the emperor as well as upon those of senator or peasant.’

It was not only, however, with a view towards relieving the condition of those in actual slavery that Marcus worked, he sought, also, to render enfranchisement more easy. [Watson recounts several specific legislative changes made by Marcus to increase the rights of slaves to manumission; for example:] In cases where a slave was sold or given away, to be manumitted at the death of the recipient, Marcus insisted, with the utmost imperativeness, that the manumission must be performed. Nothing was allowed to stand in the way.’

The condition, too, of slaves who had already received their liberty, Marcus attempted to alleviate. [Again, several legal examples are provided.] In all doubtful cases with regard to slaves and freedmen Marcus preferred to fail on the side of charity rather than to encourage cruelty; and we hear of some in stances where he even went so far as to allow a freedman to be chosen as tutor to his infant patron. One law more we must notice before leaving the subject of slavery. It is set forth in a rescript of Marcus Aurelius, and reflects clearly the benevolent principles which actuated the Emperor in all his public life. The aim of the law was to prevent masters who had stipulated with their slaves that they should be freed if they performed such and such services before a certain time, from evading their contract.

Marcus adds to this final rescript: “for principles of humanity demand that a money consideration shall never stand in the way of a person’s freedom”. (86-97)