Three Unorthodox Stoics

An outline of three major heterodox Stoics who appear to have abandoned the orthodox teachings of Zeno, and in at least one case to have left the Stoic school.

Gem-Zeno-British-MuseumIn a nutshell…

One of the recurring questions that comes up in discussion forums is “What’s an ‘orthodox’ Stoic?”  I think most modern scholars would say that, first and foremost, it’s someone who believes that “virtue is the only true good”, as Cicero put it.  However, one of the main sources for our knowledge of early Stoicism, Diogenes Laertius, sheds some further light on this question.  He provides three examples of important students of Zeno, the founder of Stoicism, who broke from the orthodox Stoic teachings of Zeno.  They changed their own beliefs in ways that caused them to be labelled “heterodox” and perhaps in some cases even caused them to split from the Stoic school completely, to go their own way, or join another school of philosophy.

  1. Aristo of Chios, discounted the value of studying Physics and Logic, believing Ethics to be the sole concern of philosophy.  He also argued that apart from virtue and vice, everything else is completely “indifferent”, seemingly rejecting the Stoic doctrine of “preferred” indifferents.  He sounds like someone leaning toward the older Cynic teachings.
  2. Herillus of Carthage, who argued that knowledge (episteme) in general was the true goal of life, rather than virtue, or knowledge specifically of the nature of the good.  However, he also seems to have argued that there are two fundamentally separate goals in life: the attainment of scholarly and scientific knowledge achieved only by the wise, and a “sub-goal” apparently pertaining to fulfilling one’s social and familial duties, which even the unwise could pursue.  The Stoics, by contrast, argued that the only goal is moral wisdom or virtue, and that this inherently entails acting for the welfare of others.  Herillus perhaps came to resemble the Academics or Aristotelians more than the Stoics, and may have been viewed as going to the opposite extreme compared to Aristo, in his arguments against Zeno.
  3. Dionysius of Heraclea, who disagreed with Zeno after suffering from a painful eye-infection, which led him to conclude that pleasure (hedone), and presumably the avoidance of pain, was the true goal of life rather than virtue.  He left the Stoa to join the Cyrenaic school, although this dispute perhaps prefigures the long-running arguments between the later Stoics and Epicureans.


One of our main sources for the teachings of the early Stoics is The Lives and Opinions of Eminent Philosophers by Diogenes Laertius.  The organisation of the book is particularly interesting with regard to Stoicism.  Book Six of the Lives concerns the Cynics and begins with a chapter on Antisthenes, followed by chapters on Diogenes of Sinope, Crates, and several other Cynics.  Diogenes claims that Stoicism is part of a philosophical succession going back to Cynicism and prior to that Antisthenes, who was a friend and student of Socrates.  So the “Cynic-Stoic succession” is thereby traced all the way back to its supposed origin in the teachings of Socrates.  Modern scholars believe it’s unlikely Diogenes of Sinope, the first Cynic, actually met Antisthenes.  Nevertheless, it’s quite possible he was inspired by his writings, so there may be a grain of truth in the notion that Antisthenes was somehow the forerunner of the Cynic, and thereby the Stoic, tradition.  In any case, Zeno of Citium, the founder of Stoicism, was undoubtedly greatly influenced by Cynicism, and we’re told he studied under the Cynic Crates of Thebes for many years before founding the Stoa.

Book Seven of the Lives therefore deals with the Stoic philosophers, starting with Zeno.  The first chapter, which covers Zeno’s life, contains a lengthy outline of early Stoicism in general.  Book Seven also contains chapters on several other important philosophers of the early Stoic school, such as Cleanthes, the successor of Zeno, and it concludes with a lengthy chapter on Chrysippus, the third head of the school.  However, curiously, the chapter on Zeno and the early doctrines of the school is immediately followed by three chapters on lesser-known Stoics, described by Diogenes Laertius as “heterodox”, i.e., unorthodox, or renegades from the school.

[Among the pupils of Zeno were:] Ariston, the son of Miltiades and a native of Chios, who introduced the doctrine of things morally indifferent; Herillus of Carthage, who affirmed knowledge to be the end; Dionysius, who became a renegade to the doctrine of pleasure, for owing to the severity of his ophthalmia he had no longer the nerve to call pain a thing indifferent: his native place was Heraclea. (Diogenes Laertius, 7.1)

It may be noteworthy that although all three are described as pupils of Zeno, only Dionysius is actually labelled a renegade from the school, and he is the only one of whom we are specifically told that he joined another school, the Cyrenaics.  Before introducing these three, at the end of the chapter on Zeno, he also writes as follows referring to them as “Stoics”:

But the points on which certain of the Stoics differed from the rest are the following. (Diogenes Laertius, 7.1)

Diogenes concludes the three chapters on heterodox Stoics by saying:

These three, then, are the heterodox Stoics.  The legitimate successor to Zeno, however, was Cleanthes: of whom we have now to speak. (Lives, 7.4)

This can be taken as evidence that there were important internal disputes that helped to shape the early development of the Stoic school.  It’s not entirely clear to what extent these three philosophers were subsequently associated with the Stoics, except that we’re told Dionysius left to join the Cyrenaics.  Each was called heterodox because of doctrinal disagreements with Zeno, which happened to be quite different in each case.  Their reasons for being classed as “heterodox” or “renegade” Stoics are worth outlining as they provide an interesting overview of three distinct ways in which an early Stoic could be considered to have strayed so far from Zeno’s teachings that he was no longer considered a Stoic at all.  In other words, this gives us some insight into which beliefs were considered orthodox to early Stoicism.

1. Aristo of Chios

Also spelled “Ariston” and known as “Aristo the Bald”.  Although he came to disagree with Zeno’s teachings, Aristo seems to have been an important and influential teacher in his own right.  We’re told elsewhere that Marcus Aurelius was inspired to become a philosopher, many centuries later, by reading Aristo’s works.

Aristo rejected the value of studying Physics and Logic, and instead claimed that philosophers should only concern themselves with Ethics.  This attitude appears to resemble that of the Cynics.  Zeno started his own philosophical career as a Cynic but began to study at the Academy and the Megarian school, apparently because he felt that some understanding of Logic and Physics was important, and lacking from the Cynic philosophy.  Stoicism was therefore known for its threefold curriculum: Ethics, Physics and Logic.  However, different Stoics appear to have placed different degrees of importance on these three disciplines.  It’s often felt that the late Roman Stoics are primarily concerned with Ethics, and have noticeably less to say about Physics and Logic, although this may be partly a reflection of the fact that only a small fragment of their writings survive.  It sometimes appears that Logic and Physics are important to Stoicism, but perhaps not absolutely essential.  For instance, their heroes, such as Heracles and Diogenes, did not excel in Physics or Logic, and yet were considered role-models because of their moral character.  Aristo appears to have gone too far, though, by completely rejecting the value of Logic and Physics for philosophy.

Aristo also rejected Zeno’s concept of “preferred” indifferents and insisted that apart from virtue and vice, everything else must be regarded as totally indifferent.  In this respect, he also appears more aligned with the Cynics rather than the Stoics.  Although, curiously, he doesn’t appear to be considered particularly aligned with Cynicism by other ancient authors.  Again, some scholars see the introduction of the concept of “preferred” indifferents as one of the key things that distinguished Stoics from Cynics.

2. Herillus of Carthage

Also spelled “Erillus” and sometimes said to be of Chalcedon rather than Carthage, presumably due to an error in the ancient sources.

He argued that knowledge (episteme) should be regarded as the true goal of life, rather than virtue, and he appears to have said also that such knowledge takes different forms in different circumstances.  The early Stoics appear to have argued that virtue itself is a form of knowledge.  The highest virtue, wisdom, is described as the knowledge of good and evil, and of indifferent things, and the other virtues are defined in similar times as ethical knowledge in relation to different forms of action.  This suggests that Herillus broke from the teachings of Zeno by making knowledge in general the goal of life, whereas the Stoics considered only ethical knowledge, or moral wisdom, to be an end in itself.  They probably considered other forms of knowledge, or science, to be of some kind of subordinate value.  For example, Chrysippus reputedly taught that Physics is of value only insofar as it contributes to our understanding of Ethics.  Stoic literature is full of warnings against those who pursue abstract learning for its own sake, without grounding it somehow in the practicalities of living a virtuous life.  Diogenes Laertius has relatively little to say about him, but he writes:

Herillus of Carthage declared the end of action to be Knowledge, that is, so to live always as to make the scientific life the standard in all things and not to be misled by ignorance. Knowledge he defined as a habit of mind, not to be upset by argument, in the acceptance of presentations. Sometimes he used to say there was no single end of action, but it shifted according to varying circumstances and objects, as the same bronze might become a statue either of Alexander or of Socrates. He made a distinction between end-in-chief and subordinate end: even the unwise may aim at the latter, but only the wise seek the true end of life. Everything that lies between virtue and vice he pronounced indifferent. His writings, though they do not occupy much space, are full of vigour and contain some controversial passages in reply to Zeno.

We’re told he wrote several books on topics including, training exercises (askesis), the passions, on judgements or opinions (hupolepsis), and on Hermes, and Medea.  Diogenes Laertius tells us in his chapter on the life of Cleanthes, the successor of Zeno as head of the Stoa, that he wrote a book entitled “Reply to Herillus”.  This suggests that Herillus’ break from the Stoa and his criticisms of Zeno were significant enough for the second head of the school to attempt to refute them in writing.

It’s perhaps tempting to see Herillus as leaning away from the Stoa and more in the direction of Plato’s Academy, and perhaps the Aristotelians, in this respect.

3. Dionysius of Heraclea

Dionysius of Heraclea (c. 330 – c. 250 BC) was also known as “Dionysius the Renegade”, because of his radical break from the Stoic teachings of Zeno.  The Greek word literally means one who changes sides or changes his mind, i.e., a turn-coat or renegade.  It’s perhaps notable that neither Aristo nor Herillus are labelled as ones who changed sides, or renegades from the Stoic school.  Perhaps this is meant to imply that they remained Stoics, albeit unorthodox ones, whereas Dionysius actually left the Stoa.

He had previously studied philosophy in the Megarian school, before becoming a student of Zeno.  Dionysius left the Stoa because he came to value pleasure (hedone), and the absence of pain, as the goal of life, rather than virtue.  We’re actually told that Dionysius left the Stoa to join the Cyrenaic school, who made pleasure the goal of life.  We’re told Dionysius was driven to this conclusion by the intolerable pain and discomfort of an eye-infection.  In his chapter on the life of Zeno, Diogenes Laertius writes:

When Dionysius the Renegade asked [Zeno], “Why am I the only pupil you do not correct?” the reply was, “Because I mistrust you.”

We know little more about Dionysius. He wrote two books on freedom from passions (apatheia), two on training exercises (askesis), four on pleasure (hedone), among others.

Zeno classed pleasure and pain as key examples of morally “indifferent” things.  So Dionysius’ claim that pleasure is the goal of life would have constituted a very radical departure from “orthodox” Stoic teachings, so much so that he inevitably left and rebranded himself as a Cyrenaic.

The Cyrenaic school was quite different from the Epicurean school, which rose to prominence slightly later.  However, this schism in the early Stoa can probably be seen as prefiguring the subsequent and long-running disagreements between the Stoics and Epicureans.