Zeno (Stoic): 'Live According to Nature' — The Philosopher Who Accepted Fate and Held Virtue Alone to Be Good

Key Takeaways

• "Live according to nature" (homologoumenōs tē physei zēn): Zeno taught that living in harmony with the reason (logos) that pervades the cosmos is the path to human happiness. This does not mean "follow your instincts"; it means fully realising our nature as rational beings.
• Virtue alone is good: Health and wealth are "preferable" but not good. The only true good is virtue (aretē), and with virtue one can be happy even in slavery. This radical claim opened the door to a universal ethics transcending social rank.
• Overcoming the passions (apatheia): Passions (pathē) such as anger and fear arise from false judgements. Correct the judgement and the passion disappears — an insight that connects directly to modern cognitive behavioural therapy.

Life and Historical Context

Zeno was born around 334 BCE in Citium (modern-day Larnaca) on the island of Cyprus. Citium was a Phoenician colony situated at the crossroads of Greek and Eastern cultures. His father Mnaseas was a merchant, and Zeno initially engaged in trade himself. Growing up immersed in different languages and customs from an early age, this multicultural background is thought to have provided the foundation for his later vision of "world citizenship" — a concept that transcended city-state and ethnic boundaries.

Zeno lived through a period of profound upheaval in the Greek world. Alexander the Great's eastern campaigns (334–323 BCE) had spread Greek culture eastward, but after Alexander's death the empire was torn apart by the Wars of the Successors (the Diadochoi Wars), and the autonomy of the polis — the city-state — was effectively lost. Citizens became subjects of vast kingdoms and lost their political agency. To draw a modern analogy, it was as if the frameworks of the nation-state had collapsed and individuals felt powerless before enormous forces beyond their control. In this turbulent age, the question "How can an individual live well?" became urgently pressing. The Epicurean school, the Sceptics, and the Stoics — the three great Hellenistic schools — all arose in response to this question.

Zeno came to Athens around the age of twenty-two, and first studied under Crates, a Cynic (Kynikos). The Cynics radically rejected social conventions and practised a life stripped down to the natural minimum. Their forerunner Diogenes was said to have lived in a barrel, eaten in public, and shown complete indifference to social decorum. The idea of "a life unshackled by convention" became a foundational layer of Zeno's thought, but he eventually found its limitations — all spectacle and no systematic theory. Intuition alone is not enough; philosophy needs logical grounding. Thinking thus, Zeno went on to study logic and dialectic under Stilpo and Diodorus Cronus of the Megarian school, and also attended Plato's Academy. Synthesising these diverse influences, he founded his own school around 300 BCE. Because his lectures were held at the Painted Porch (Stoa Poikilē), the school came to be called "Stoic."

Zeno led an austere life and earned the deep respect of the Athenian citizenry. Diogenes Laërtius records in his Lives of the Eminent Philosophers that the city of Athens voted to award Zeno a golden crown and a public burial in the Kerameikos cemetery (VII.10–12). The decree praised him for having "shown the young a life of virtue and temperance" — the highest public honour bestowed on a philosopher. Around 263 BCE, Zeno is said to have taken his own life. In Stoic philosophy, a rationally judged departure — when old age or severe illness made a life of reason no longer possible — was considered permissible.

Mini-Timeline

• c. 334 BCE: Born at Citium, Cyprus
• 323 BCE: Alexander the Great dies. The Wars of the Successors begin
• c. 312 BCE: After his shipwreck, arrives in Athens. Studies under the Cynic Crates
• c. 310–301 BCE: Also studies under Stilpo of the Megarian school and Polemo of the Academy
• c. 300 BCE: Begins lecturing at the Painted Porch. Founding of the Stoic school
• c. 300–280s BCE: Writes his major work Republic (Politeia) and numerous other treatises
• c. 263 BCE: Dies in Athens (aged about 71). His successor is Cleanthes

What Did This Philosopher Ask?

When the age of the polis came to an end and citizens were no longer masters of their own political community, philosophy confronted a new question. Plato and Aristotle had located the good life within the good polis — political participation was the fulfilment of citizenship, and happiness could not exist outside the community. But in the Hellenistic world, where the polis was no longer a self-sufficient unit, the individual had to find the foundation of happiness within.

Zeno's fundamental question was this: Is happiness independent of external circumstances possible? If so, in what kind of life is it realised? This question has lost none of its urgency for us today — when we suddenly lose a job, fall ill, or lose someone we love.

Zeno's answer was clear. Happiness lies in virtue. Virtue is a way of life in harmony with the rational law of the cosmos (logos), and it depends on neither wealth nor power nor health. In other words, the power to judge rightly and act rightly — this is something no one can take from us. This is the heart of Stoic ethics. The life of Zeno himself — who lost his entire fortune in a storm and from that loss discovered the path of philosophy — was a living proof of this proposition.

Core Theories

1. The Tripartition of Philosophy — Logic, Physics, Ethics

Zeno divided philosophy into three branches: logic (logikē), physics (physikē), and ethics (ēthikē). This division later became the standard curriculum for philosophical education. Logic is "the method of thinking correctly"; physics is "understanding how the world is constituted"; ethics is "the guide to how one should live."

The Stoics explained the relationship between these three branches with skilful analogies. In the analogy of the egg, the shell is logic (the framework that guards thought from error), the white is physics (the nourishment of understanding the world), and the yolk is ethics (the purpose and core of everything). In the analogy of the field, the fence is logic (protecting thought from external attack), the soil is physics (the ground in which knowledge grows), and the ripening fruit is ethics (the ultimate harvest) (Diogenes Laërtius VII.40). What both analogies share is the conviction that ethics is the ultimate purpose of philosophy. But to practise ethics properly, one needs an understanding of how the world works (physics) and the methods of correct reasoning (logic). Philosophy is not a game of intellect; it is an integrated endeavour for living well.

2. Physics — A Cosmos Pervaded by Logos

Stoic physics is materialist. Only bodies exist; non-material realities such as Plato's Forms — "perfect shapes existing in an invisible other world" — are not admitted. But this is no simple materialism. The cosmos is pervaded by a divine reason — logos — and everything is part of this logos. The cosmos itself, as it were, is a vast intelligence, and stones, trees, animals, and human beings are all incorporated as parts of it. The Stoics also called this logos "creative fire" (pyr technikon) and "pneuma" (breath). They were inheriting Heraclitus' concepts of universal flux and logos.

This worldview carries several important consequences. First, the cosmos is a rational order, and there is no chance. Everything lies within a chain of causation and is determined as fate (heimarmenē). Second, since human reason is part of the cosmic logos, to live according to reason is to live according to nature. Third, all things are connected to one another through the logos — the Stoics called this "sympathy" (sympatheia). The cosmos is not a random collection of parts but a whole that functions in concert, like a single organism.

The Stoics further taught that the cosmos periodically perishes in a great conflagration (ekpyrōsis) and is then regenerated from the logos as the same cosmos all over again — an eternal recurrence in which everything repeats without the slightest variation. This grand cosmology is an expression of their trust in the cosmos's perfect rationality. Nothing in the cosmos is wasted, and everything has meaning — and precisely for this reason, the Stoics held, there is a rationale in accepting what happens.

3. Ethics — Virtue Alone Is Good

The foundation of Stoic ethics is the proposition that "virtue (aretē) alone is good, and vice (kakia) alone is evil." Health, wealth, and honour are "preferred things" (proēgmena) but are themselves neither good nor evil — they are "indifferents" (adiaphora).

What does this mean in practice? Even if you lose your fortune in a storm — as Zeno himself did — the ability to judge rightly and act rightly cannot be taken from you. Health can be lost to illness or old age, but virtue can only be surrendered by one's own will. Conversely, someone who amasses great wealth by dishonest means may appear successful, but for the Stoics such a person is unhappy — because they lack virtue. Happiness resides in a life lived in accordance with virtue, not in external goods. This does not mean the Stoics told people to disregard health and wealth entirely. These are "things worth choosing," but one must never sacrifice virtue to obtain them. It is natural to wish to be healthy. But one can be happy even without health — that was the Stoics' revolutionary claim.

Virtue was systematised into four cardinal virtues: wisdom (phronēsis — the ability to discern what is good and what is evil), courage (andreia — the strength to face difficulty), temperance (sōphrosynē — the ability to control desire), and justice (dikaiosynē — the disposition to treat others fairly). Moreover, the Stoics held these virtues to be inseparable. Whoever possesses one possesses all; whoever lacks one lacks all. This "unity of the virtues" was a thesis that provoked much subsequent debate. A soldier, for example, who fights bravely in battle but engages in unjust plunder is not truly brave in the Stoic view — courage without justice is mere recklessness.

4. Oikeiōsis — From Self-Affinity to Concern for Others

Another pillar of Stoic ethics is "oikeiōsis" (self-affinity, appropriation). Every living creature from birth possesses an impulse toward self-preservation, seeking what is suited to it and avoiding what is harmful. An infant reaches for its mother's milk and withdraws its hand from something hot — this is oikeiōsis at work. Animals remain at this level, but in human beings reason develops with maturity, and eventually "living according to reason" itself comes to be recognised as the highest end. One eats not because one wants to, but because it is rational to do so — human maturation, for the Stoics, is a transition from impulse to reason.

Oikeiōsis further expands from the self to others. We feel affection first for parents and children, then for friends and fellow citizens, and ultimately for all rational beings — the circle of concern widens outward. The later Stoic philosopher Hierocles explained this with the model of "concentric circles": the self at the centre, surrounded by family, community, nation, and finally all of humanity. It is natural for us to react more strongly to the suffering of our own family than to that of people in a distant land. But the sage contracts these circles as far as possible, extending to distant others the same care he shows to those closest to him. This theory is the ethical foundation of Stoic cosmopolitanism.

5. The Theory of the Passions (pathē) — Emotions Are Judgements

For the Stoics, passions such as anger, fear, grief, and indulgence in pleasure are not irresistible forces that assail us from outside. They arise from false judgements — for example, the judgement that "losing wealth is a terrible evil." When you feel anger in a traffic jam, it is because you are unconsciously judging that "being late is a great evil." If you revise that judgement to "being late is inconvenient but neither good nor evil," the anger does not arise. The Stoics classified the passions into four kinds: excessive desire for a future good (epithymia), fear of a future evil (phobos), excessive pleasure in a present good (hēdonē), and distress at a present evil (lypē). All are founded on the judgement that "what is neither good nor evil is good or evil."

This theory was groundbreaking. If emotions originate in judgements, then changing the judgement changes the emotion. The Stoic goal of "apatheia" (freedom from passion) does not mean becoming a cold, unfeeling person. It means correcting, through reason, passions founded on false judgements. Emotions do not vanish — what remains are healthy emotions (eupatheiai): joy (chara), caution (eulabeia), and rational wish (boulēsis). These are not passions but sound movements of the mind based on correct judgement. The Stoic ideal is not "a person who feels nothing" but "a person who feels rightly."

This insight directly influenced Albert Ellis (founder of Rational Emotive Behaviour Therapy) and Aaron Beck (founder of cognitive therapy) two thousand years later. Ellis publicly acknowledged the Stoic influence, and placed at the foundation of his therapy the proposition of Epictetus: "What disturbs people is not things, but their judgements about things."

6. Fate and Freedom — Autonomy Within Determinism

The Stoics accepted the causal determinism of the cosmos. Every event is the necessary result of a preceding cause. Where, then, is human freedom — if everything is determined, is there any point in effort or choice?

Zeno's successor Chrysippus gave a skilful answer. Push a cylinder from the top of a slope and it rolls. Without the push (the external cause) it would not roll, but the way it rolls is determined by its cylindrical shape (its internal nature). A cube would not roll. In the same way, external circumstances compel us to choose, but how we respond depends on our internal character — our reason and virtue. When confronted with sudden redundancy, one person despairs while another discovers a new path — this difference in response to the same event is where freedom resides. Chrysippus formalised this as the distinction between "antecedent causes" (external stimuli) and "principal causes" (the agent's own nature). Moral responsibility attaches to the principal cause.

The later Stoic Epictetus crystallised this thought still more sharply: "Distinguish between what is within our power (eph' hēmin) and what is not" (Encheiridion 1.1). Our judgements, will, and desires are within our power. The body's health, other people's actions, and the weather are not. So long as we do not cling to what lies outside our power, our inner freedom is preserved. The Stoics also expressed this attitude toward fate with the analogy of a dog tied to a cart. If the dog runs along willingly it proceeds with ease; if it resists it is dragged. Either way the direction is the same — so it is wiser to go willingly. Not to resist the unavoidable, but to choose one's attitude toward it — this is the essence of Stoic freedom.

7. The Sage (sophos) — An Ideal

The Stoics called the person who perfectly embodies virtue "the sage" (sophos). The sage judges correctly in every situation, is untroubled by passion, and lives in harmony with fate. Even amid fire the sage is happy; even under torture the sage is undisturbed.

Yet the Stoics acknowledged that such a sage is exceedingly rare. It was even debated whether any figure in history besides Socrates or Heracles could properly be called a sage. Does this make the ideal of the sage unrealistic? The Stoics did not think so. The sage is a goal to be aimed at, not a description of ordinary life. The great majority of human beings are "those making progress" (prokoptontes) — people who move closer to virtue through daily practice. Like the North Star: you cannot reach it, but it serves as a guide for travelling in the right direction. How to live with the tension between the perfect ideal and imperfect reality — that is the crux of Stoic practice.

8. Logic — A Forerunner of Propositional Logic

Stoic logic differs from Aristotle's syllogistic (the logic of terms) in that it deals with the connective relations between propositions — propositional logic. To put it simply, whereas Aristotle's logic analyses subject–predicate relations such as "All A are B," the Stoics focused on the relations between sentences: "If p then q," "p or q," "p and q." The approach has an affinity with the "if-then" constructs of modern programming.

The "five indemonstrables" (anapodeiktoi) systematised by Chrysippus correspond to inference rules in modern logic — modus ponens, modus tollens, and so on. For example: "If it is day, it is light. It is day. Therefore it is light" — this corresponds to the first indemonstrable. This achievement was largely forgotten after the Middle Ages, when Aristotle's syllogistic was thought to be the only logical system. It was not until the nineteenth century, when Frege and others constructed symbolic logic, that Stoic propositional logic was reassessed as a pioneering achievement.

The Stoics further proposed, in epistemology, the "apprehensive impression" (katalēptikē phantasia) as the criterion for certain knowledge. Among the impressions received from the external world, some accurately represent the reality of their objects; reason gives its "assent" (synkatathesis) to these, and knowledge is thereby established. This is closely tied to ethics — for if one cannot perceive reality correctly, correct judgement is impossible. The Sceptics attacked the validity of this "assent" vigorously, but for the Stoics the certainty of cognition was a prerequisite for ethical action and a line they would not surrender.

9. Cosmopolitanism

Zeno's major work, the Republic (Politeia), survives only in fragments, but it set out a vision in which all rational beings belong to a single community, transcending race and city-state. A society without coinage, temples, or courts, in which virtue alone is the criterion of citizenship — this radical vision, which inherited the Cynic spirit, provoked controversy even among later Stoics.

So long as they share in the logos, slaves and kings, Greeks and barbarians (barbaroi) are equal — this idea was extraordinarily radical in the ancient world. At a time when Greeks looked down on other peoples as "barbarians," the Stoics declared that all who possess reason are equal. When the Roman Empire needed a universal law (ius gentium) to govern its many peoples, Stoic cosmopolitanism provided the intellectual foundations for legal thought. The distant headwaters of modern natural-law theory and the concept of human rights can be traced back to this source.

Guide to Key Texts

• All of Zeno's own writings have been lost; none survives in complete form. The following are collections of fragments and testimonies, together with important Stoic texts.
• Stoicorum Veterum Fragmenta (SVF), ed. H. von Arnim, 4 vols., 1903–1924 — The standard comprehensive collection of fragments and testimonies of the early Stoics. Volume 1 is devoted to Zeno.
• Diogenes Laërtius, Lives of the Eminent Philosophers, Book VII — The most detailed ancient source on Zeno's life and Stoic doctrine. Translation: R.D. Hicks (Loeb Classical Library, 1925); more recent: Pamela Mensch (Oxford UP, 2018).
• Epictetus, Encheiridion (Handbook) — The practical essence of Stoic ethics. Short, accessible, and the ideal introduction. Translation: W.A. Oldfather (Loeb Classical Library, 1928); or Robert Dobbin (Penguin, 2008).
• Marcus Aurelius, Meditations — Stoic reflections written by the Roman emperor in his campaign tent. A living record of Stoic philosophy in practice. Translation: Robin Hard (Oxford UP, 2011).
• Seneca, On the Shortness of Life — A celebrated essay questioning the use of time and the art of living. An ideal introduction to Stoic thinking about time. Translation: C.D.N. Costa (Penguin, 2004).

Major Criticisms and Controversies

1. The Epicureans — Is pleasure not the good? The Epicureans, contemporaries of the Stoics, maintained that the good is pleasure (hēdonē) — above all, the absence of pain (ataraxia). The Stoic position that virtue alone is good ignores natural human desires, the Epicureans charged. The Stoics, however, did not reject pleasure outright — their view was that pleasure is merely a by-product that accompanies natural activity and must not be made into an end. "Is the source of happiness pleasure or virtue?" — this debate was one of the central oppositions of ancient philosophy and continues to this day.

2. The Sceptics — Is certain knowledge possible? The Academic Sceptics (Arcesilaus, Carneades) attacked Stoic epistemology — the claim that certain knowledge can be obtained through apprehensive impressions — with unrelenting force. Dreams and illusions are indistinguishable from impressions produced by real objects. Without certain knowledge, the foundation for virtuous action collapses. This epistemological debate forced the Stoics to refine their doctrine and ultimately spurred the development of Stoic epistemology.

3. Determinism and moral responsibility: If everything is determined by fate, then moral praise and blame would seem to be meaningless. Could one not say that even a criminal was merely following fate? This objection was raised repeatedly from antiquity. Chrysippus responded with the distinction between antecedent and principal causes described above, but the compatibility of determinism and free will remains one of philosophy's perennial puzzles.

4. Criticism of "indifferents": The Stoic claim that even health and life are not "good" but merely "preferred" strikes many as counter-intuitive. Could one really say to a seriously ill person, "Health is not a good"? The Peripatetics (Aristotle's school) argued that external goods — health, friends, a certain level of wealth — are also necessary for happiness, and criticised Stoic rigorism. In practice, the later Stoics (Panaetius, Posidonius) softened this position and moved closer to the Peripatetic view.

Influence and Legacy

Antecedents: Socrates' proposition that "virtue is knowledge" stands at the starting point of Stoic ethics. The Cynics' asceticism and critique of convention, Heraclitus' concept of logos and his cosmology of fire, and Megarian logic all formed the foundations of Stoicism. Plato's vision of an ideal state also exerted a dialogic influence on Zeno's Republic.

Development of the school: After Zeno, Cleanthes (the second head of the school) deepened Stoic theology, and Chrysippus (the third head) refined logic and ethics. "Without Chrysippus there would be no Stoa," it was said. Zeno built the skeleton; Chrysippus supplied the muscle and sinew.

Roman Stoicism: Seneca, Epictetus, and Marcus Aurelius developed Stoic philosophy in practical and literary directions and remain the most widely read Stoic authors today. A slave (Epictetus) and an emperor (Marcus Aurelius) lived by the same philosophy — that fact alone is testimony to Stoic universalism.

Relation to Christianity: Early Christianity absorbed Stoic natural-law theory, the concept of logos, and ascetic ethics on a large scale. The opening of the Gospel of John — "In the beginning was the Logos" — has been noted by scholars for its resonance with the Stoic logos concept. Stoic expressions can also be found scattered through the letters of the Apostle Paul.

Modern ethics: Kant's deontology — unconditional obedience to the moral law, the sharp separation of happiness and morality — shows a strong Stoic influence. Kant's injunction to "do your duty regardless of the consequences" lies on the same trajectory as the Stoic insight that "consequences lie outside our power, but the rightness of our actions lies within it." Spinoza's "mastery of the affects" is likewise a Stoic theme, and Descartes' Passions of the Soul was written with Stoicism in mind.

Connections to the Present

First, cognitive behavioural therapy (CBT). "What disturbs people is not events, but their judgements about events" — this proposition of Epictetus is the basic principle of CBT itself. Consider: it is not the event "my boss reprimanded me" that causes suffering, but the judgement "being reprimanded by my boss means I am incompetent." If this judgement is revised to "my boss merely pointed out areas for improvement," the suffering is reduced. The CBT method of correcting cognitive distortions that give rise to anxiety and anger is, in essence, a modern version of the Stoic theory of the passions.

Second, the "modern Stoicism" movement. "Stoic Week," held every October, has become a global event. In an age of uncertainty, the Stoic principle of "focusing on what you can control" resonates powerfully in times of pandemic and economic anxiety. Ryan Holiday's books have brought Stoic philosophy to a general readership and become worldwide bestsellers.

Third, resilience and leadership. In the fields of military education, management studies, and sports psychology, the Stoic concept of resilience is being actively applied. Former US Navy Vice Admiral James Stockdale endured seven and a half years as a prisoner of war in Vietnam through the philosophy of Epictetus. The distinction between "what is within our power" and "what is not" proved to be a principle capable of preserving human dignity even in the most extreme circumstances.

Fourth, environmental ethics and cosmic solidarity. The Stoic concept of "sympathy" (sympatheia) — the cosmos as an organism in which all things are interconnected through the logos — has a natural affinity with the contemporary environmental-ethical perspective of "viewing the entire Earth as a single system." Human beings are not masters of nature but part of it — this Stoic insight takes on renewed significance in an age of climate change.

Questions for the Reader

• Of the anxieties and angers you experience in daily life, how many could genuinely be dissolved by "changing the judgement"? Can the Stoic theory of the passions serve as a practical prescription for mental suffering?
• Is the Stoic claim that "virtue alone is good" too severe? Does classifying health and the presence of loved ones as "not good but merely preferred" contradict our lived experience?
• Is the Stoic compatibilism — the view that freedom exists even though everything is fated — persuasive? Or is it merely self-deception?

References

• (Fragments): von Arnim, Hans. Stoicorum Veterum Fragmenta (SVF). 4 vols. Leipzig: Teubner, 1903–1924.
• (Fragments & translation): Long, A.A. & Sedley, D.N. The Hellenistic Philosophers. 2 vols. Cambridge: Cambridge University Press, 1987.
• (Ancient testimony): Diogenes Laërtius. Lives of the Eminent Philosophers, Book VII. Trans. Pamela Mensch. Oxford UP, 2018.
• (Overview): Sellars, John. Stoicism. London: Routledge, 2006.
• (Overview): Inwood, Brad (ed.). The Cambridge Companion to the Stoics. Cambridge: Cambridge University Press, 2003.
• (Modern application): Robertson, Donald. How to Think Like a Roman Emperor. New York: St. Martin's Press, 2019.
• (Web): Stanford Encyclopedia of Philosophy, "Stoicism" (Marion Durand, Simon Shogry & Dirk Baltzly, first published 2023). https://plato.stanford.edu/entries/stoicism/