☀️ Module 6 — Virtue as the Strength of the Soul | Cleanthes Course
Updated: Sep 5
Free Course by Everything IFS Academy | Stoicism Series
Help us reach the people who may need this most by sharing this free course with friends, family, colleagues, online communities, social media or on your own website.
🎧 Audio is read by AI
Module 6 — Virtue as the Strength of the Soul
Two people get the same devastating news. One of them comes apart, swallowed by it, unable to function for weeks. The other absorbs the blow, grieves it honestly, and somehow stays standing, still able to show up for the people who need them. The usual explanation is that the second person is simply stronger, born with some toughness the first one lacks. Cleanthes thought that was almost right, but incomplete. He agreed that it came down to strength. He disagreed that strength was a fixed gift of temperament. In his view, the strength that lets a soul hold under a weight that crushes others is a real, physical condition of that soul, and like any condition, it can be built. To see how, his ethics reaches straight back into his physics.
Virtue as the Tension of the Soul
Cleanthes is known above all for one idea, the doctrine of tonos, or tension, which has its own full lesson in this course. The short version is this: everything that exists is pneuma, a fine fiery breath, held together by an active inner tension, and a thing is what it is depending on how tightly that breath is strung. The soul is no exception. A human soul, for Cleanthes, is pneuma at the highest tension nature reaches, which means a soul can run more taut or more slack, the way a string can.
Here is the move that makes Cleanthes' ethics his own. If the soul is a tensed thing, then a strong soul simply is a well-tensed one, and a weak soul is a slack one. And virtue, the excellence of a human being, turns out to be nothing more mysterious than the soul held at proper tension, strung tight and true. Vice is the soul gone slack. This is a striking unification. In most accounts of ethics, strength of character is a metaphor loosely borrowed from the body. In Cleanthes' account it is not a metaphor at all. The strength of a soul and the strength of a muscle are the same kind of thing, tension in pneuma, differing only in degree. Character is, quite literally, a matter of how tightly a person is strung.
The Passions as Weakness
This gives Cleanthes a sharp and physical account of what goes wrong in a person, and it centers on what the Stoics called the passions. The word needs care, because it does not mean today what it meant to them. In Stoic usage, the passions, in Greek the pathē, are not emotions in general and not feeling as such. They are a specific category: the strong, disturbing, irrational impulses that seize a person and pull them off course, things like raging anger, gnawing fear, devouring grief, and consuming craving. A passion, in this technical sense, is an upheaval that overrides reason and runs a person around.
For Cleanthes, the passions are exactly what his physics would predict. They are the soul losing tension. When fear floods in, or grief, or appetite, what has happened is that the soul has gone slack at the crucial moment and been yanked off its feet by an impulse it could not hold against. The passions are not strength of feeling. They are weakness, failures of the soul's tension, the slack string sounding its sour note. The fuller Stoic account of why the passions arise in the first place, that they are rooted in mistaken judgments about what is good and bad, is the teaching of Epictetus and has its own lesson in his course. Cleanthes' distinctive contribution is the physical diagnosis: a person ruled by passion is a person whose soul has lost its proper tension.
This is also the place to clear away the single most common misunderstanding of Stoicism. The popular image holds that a Stoic is someone who feels nothing, a person of stone, suppressing every emotion behind a blank face. That is not the teaching, and it never was. The goal is not numbness. A slack, dead soul that feels nothing would be the exact opposite of the taut, alive soul Cleanthes is describing. What the Stoic aims at is not the absence of feeling but the presence of strength: a soul so well-strung that it is not jerked off its feet by every fear and craving that arrives. Such a soul still feels. It is simply not at the mercy of what it feels.
Courage and Self-Control
If virtue is the soul at proper tension, then the particular virtues are that tension brought to bear in particular situations. Cleanthes worked this out most clearly for two of them, defining each as the soul's strength applied to a specific kind of pressure.
Courage is tension under what must be endured. Courage, for Cleanthes, is the soul holding its tension in the face of things that have to be borne: pain, danger, loss, fear. The frightened person is the one whose soul goes slack when the threat appears and gives way. The courageous person is not someone who feels no fear, but someone whose soul stays strung taut enough to act rightly while afraid. Picture a man who has to deliver hard news he knows will wound someone he loves, and who is tempted to flinch, to soften it into a half-lie, to put it off another day. Courage is the tension that lets him stay in the room and say the true thing anyway.
Self-control is tension under what must be resisted. Self-control, what the Greeks called temperance, is the same strength applied to the opposite pull, not the pressure to flee but the lure to indulge. It is the soul holding firm against the appetite or temptation that would drag it off the course it knows is right. Picture a woman who has committed to something difficult and good, and who feels the steady tug of the easier, more pleasant path away from it. Self-control is the tension that keeps her on the road she chose precisely when the pull to leave it is strongest.
Both are the same underlying thing, the soul's tension, simply meeting two different forces: the things that push a person to give way, and the things that lure a person to give in.
Pleasure as Contrary to Nature
Cleanthes pushed one of these lines further than most Stoics were willing to go, and it is worth seeing both his version and the pushback, because the disagreement is illuminating. The question was what to make of pleasure. The mainstream Stoic position treated pleasure as an indifferent, something neither good nor bad in itself, which a wise person might reasonably take or leave depending on the situation. Cleanthes went harder. He held that pleasure is not merely neutral but worthless, and worse than worthless. He called it contrary to nature, a thing of no value that pulls the soul away from its proper work.
The steelman of his position runs like this. If virtue is the soul held at full tension, then pleasure, the soft, relaxing, gratifying sensation, is precisely the experience that invites the soul to let go, to loosen, to slacken. Pleasure feels good exactly because it is the soul releasing tension, and for Cleanthes that release is the first motion of weakness. A life organized around the pursuit of pleasant feeling is therefore a life organized around going slack, around the slow erosion of the one thing that makes a person strong. On those terms, calling pleasure contrary to nature is not prudishness. It is the consistent conclusion of his whole physics of the soul.
It is also a minority view, and honesty requires saying so. Many Stoics found Cleanthes too severe here. The more standard line kept pleasure among the indifferents, or treated the pleasure that naturally accompanies good activity as a harmless byproduct rather than an enemy to be fought. The school never finally settled on Cleanthes' hardest version. But the position is instructive precisely because it is extreme. It shows how seriously he took his own central idea, and how far he was willing to follow it once he had it in hand.
The Long Road to Virtue
There is nothing easy or cheerful in Cleanthes' picture of how a person actually becomes strong, and he refused to pretend otherwise. He observed, in a line that has survived him, that people walk in wickedness all their lives, or at least for the greater part of them, and that if they ever reach virtue at all, it comes late, at the very sunset of their days.
It would be easy to read that as despair, but it is not. It is sober realism, the same unflinching honesty Cleanthes brought to everything. He is not saying that virtue is impossible or that the effort is wasted. He is saying that a soul is not re-strung in a weekend, that the work of bringing a slack soul up to proper tension is the work of a lifetime, and that most people are still at it when they die, if they ever began. There is something steadying rather than crushing in the claim, once it is taken plainly. It removes the false expectation of quick transformation, and with it the despair that arrives when the quick transformation does not. The task is long because the thing being built is real. A person is not behind schedule. There is no schedule. There is only the slow tightening, day after day, of the one string that matters.
One Event, Two Tensions
Set the whole teaching down into a single ordinary moment. Sam is blamed, publicly and largely unfairly, for the failure of a project, in a room full of people whose respect matters to him. Run that same hour through two souls at two tensions.
The slack soul comes apart. The shame and the anger arrive, and there is nothing strung tight enough to hold against them, so they take the controls. Perhaps he lashes back and makes an enemy he did not need; perhaps he shuts down and fails to say the one true thing he should have said. Either way, the hour owns him. And it keeps owning him, replayed for weeks afterward, leaking into his confidence, his sleep, and his patience with people who had nothing to do with it. The event happened once. The slack soul suffers it a hundred times.
The taut soul meets the very same hour. The sting is just as sharp, because a well-strung soul is not a numb one, and the unfairness of it lands fully. But the tension holds. The anger is felt without seizing the controls. The shame is felt without hardening into a verdict on his worth. And because the soul is not busy being dragged behind its own reaction, something is left over for the response the moment actually calls for: the steady correction of what was false, the calm ownership of what was genuinely his, the refusal to be goaded into proving the room right. Nothing about the external event is different. The blame still landed. Everything about the person standing inside it is different, and the whole difference, in Cleanthes' world, comes down to how tightly the soul was strung when the weight came down.
Disclaimer:
Everything IFS Academy is an independent educational platform and is not affiliated with, endorsed by, or connected to the IFS Institute. While we strive for accuracy, errors can occur, and users are encouraged to cross-reference critical information. These courses present the ideas of historical Stoic philosophers for educational and self-reflection purposes only. They describe what these thinkers taught and argued and do not constitute an endorsement of any philosophical position, nor do they constitute religious instruction or professional advice of any kind. They do not constitute therapy, mental health treatment, clinical training, or crisis support, and they should not be used as a substitute for professional mental health care. This course also recounts events from the historical record of Cleanthes' life and death, including accounts of fasting and self-imposed hardship. These are presented as biography and history only. Nothing in this course endorses, recommends, or offers guidance on fasting, food restriction, or any practice that could harm your health, and none of it is medical, dietary, or end-of-life advice.
Crisis Support: 🚨
If you are experiencing a mental health crisis, feel unsafe, feel at risk of harming yourself or someone else, or feel too overwhelmed to safely use self-directed practices, please pause this material and reach out for immediate support. Contact a licensed mental health professional, call or text 988 in the U.S. or Canada, or use your local emergency or crisis resources.
Comments