Stoicism for Humans
We’ve all heard it before: “I’m only human!” people sometimes say when they mess up. Humans aren’t perfect, they’re implying, so give me a break! It’s a common expression. But did you ever stop to think about what it really means to be human? When we say, “I’m only human,” what are we saying about the expectations for our behavior? Does the fact that we are human mean we should think and act differently than if we were spiders, hedgehogs, or extraterrestrials?
It may sound like a silly question because the answer is so obvious. Of course it matters that we’re human. If we were members of a different species, we would be acting completely differently—we certainly wouldn’t be talking about ethics, for one thing! The kind of creature we happen to be makes a big difference not just in our physical bodies but in our capabilities, instincts, and behavior. It may be perfectly appropriate for a black widow spider to kill her mate or a polar bear dad to abandon his cubs, but these behaviors would definitely be inappropriate (and unethical) for a human.
Asking questions about ourselves is something humans have always done; it’s just part of our nature. Philosophers in ancient Greece were asking these same questions more than two thousand years ago, and they reached some very interesting conclusions about human nature that are still relevant for us today. In this milieu the Stoics were singularly successful in creating a compelling, coherent philosophy of life. Through a dazzling combination of empirical observation, logical reasoning, and keen psychological insight, Zeno et al. explained the human condition in a way that can still help us understand how to live a good, happy, and flourishing life.
The ancient Stoics weren’t asking these questions just because they didn’t have smartphones or Netflix to keep them busy. They were sincerely committed to the quest for truth, happiness, and fulfillment. And this search for truth and happiness led them directly into a deep investigation of human nature.
Human nature, they thought, is our guide into what behaviors are natural and appropriate for us. “I mean,” said Seneca,
how will you know what conduct should be adopted unless you have discovered what is best for a human being and have studied human nature? You will not understand what you should do and what you should avoid until you have learned what you owe to your own nature.”
In other words, if we want to know how to live a good human life, we need to understand what makes us human.
One way to do this is to look at the special characteristics and capacities that set us apart from other creatures. Humans are obviously very different from other animals, but in what ways exactly? We don’t have special size, strength, or speed, and most of our features are shared with our nearest living relatives, the great apes. In many respects we are unexceptional. But we do stand out in a few ways, and it’s those characteristics that really make us who we are. Here’s how Seneca put it:
Fruitfulness is the distinctive excellence of the vine; similarly in a human being we should praise that which belongs to him. So what if he has...a lovely home, vast plantations, substantial investments? All these things surround him; they are not in him. Praise in him that which nothing can take away and nothing can confer—that which is distinctive about the human being. Do you ask what that is? It is the mind, and rationality perfected within the mind. For a human being is a rational animal. Hence his good is complete if he fulfills that for which he is born. But what is it that this rationality requires of him? The easiest thing of all: to live in accordance with his own nature. 
Our powerful human brains—the most complex structure in the known universe —host a sophisticated suite of related abilities like language, facial recognition, and inferential reasoning. The Stoics packaged these collectively into the term “rationality,” which is a useful shorthand for our incredible cognitive skills.
Unlike other animals (that we know of, anyway), we humans can reflect on our own condition in life, thinking about our place in the universe, our relationships with other people, and the best course of action for us to pursue. We are not merely subject to the pre-rational instincts that drive most other animals. Somehow, in ways that we still don’t completely understand, we are able to think about our own thinking, and we are able to override instinctive impulses that might “naturally” drive us toward food, sex, or safety.
In fact, it is this ability to override instinctive impulses that ultimately sets us apart from other species and makes us truly human. But this capacity must be cultivated over time in order to reach full fruition. To explain how this happens, the ancient Stoics closely observed human behavior over the lifespan and advanced their brilliant developmental theory of oikeiosis.
According to this theory, nature has created all plants and animals with the drive to preserve and take care of themselves. All creatures have natural capacities and instincts to find food, promote their own safety, and successfully propagate their genes into the next generation. That’s the end of the story for most plants or animals. But for humans, given our extra capacity for rationality, the story gets much more interesting.
Human infants, like other animals, are genetically programmed to seek food, warmth, and the security of a loving caregiver. But as we get older and our rationality develops, we start to understand who we are and our role in the world. We learn that what benefits us as humans isn’t simple self-preservation but rather the fulfillment of our special rational nature. We don’t fulfill our humanity by simply staying alive at all costs, or by seeking pleasurable or comfortable experiences. That’s what pre-rational animals do. As mature humans, we realize our good lies in cultivating those amazing cognitive gifts. Our excellence lies in our rationality, which means it benefits us to preserve our rationality rather than our mere material welfare.
But that’s not all. Human nature doesn’t begin and end with rationality; there is another important component that makes us who we are. The ancient Stoics noted that we are very social creatures, and our ability to form strong, cooperative bonds with others is another key ingredient of our humanity. The Stoics turned to animal comparisons to draw out the instinctual nature of our social gregariousness:
But you will agree that human nature is very much like that of bees. A bee is not able to live alone: it perishes when isolated. Indeed, it is intent on performing the common task of members of its species--to work and act together with other bees. Given that this is so, and given, too, that a wicked person displays injustice and savageness, as well as a lack of concern for a neighbor in trouble, while a virtuous person displays love for his fellow human beings, as well as goodness, justice, kindness, and concern for his neighbor. 
Just as bees cannot properly perform their functions as a bee outside the context of their hive, so humans cannot properly perform the functions of a human outside our community. Sure, there are a few humans who prefer to live as hermits or anchorites, but even these recluses do not exist completely without human contact. Even the most retiring of hermits grew up in a family and/or community and became a fully functioning human in this social context. Without linguistic input and meaningful social interaction as children, for example, we would not be able to speak a language, or develop the bare skills necessary for independent survival.
The fact that humans have the longest childhood of any creature in the animal kingdom—and are so dependent on adult caretakers for so long—is further evidence of our social nature. For the first dozen or so years of our lives we literally would not survive without other people. As a result, children are genetically hardwired to interact with caregivers, read faces, and understand other people’s minds for cooperative purposes.
And we adults are programmed by our DNA to love and care for our children. Why do parents spend 18 years waking up in the middle of the night, dealing with temper tantrums, and picking up dirty socks for our children? Because we love them, of course. But that love doesn’t come from nowhere; it’s part of our genetic endowment. It takes a very strong parental instinct to pick up dirty socks off the floor for 18 years.
But social bonds are not just important for parents and children; they continue to be crucial to our survival and flourishing as adults. Think for a moment about all the ways you depend on other people just for the basic necessities of life. Farmers, manufacturers, and distributors all get your food to you; the power company produces and sells you your electricity; your local and national government supplies the roads that enable access to your home and the laws that provide a stable and secure community for you. Today we depend on thousands of other people just to meet our basic needs, not to mention all those other 21st century “needs” that make our lives so pleasant.
The Stoics duly noted our extreme social instincts, and they realized that part of our excellence as humans depends on how well we interact with others. As Marcus Aurelius—Roman emperor, father of his people, and Stoic philosopher—so eloquently put it: “A human being finds delight in doing what is proper to a human being; and what is proper to him is to show goodwill to his own kind.” 
Our companionable nature is so important to our well-being, in fact, that we demonstrate our excellence by naturally helping other people. Some people may be confused about what’s good for them, mistakenly believing that they should take from others rather than giving. But according to the Stoics, we find our happiness by fulfilling our nature, and we fulfill our nature by doing good for others:
Tell me, man, when you have done a good turn, what more do you want? Is it not enough that in doing this, you have acted according to your own nature, that you should go on to seek a reward for it? It is just as if the eye sought compensation for seeing, or the feet for walking. For as these were made to perform a particular function, and, by performing it according to their own constitution, gain in full what is due to them, so likewise a human being is formed by nature to benefit others, and, when he has performed some benevolent action or accomplished anything else that contributes to the common good, he has done what he was constituted for, and has what is properly his. 
The two cornerstone characteristics of humanity—our rationality and sociability—point the way toward human fulfillment and happiness. If we want to be happy in any meaningful way, we will need to meet the criteria provided by nature. “The nature of each creature determines, after all, the virtue characteristic of it,”  said the great Stoic teacher Musonius Rufus. By fulfilling our capacities for rationality and sociability, we complete our nature, thereby finding the flourishing happiness that results from doing what we are best suited to do.
Once we realize that our happiness is tied to our excellence as humans, we can start to ask different questions. What exactly does this excellence look like, and how do we achieve it?
The ancient Greeks in general, and the ancient Stoics in particular, spent a lot of time trying to describe human excellence. They imagined a hypothetical perfect human—the sage—and thought about what the sage would be like. They didn’t expect anyone to actually become a sage, but they used the idea as a guide for developing personal excellence.
In ancient Greece, excellence of any kind was called arete, which we usually translate today as virtue. In a way this translation is unfortunate because, over the centuries the English word virtue has come to sound a bit stuffy and prudish. It sounds, at best, a bit boring, and at its worst it can apply to someone who wrongly thinks themselves morally superior to others.
But nothing could be further from what the ancient Greeks had in mind. Arete for them was courageous and noble, bold when necessary or restrained when it needed to be. It meant the pursuit of excellence in every arena of life, from the battlefield to the boardroom, from the gymnasium to the banquet hall. Virtue includes practical intelligence, greatness of soul, adroit social relations, and the ability to overcome hardship. Anything good that a person could be is a part of virtue: the characteristic excellence of humanity.
In order to understand and ultimately develop virtue, the ancient Stoics devoted much reflection and many books to cataloging and categorizing different types of virtue. These taxonomies are not so important for us here because we are more concerned with practicing virtues than classifying them. But to give you a taste of how much thought they put into virtue, I want to show you at least one ancient virtue taxonomy. This is one of my favorites, from a later philosopher who wrote about the Stoics :
Of virtues some are primary, some subordinate to the primary. There are four primary virtues: prudence, temperance, courage, justice. And prudence concerns appropriate acts; temperance concerns human impulses; courage concerns instances of standing firm; justice concerns distributions. Of those subordinate to these, some are subordinate to prudence, some to temperance, some to courage, some to justice.
To prudence are subordinate deliberative excellence, good calculation, quick-wittedness, good sense, a good sense of purpose, resourcefulness.
To temperance: organization, orderliness, modesty, self-control.
To courage: endurance, confidence, great-heartedness, stout-heartedness, love of work.
To justice: piety, good-heartedness, public-spiritedness, fair dealing.
You’ll see here the traditional Greek enumeration of four cardinal virtues: prudence (or wisdom), temperance, courage, and justice. If you crack open any book on Stoicism, these are the four virtues you’ll see. They form the foundation of any discussion of classical virtue, and they are just as canonical for Stoics today as they were in ancient times.
But what really stands out for me in this list is how very practical the virtues are meant to be. These are not the characteristics of a solitary meditator or armchair thinker; these virtues are dynamic, engaged in the world, and ready for action. These virtues are ready to roll up their sleeves and lend a neighborly hand. Stoic virtue is clearly not an isolated affair but a practical endeavor that takes place in the context of our daily social interactions.
Contrary to what some people may believe, virtue is not about withdrawing from the world or isolating yourself from others. Virtue is about leaning into life, making the most of what we have, developing our personal excellence by sharing our gifts with other people. We are to be resourceful, stout-hearted, orderly, and public-spirited in daily living. Virtue simply means bringing out the best in our nature as we go about our very human lives.
The very concrete nature of virtue raised additional questions among the ancient Stoics. Is virtue more like knowledge, or more like a skill, or more like a craft? Or perhaps it’s a disposition? I think the clear answer is that it’s complicated. Because humans are so complex, any cognitive property of humans is also going to be complex. The good news is that we don’t have to answer too many theoretical questions about virtue in order to become virtuous, so we don’t need to sweat the answer right now. All we need to do is figure out how to incorporate virtue into our own lives.
And even though virtue is complicated in some ways, there is one aspect of virtue that almost all Stoics agree on: its unity. Although we speak of virtues in the plural, and we assign them different names and characteristics, these enumerated virtues are actually just different faces of one thing. “For all the virtues consider the topics of all the virtues,” according to one ancient source. “All the virtues make being happy their goal (and this lies in living in agreement with nature) but each virtue achieves this in a different manner.” 
The virtues all mutually inform and imply one another, meaning there is a lot of overlap and repetition. That’s because in order to truly have one virtue, you would need to have all the others. Virtue is a holistic mental condition, a way of looking at and experiencing the world. A virtuous person in the full, Stoic sense of the word would have perfect judgment at every moment of her life, and everything she did would be virtuous.
Remember, though, the Stoic sage is a hypothetical ideal, an aspiration, and not a condition we expect ourselves to fully reach. Since virtue is the perfection of human nature, it would probably take many lifetimes to achieve true perfection.
As a result, virtue is an all-or-nothing condition: either you have it completely, or you don’t have it at all. It indicates a phase change, like when liquid water turns to ice or gas. Water can’t be in two states at once—it's either a liquid, solid, or gas, and there is no in-between. Likewise, a virtuous person couldn’t be partially virtuous and only do some things in a virtuous way. A person has either perfected their judgment or they haven’t. From a Stoic perspective, there is no in-between.
But even though we may never be completely virtuous, that doesn’t mean we can’t make progress toward virtue. Water does not experience a phase change from liquid to gas until it reaches 100°C, but it certainly does have to get hotter to reach that point. You might say water at 95°C is much closer to boiling than water at 5°C. In the same way, you and I may never reach the boiling point of virtue—if you’ll forgive the crude metaphor—but we can definitely get warmer.
Just remember, as you aspire toward virtue, to go easy on yourself when you sometimes mess up. Because you will mess up. Sometimes in big ways, sometimes in small, but trust me, imperfection is the one constant in this quest. That’s ok, though, because the main point is that we are trying to improve ourselves and our lives. When we make mistakes we can forgive ourselves in good conscience and move on. We may not be perfect, but in our own way we are still moving in the right direction.
And you if you stay true to your purpose, you will definitely move in the right direction. It won’t always be easy, and it won’t always be obvious, but you will make progress. As the wise and wonderful Epictetus once said, “See if there is anyone among us who, if he strives to keep himself and his life in conformity with nature, fails to make progress. You won’t find anyone who fails to do so.” 
As you embark or continue on your Stoic journey, keep reminding yourself why you started in the first place. What is your motivation for sticking to this hard, demanding path? If you can’t clearly articulate your motivation to yourself, you may not be able to stay committed. For me personally, my motivation is clear: I want to be happy, and this is the best path to happiness I have ever found. As Musonius Rufus reminds us, “There is no other reason for becoming good than to be happy and to live a blessed life thereafter.” 
Or as Seneca puts it, in his characteristically ringing tones :
What is a happy life? It is security and lasting tranquility, the sources of which are a great spirit and a steady determination to abide by a good decision. How does one arrive at these things? By perceiving the truth in all its completeness, by maintaining orderliness, measure, and propriety in one's actions, by having a will that is always well-intentioned and generous, focused on rationality and never deviating from it, as lovable as it is admirable. Let me sum it up for you like this: the wise person should have the sort of mind that would befit a god.
If you’re the sort of person who would enjoy “the sort of mind that would befit a god”—not to mention long-lasting tranquility, a great spirit, and the perception of truth in all its completeness—then I invite you to join me in the pursuit of Stoic virtue. Even though we won’t achieve perfect happiness, we can become much happier than we were before we started. We will be better humans for having tried.
1. Seneca, Letters on Ethics, 121.3
2. Seneca, Letters on Ethics, 41.7-8
3. “Decoding ‘the Most Complex Object in the Universe.’" Science Friday with Ira Flatow. Quote from Christof Koch, Allen Institute for Brain Science. https://www.npr.org/2013/06/14/191614360/decoding-the-most-complex-object-in-the-universe
4. Musonius Rufus, Lecture 14.3
5. Marcus Aurelius, Meditations, 8.26
6. Marcus Aurelius, Meditations, 9.42
7. Musonius Rufus, Lecture 17.1
8. Stobaeus, 5b2
9. Stobeaeus, 5b5
10. Epictetus, Discourses, 3.6.4
11. Musonius Rufus, Lecture 7.3
12. Seneca, Letters on Ethics, 92.3