What does it mean to live according to nature?

The Stoics, the Platonists, and the Epicureans agreed: we should live in agreement with nature. But what does that mean?

Image from nature.org.

“Again, to live according to virtue is equivalent to living according to the experience of natural events, as Chrysippus says in the first book of his work On Goals. For our natures are parts of the nature of the universe. This is why the goal becomes to live according to nature, that is, according to our own nature and that of the universe.” (Diogenes Laërtius, Lives of the Eminent Philosophers, VII.88)

Chrysippus of Soli, the guy mentioned by Diogenes Laërtius in the quote above, was the third head of the Stoic school, and one of its most influential exponents. But other prominent Greco-Roman philosophers, including the Platonist Cicero and Epicurus, agreed with the general sentiment: we ought to live “in agreement with nature.”

Meaning what, exactly? There is a lot of confusion about this catchy phrase that is justly considered a crucial mantra for the Stoics. I’m going to try to clarify why the phrase does not mean at least three things that it is sometimes taken to mean, finally arriving at what I think is a good and useful sense in which it should be taken.

I. No tree hugging

The first thought that might come to a modern reader upon hearing that we should live in harmony with nature is to run naked into a forest and start hugging trees. Or if not that, at least that the phrase refers to some kind of conscious environmentalism that we ought to practice.

As much as a healthy respect for the environment is surely a good idea, and even though naked tree hugging could be fun (depending on the weather), this is most definitely not what the ancient Stoics understood Chrysippus to be advising.

If anything, the Stoics—together with many other philosophical schools—thought that nature is the result of some kind of intelligent providential design. From which it followed that plants and animals are around in order to serve human needs, a position that is hard to reconcile with modern environmentalism (though some of my colleagues have tried).

II. No appeal to nature

The second, and most common, misconception about living according to nature is that it means that whatever is natural is ipso facto good. That notion, however, ought to be easy to reject, since it corresponds with a well known logical fallacy known as the appeal to nature.

That natural does not equal good and, conversely, that “unnatural” (meaning, made by humans) does not mean bad is easy to demonstrate by example. A lot of entirely natural living organisms are very dangerous for our health, from several viruses and bacteria to poisonous mushrooms. Moreover, many artificial creations are clearly good for us, like vaccines and scores of medicines.

Of course, there are also examples of natural things that are good for us (lots of foodstuff, like leafy vegetables, lean meat, etc.) and of artificial things that are not (tons of industrial chemicals, social media). So no straightforward connection can be made between natural / artificial on the one side and good / bad on the other side.

III. Yes, we can derive an ought from an is

Things get a bit more tricky when people start talking about the naturalistic fallacy, a possibility famously raised by David Hume in A Treatise of Human Nature (1739), where he wrote:

“In every system of morality, which I have hitherto met with, I have always remarked, that the author proceeds for some time in the ordinary way of reasoning, and establishes the being of a God, or makes observations concerning human affairs; when of a sudden I am surprised to find, that instead of the usual copulations of propositions, is, and is not, I meet with no proposition that is not connected with an ought, or an ought not. This change is imperceptible; but is, however, of the last consequence. For as this ought, or ought not, expresses some new relation or affirmation, it’s necessary that it should be observed and explained; and at the same time that a reason should be given, for what seems altogether inconceivable, how this new relation can be a deduction from others, which are entirely different from it.”

It isn’t entirely clear whether Hume was arguing that one cannot bridge the is/ought gap, as it is often called, thus deriving values from facts. But he certainly did point out that if someone does that then they owe us an explanation of how, exactly, they make the connection.

Sometimes we find modern scientists and science popularizers, like Steven Pinker, getting on board with the notion that bridging the is/ought gap is fallacious:

“The naturalistic fallacy is the idea that what is found in nature is good. It was the basis for social Darwinism, the belief that helping the poor and sick would get in the way of evolution, which depends on the survival of the fittest. Today, biologists denounce the naturalistic fallacy because they want to describe the natural world honestly, without people deriving morals about how we ought to behave (as in: If birds and beasts engage in adultery, infanticide, cannibalism, it must be OK).” (Q&A: Steven Pinker of ‘Blank Slate’)

But Pinker here is making a mistake, describing the appeal to nature and confusing it with the (alleged) naturalistic fallacy. They are not the same thing, because to say that our values can be derived from facts about nature is not at all equivalent to simply stating that whatever is natural is also good. Indeed, if we don’t get our values from facts about the natural world, where do we get them from?

IV. Naturalistic ethics and its rivals

Let’s step back for a moment and ask ourselves the sort of question that philosophers gleefully use fancy language to describe. Let us talk about meta-ethics!

Meta-ethics is the study of the nature of ethics itself. Roughly speaking, there are three ways to look at it: realism, anti-realism, and naturalism. Although they all come in a number of varieties, these are pretty much the only three games in town, so to speak.

Realism is the notion that there are mind-independent ethical truths “out there.” It usually comes in two major flavors: either such truths originate with some god or other, or we arrive at them by exercising reason.

The first option has, in my mind, been dispatched by Plato in his Euthyphro dialogue. There Socrates converses with a self-important priest named Euthyphro, who is sure that he knows what is moral (“pious”) because he thinks he knows what the gods want.

Socrates, naturally, begins to question Euthyphro and arrives at the crucial question: is something moral because the gods say so, or do the gods say that something is moral because it is so? In the former case, the first horn of what is nowadays known as Euthyphro’s dilemma, morality turns out to be arbitrary, a case of might makes right. The gods, after all, may change their mind tomorrow and decree that genocide, say, is moral. And we would have no choice but to accept this turn of event or else.

In the second case, by contrast, we are acknowledging that gods have nothing to do with morality, and that even they determine what is and is not moral on the basis of an external criterion. If that is so, says Socrates, perhaps we can discover such criterion on our own, no middle gods necessary.

Though scores of theologians have tried to deny the power of Euthyphro’s dilemma, as far as I can tell they have all failed. If you think morality is objective, it does not come from divine decrees, so gods are out of the picture.

Perhaps, then, we can use reason—as Socrates hinted at—to figure out what is and what is not moral. That version of moral realism has been endorsed by Kant, for whom ethics is akin to mathematics or logic. We can directly grasp mathematical, logical, or ethical truths by way of our thinking faculty.

But that’s more than a bit weird. A number of philosophers are already not convinced that realism is true for math and logic, both of which can more easily be interpreted as human-invented systems capable of dealing with a wide range of problems. But morality? Why would there be universal moral laws in the first place? How, exactly, are we able to grasp them? What is their ontological status, and what sort of epistemic access to them do we have?

The philosophical difficulties in defending a coherent and plausible version of moral realism is what has brought many philosophers over to the opposite camp, anti-realism, according to which morality is an arbitrary human invention.

Moral anti-realism comes in a variety of forms, from straightforward moral relativism (genocide? eh, your opinion, my opinion) to emotivism, according to which when we say that something is immoral we are simply expressing an emotional reaction akin to disgust, to so-called error theory, wherein whenever we make a moral judgment we incur in a category mistake, because there is no such thing as moral truths in the first place.

And yet, the anti-realist stance isn’t that much more convincing than its realist counterpart. Very few, if any, people actually behave as relativists: as soon as what the rest of us would call an injustice is done to them they start screaming bloody hell and invoke all the trappings of moral talk. And emotivism, for one, isn’t incompatible with our third option, which I am about to briefly explain.

That third option is ethical naturalism, a position implicitly invoked by pretty much all the Greco-Roman philosophical schools and re-articulated nowadays by philosophers like Filippa Foot and scientists like Frans de Waal.

The basic idea is that ethics, or morality (you may have noticed that I’m using the two terms interchangeably [1]) is a naturally evolved behavioral pattern that we have in common with other social primates.

After all, what is the point of moral talk? To solve the problem of living together with other members of our species in a way that is mutually beneficial to all. Bonobo chimpanzees, gibbons, orangutans, tamarins, and others have that problem, just as we do. Accordingly, natural selection has provided them with a range of pro-social instincts, including an innate drive toward cooperation and a pre-reflexive sense of fairness.

When it comes to human beings, however, nature has given us the building blocks of morality—which we share with our primate cousins—and also the ability to explicitly reason about the problems of coexistence characteristic of complex societies featuring hierarchies and division of labor. That is, in the human case we have both biological and cultural evolution contributing to shaping our ethics.

As both Seneca and Cicero explain, this is very much the Stoic position: Nature gives us the beginning of virtue, meaning an instinct for pro-social, cooperative behavior toward other human beings. Once we reach the age of reason we are then in a position to expand our circles of ethical concern beyond our close relatives and friends to broader and broader sets of humanity, ideally embracing cosmopolitanism, the notion that all human beings—regardless of their ethnicity, gender, or whatever—ought to be treated with fairness and respect.

V. Like cacti, so human beings

Given all the above, what sense can we finally make of the Stoic (and Epicurean, and Platonist) phrase “live according to nature”? The same sense a cactus would, if it were sentient.

Let me explain. Suppose you are kind enough to invite me over at your place for dinner. Since I’m a polite guest, I show up with a gift. I bring you a nice bottle of wine, say an Amarone, and—to brighten your living room—a cactus.

The wine we’ll merrily drink together, but you are from now on responsible for the wellbeing of the cactus. Which means you need to learn a bit about what allows cacti to flourish. Since they are plants, of course they need soil with certain nutrients, water, and light. But since they are desert plants, the light needs to be plentiful while the water has to be only occasional, otherwise the cactus will die.

The point is that if you care about your cactus flourishing then you need to provide certain things for it, and you are constrained in doing so by the specific biology of the cactus. If it were a different kind of plant you’d give it a different combination of soil nutrients, water, light, and so forth.

The same goes for human beings. If we want to build a society were people flourish then we need to consider what sort of animal Homo sapiens is: highly social, and highly intelligent. A certain number of things—say, people randomly stealing from or killing other people—will get in the way of human flourishing. Conversely, other kinds of things—for instance education, health care, availability of friends, good jobs—will be conducive to a good human life.

Notice two important details here. First, I phrased our concern for both cacti and humans in terms of if … then clauses. These are what Philippa Foot calls conditional imperatives. Morality is built on conditional, not categorical, imperatives. That is, moral “truths” are not absolute—like the truths of math and logic—but instrumental. If you are a psychopath you will reject the if clause and refuse to act ethically. And the rest of us will put you in an asylum for the mentally ill.

Second, knowledge of human (or cactus) nature will constrain but not uniquely determine the answer to moral questions. There is more than one way to flourish as a cactus, and many more ways to flourish as a human being. But these ways are not arbitrary, as the relativist would have it, but rather bounded by certain facts about human (or cactus) nature. And that’s how we “derive” values from facts in moral philosophy.

If you followed me all the way here you may be interested in making one more connection concerning this subject matter. Talk of living according to nature is tightly related to—indeed, synonymous with—talk of natural law, a concept that has been articulated by Greco-Roman writers like Cicero and that has influenced Medieval Christianity, the Founding Fathers of the American Republic, and the United Nations Declaration of Universal Rights.

The phrase “natural law” is, unfortunately, a bit too strong, as it makes it sound like morality works in a rigid and exceptionless fashion, like the laws of physics. It should be clear from the above discussion that that’s not the case. Rather, natural law simply means that there are certain behaviors that are unacceptable if the goal is to build a society of flourishing human beings and other behaviors that are, by contrast, highly conducive to it. By now you have a good idea of what such behaviors may be.

The problem, or perhaps the advantage, of thinking of ethics in terms of living in agreement with nature, is that the approach underdetermines the actual range of behaviors that is or is not acceptable. (Or, in the case of natural law, it underdetermines so-called positive, that is human, law.) The Greco-Romans were aware of this, which is why they repeatedly stated that Nature gives us the outlines of virtue but that it is up to us to work out the details—within the general parameters set out by human nature. Let’s get to work, shall we?

_____

[1] Cicero translated the Greek êthos into the Latin moralis, and both terms refer to individual character and to customs pertinent to social living.