I think humans are exceptional. To many, this may seem naïve or chauvinistic. Surely, studies in animal behavior (ethology) have conclusively shown that all the attributes previously thought to mark out humans as distinct from other animals—e.g. language, tool use, culture—have been discovered in dolphins, crows or chimpanzees.
Well, those ethologists can pack a lot into their definitions. If you define tool use broadly enough, it can include both the sticks trimmed by crows to catch insects and laparoscopic surgery; the octopus’s use of a coconut shell as a shelter and a 3D printer; the rocks otters use to smash open abalone shells and the Large Hadron Collider.
Given a sufficiently loose definition, it’s possible to find examples of other animals with all the supposedly unique capacities of humans. But there remains a gulf in terms of the complexity, variety and adaptability of human capacities compared to those of other animals. It’s a difference of degree rather than kind—but a significant difference nonetheless.
More importantly, there is a vast disparity between the human impact on the world, and on other species, and that of our animal cousins. Humans have an exceptionally destructive effect on the environment. But, rather than prompting self-flagellation, this can provide a spur to environmental action.
Humans Are Exceptional—For Now
Consider language. Chimps need to be taught by dedicated human experts for years before they can learn ten hand signs. The claim that they know American Sign Language (ASL) is false—as people who know ASL have always known it to be. Like all natural human languages, ASL has a complex grammar, which allows phrases to be embedded within other phrases; permits various sentence structures (e.g. subject–object–verb); allows for the coining of new compound words; and permits puns, poetry and all the prodigious opportunities for communicating complex ideas that human language affords. By contrast, chimps are able to join only two words—or sometimes three—to form phrases like banana eat give—and this is a charitable interpretation of their grammar.
I’m not here to denigrate chimps. They are extraordinary animals—exceptional. And that’s the point. Chimps have been selected to disprove human exceptionalism because they are themselves an exceptional species. You couldn’t rein in human overconfidence by comparing us to a species of nematode worm. Not that there’s anything wrong with nematode worms either. What makes anything a species is the fact that it’s exceptional in some way: if it weren’t—at least genetically—it wouldn’t be a distinct species. However, although all animals are exceptional, some are more exceptional than others.
Humans are particularly exceptional. This is not a spiritual fact, merely a historical one. Indeed, I couldn’t have made this claim 50,000 years ago. Back then, there were not only chimps around to remind us of our evolutionary heritage, but Neanderthals, Homo floresiensis (the hobbit) and Homo erectus. All three of these hominid species were tool-using, fire-using, language-using (probably), clothes-wearing and perhaps even had their own cultural myths about their own species’ exceptional status. But because those branches on the tree of life have been pruned, we are somewhat more exceptional today, simply because our closest relatives are extinct.
Nor is our relatively exceptional status guaranteed to remain so in the future. An encounter with intelligent aliens would be the most obvious way for our ego to take a hit. The invention of a truly intelligent AI would have the same effect. There’s also nothing in the evolution rule book prohibiting other terrestrial species from evolving into more intelligent new species, given enough time. Indeed, we may start changing ourselves—through genetic engineering and other forms of modification—and perhaps even branch off into separate species of artificially bred humans. In the future, we might return to a state in which there are multiple coexisting species that truly share our currently exceptional traits, such as the use of complex language.
The Irony of the Anthropocene
If we envision the tree of life, containing every species that has ever lived, the most salient fact is that, to within a rounding error, life is microbial. The second most obvious lesson is that there is nothing essential about any species. Speciation happens over eons, through minute changes to genomes. These changes manifest as differences in bodies and behavior.
We’re made out of the same atoms and molecules and many of the same proteins as plants, animals, fungi and even single-celled organisms. We even have a lot of genes in common. The crucial differences are not in what we’re made of, but in what we do. Even the most ardent human exceptionalism skeptic has to concede that the impact of Homo sapiens on the planet and on other species has been gigantic.
Hence the irony of the Anthropocene. The very name of this epoch enshrines anthropocentrism. It acknowledges that humans have an outsize influence on the earth’s climate and even geology. And yet the rhetorical aim of giving the epoch this name was to encourage humility and lessen human arrogance. Some environmentalists worry that calling it the Anthropocene implicitly frames human industrial activity as both the problem and the solution. If large-scale industrial activity got us into this mess, then perhaps geoengineering will have to get us out. In my experience, almost all environmentalists are aghast at the idea of further intervention in the Earth’s complex systems, many of which we’ve already damaged irreversibly.
There is a parallel irony in those studies of animals that aim to disprove human exceptionalism. Take the wonderful videos of the Caledonian crow combining two twigs to make a compound tool, in order to extract some food from an enclosure. But note that the more effort researchers go to prove animal skill the more they undermine their case. The cameras, the detection devices, the experimental set-up to entrap the crow into using tools in a certain way, the peer-reviewed journals that report on its behavior, the scientific method, the internet via which you watch the video—all of this is necessary to Homo sapiens’ investigation of Corvus moneduloides. But the crow cannot develop any of those things and is unable to investigate Homo sapiens or any other species in the same way. The point is not that only we can use tools: clearly some other species can too. The point is what we do with those tools. This is not a metaphysical question, but simply an empirical fact: we use exceptional tools in exceptional ways.
This is not a question of morality. Although I’m advocating the notion of human exceptionalism—as a descriptor of our currently unique status—I’m not necessarily advocating humanism as an ideology. There are plenty of valid anti-humanist arguments out there. Some, like those advanced by the philosopher John Gray, emphasize our atrocious record in defining who is and isn’t human and the savage treatment of non-white people on the grounds of being sub- or non-human. Other philosophers, like Donna Haraway, argue that humanism obscures the agency of nonhuman animals and that we should be moving to a post-human perspective.
Humanism is also scientifically dubious, as it seems to imply essentialism. There’s no bright dividing line between us and our near relatives. Only historical accidents—and perhaps some killing on our part—have resulted in the extinction of our closest kin, the other hominids.
In practice, humanism is pretty benign, however, because it tends to be non-dogmatic and aims to decrease suffering and increase human flourishing. On balance, if more humans were humanists this would undoubtedly be a better planet. But humanism’s philosophical foundations are shaky.
Some critics fear that, by recognizing humans as unique, albeit not essentially different, we will fail to treat other animals properly. This implies that we should only treat animals well because they are no different from us. But, surely, we should treat other life forms in ways that actually have something to do with their natures. In fact, even environmentalist vegans (like me) do this in practice. Bivalve vegans eat oysters, but not cows, reasoning that oysters don’t really have nervous systems and so the notions of pain and bodily suffering aren’t applicable to them. Even those who baulk at eating oysters still eat plants, fungi and bacteria. Everyone, including vegans, tacitly endorses some kind of scala naturae, or ladder of being. But people—and currently only people—disagree over the rungs.
Among the effects humans have on the planet, one truly significant difference quickly looms into view. Our planet is totally unlike every other planet we know of—because of the effects of living things on its surface and atmosphere. From the cyanobacteria, which produced the oxygen in our atmosphere about two billion years ago, to the population explosion of cattle, which is increasing its methane content and contributing to global warming, some species have exerted an unusually large effect on the globe. Homo sapiens more so than anything else. Even the effect of the cows is owing to humans.
The difference between our planet and any other is therefore of a far greater degree than the difference between any two species on our planet. Yet a large part of what makes the Earth unique has been caused by one species. And, in some far future, when we have further terraformed Earth, the impact of Homo sapiens will be still more noteworthy, even on a cosmic scale. This impact won’t necessarily be good. It could result in nuclear winter or catastrophic climate change; it could involve rewilding the Earth; it could take the form of a giant biodome project. But, one way or another, the shape of the Earth will probably be determined by human activity.
When it comes to figuring out how we can help the planet, we have to accept the exceptional status of humans in terms of how much we are able to modify the environment. This is not the same as saying we have some god-given warrant to treat other species however we want. Nor is it an avowal of a spiritual mission to save the world. Instead, it is an approach born of pragmatism and compassion. We are better able to help other species than they are (even if we were responsible for the harm that came to them in the first place).
Veganism, lab-grown meat, wildlife sanctuaries, world heritage sites, carbon sequestration, reintroductions of keystone species and perhaps even geoengineering—these are all interventions in the biosphere, of varying degrees of riskiness. In the future, we might also be able to revive recently extinct species or genetically enhance current ones to aid their survival in the fight against diseases or changing climates. As an even more fantastical favor to life on Earth, we might one day be able to deflect an asteroid otherwise destined to wipe out all multicellular species.
None of this will provide a way to atone for past sins against other species. Our track record is certainly grave: between polluting waterways, killing off megafauna, causing the sixth extinction, increasing the greenhouse effect, overfishing, torturing animals on an industrial scale and destroying many, many habitats—haven’t we done enough? In light of such a history, how can I be so tone deaf as to assert human exceptionalism and hubristically claim that we should further deliberately intervene in the environment?
Figuring Out What We Value
We need to clarify what the goals of environmentalism are. Most people are familiar with somewhat vague notions of increasing biodiversity, increasing sustainability or treating all living things equally. Such messages have to be simple for campaigning purposes. But if you put any pressure on them they start to crumble. For example, if biodiversity is inherently good, what would it look like to increase it? Do we want as many species as possible? Should we genetically engineer new ones? Nature itself is the biggest destroyer of species, so should we intervene to stop species going extinct naturally? Or is biodiversity best measured at the level of genomes? After all, most life is microbial, so would a world with fewer plants and animals but more genetically diverse microbes be somehow preferable?
Or perhaps, as proponents of deep ecology advocate, all life forms should be given equal moral consideration. But in what sense is the bacterium equal to the panda? Again, would we assess this in terms of genome, species, individuals, biomass or something else?
By the 1980s, soon after the dawn of ecological thinking, environmental philosophers like Val Plumwood and Warwick Fox had already recognized that these kinds of goals are ill defined—and were hashing out better ideas. In an article from 1984 called “Deep Ecology: A New Philosophy of Our Time?” Warwick Fox tried to put deep ecology on a more philosophically justified basis: “The only universe where value is spread evenly across the field is a dead universe.” Fox argues that, rather than blanket equality, which leads to such absurdities, “organisms are entitled to moral consideration commensurate with their degree of central organization.”
It’s not that ranking organisms according to their “degrees of central organization” is the way we should think about environmentalism or our place in nature. But it’s the type of candidate concept we need, in order to parse out these issues more clearly. Talk of human exceptionalism grates because of the profoundly negative impact humans have had on other species. But that impact is, frankly, quite exceptional.
We could aim to return to small-scale agrarianism or tribalism as a way to return to a mythic Golden Age when all species were equal. But this prelapsarian time never existed. There have been at least five earlier great extinctions. Almost every species that ever existed also went extinct, even without our help. But when the asteroid comes, or the supervolcano explodes, or the gamma ray burst threatens, there is currently only one species with the resources to know what’s happening and, more importantly, to be able to do something about it.
We humans are in an unprecedented position. We are finally learning about the nature of life and about how precious this planet is. So far, only we can learn such things. By doing so, we can arrive at a compelling and nuanced reason to galvanize us to do what we already know is right: preserve the biosphere. Not because it’s harmonious or magical, but because it is a fragile and strange oasis of complexity in an otherwise unending desert of mere matter and energy. Why do we value the biosphere we’re a part of? Because values of any kind—no, value itself, is possible only because of this tree of life from which we evolved.