IF NIETZSCHE WERE A NARWHAL: What Animal Intelligence Reveals About Human Stupidity
By Justin Gregg
320 pages. Little, Brown & Company. $29.

“Human, all too human”: It’s a thought that occurred to me a few times while reading Justin Gregg’s “If Nietzsche Were a Narwhal,” and not just because the phrase also happens to be the title of a work by Nietzsche himself. Gregg’s clever and provocative book is full of irreverent notions and funny anecdotes — the creative upside to being a human animal. But our ability to abstract from our immediate experience means we can take that creativity too far.

“If Nietzsche had been born a narwhal,” Gregg writes, “the world might never have had to endure the horrors of the Second World War or the Holocaust.” Say what? This seems to be a sterling example of what Gregg calls our species-specific penchant for “unexpected ludicrousness.”

Such rhetorical contortions are probably the consequence of what he derides as our obsession with causal inference. Nonhuman animals get by just fine on “learned associations.” They link actions with results, without having to understand why something is happening. Humans, though, are “why specialists.” We need to look for causal connections — leading to some incredible achievements but also to some bizarre practices. Gregg points to the old medieval remedy of rubbing a rooster’s keister on a snakebite wound.

Gregg studies animal behavior and is an expert in dolphin communication. He shows how human cognition is extraordinarily complex, allowing us to paint pictures and write symphonies. We can share ideas with one another so that we don’t have to rely only on gut instinct or direct experience in order to learn.

But this compulsion to learn can be superfluous, he says. We accumulate what the philosopher Ruth Garrett Millikan calls “dead facts” — knowledge about the world that is useless for daily living, like the distance to the moon, or what happened in the latest episode of “Succession.” Our collections of dead facts, Gregg writes, “help us to imagine an infinite number of solutions to whatever problems we encounter — for good or ill.”

“If Nietzsche Were a Narwhal” is mostly fixated on the ill, or the way that humans insist they are improving things when they are ultimately mucking them up. There is already a stuffed shelf of books about how we aren’t as smart as we like to think we are, or how our smartness can lead us astray: David Robson’s “The Intelligence Trap,” Leonard Mlodinow’s “Emotional,” books in behavioral economics by Daniel Kahneman or Dan Ariely. But Gregg makes a bigger case about how human intelligence has deformed the planet as well. He explicitly ventures into the conflict between optimists like Steven Pinker and pessimists like the British philosopher John Gray.

Complex thought often turns out to be a long-term liability, Gregg says. The big brains that have allowed us to proliferate as a species, domesticating the natural world, have also empowered us to wreak so much ecological havoc that we’ve unwittingly created the conditions for our own extinction. Fossil fuels have generated prosperity while hastening an apocalypse. Human ingenuity has been used to discover penicillin and to commit atrocities. Surveying the chickens in his yard, Gregg correctly predicts that they’re highly unlikely to “unite en masse to rain death down upon the world in pursuit of glory for the Great Chicken Nation.” Humans, though, are another matter. “Narwhals,” he points out, “do not build gas chambers.”

True enough, and it’s worth thinking about how much trouble humans can create when our ambitions extend beyond our immediate needs. But Gregg, in his very human desire to dramatize the stakes, can be prone to overstatement — occasionally glossing over the animal experience while demonizing the human one. We might not be in any danger of chickens creating the Great Chicken Nation, but they do have a literal pecking order. Gregg notes that his chicken Shadow is always the first to grab any food that he tosses into the coop. Dr. Becky eats last. Gregg marvels at how stable their social structure is. Stable, yes; but is it just?

Leave it to a human to ask a question about justice, which has nothing to say about natural selection, or what Gregg calls “the great arbiter of usefulness.” Humans can agitate for change and even revolution because they can imagine a reality that doesn’t exist. It’s not as if Gregg rejects this truth, but he’s mostly writing in a more polemical vein than an exploratory one. He extols how much “happier” and “healthier” we would be if we followed the lead of nonhuman animals but he doesn’t touch on how, well, ableist nature can be: The sick, the weak and the old rarely stand much of a chance in the wild.

Humans can also be surprisingly cooperative. The primatologist Sarah Blaffer Hrdy has noted that humans will regularly spend hours together on a crowded airplane without (usually) resorting to violence, whereas when she envisions a planeload of chimpanzees, “bloody earlobes and other appendages would litter the aisles.” Gregg warns us against being too impressed with ourselves, since unlike human animals, chimps have never been observed killing “every” member of a rival group. While chimps can be murderous, they’re not genocidal. Humans cooperate, which sounds nice, but too often we cooperate with some people in order to destroy others.

On the other hand, we can sometimes go to decidedly “unnatural” lengths in order to extend compassion to strangers, or even to other species. Human existence isn’t inherently good or evil; despite Gregg’s comic distortions — which are undeniably entertaining — the more subtle suggestion that courses through his book is that, compared with nonhuman animals, our existence is more extreme. In addition to chickens, Gregg keeps honeybees. The male honeybees, or drones, are equipped only to mate: Their tongues are too short to allow them to extract nectar, and they don’t have stingers that would enable them to protect the hive. So after the drones have done their work of mating with new queens from other colonies, the female bees will push them out.

These helpless drones will starve or freeze to death, in what Gregg calls “a tragic — but utterly natural — state of affairs.” He takes pity on them, placing them in a box on his deck with some honey, providing them with a respite before their impending doom. “I want to give them one final moment of happiness,” he writes. I’d like to see a narwhal try to do that.