The Belief Instinct: The Psychology of Souls, Destiny, and the Meaning of Life (4 page)

A handful of more reluctant scholars, however, worried that in trying to show just how human other animals are, we might end up overlooking something equally important. Isn’t it possible, they countered, that despite this striking overlap in behavioral similarity with other primates, human minds still work in this very different, mind-reading way? After all, when compared to the brains of the other African apes, cognitive neuroscientists have found that the area of the brain believed to be responsible for reasoning about other minds is significantly larger in human beings and occupies more of our cerebral mantle. This area, right behind your forehead, is called the prefrontal cortex, and images from functional MRI (fMRI) studies suggest that it houses special neural systems dedicated to theory of mind.

So although the previous century had seen Darwin’s theory of evolution forcing people to come to grips with their own unprivileged, amoebic origins, and more recent studies showed just how much we have in common with other animals, a few academics were beginning to think that, perhaps, there’s still one thing—theory of mind—that makes our species truly unique.

Ironically, such scholars found themselves in a definite minority. The tide had turned. People who now subscribed to the view that humans are “special” carried a suspicious whiff of bias and were looked at askance by the larger scientific community. Many saw them as being either secretly religious and endorsing an outmoded view of the natural world or, even worse, simply not “getting it” when it came to the standard processes of evolution by natural selection, which implied a basic continuity in function and form between members of shared ancestral lineages. After all, hadn’t Darwin himself written that “the difference between the mind of the lowest man and that of the highest animal is…one of degree and not of kind”?
²¹

In a 2004 article in the journal
Animal Law
, Roger Fouts, a psychologist from Central Washington University who had been involved with some of the pioneering sign language work with chimpanzees back in the 1960s, argued for new legislation that would dissolve the “delusory” species barrier between humans and great apes—a legal action that would, in effect, grant personhood status to simians. Fouts writes that in accepting the foregoing Darwinian logic, we can finally

Fouts inveighs against those disbelieving, coldhearted scientists who have “indulged in such pandering [of human uniqueness] to human arrogance,” especially those of the past century who “did not have the excuse of being ignorant of Darwin.” Such a point of view, he reasons, “is derived from our long established theological, political, and metaphysical beliefs about humans.” Fouts confesses that he, too, was once sadly just like these sanctimonious and delusional academics. But after decades of devotedly raising, studying, and interacting with a chimp named Washoe—who was captured as an infant in Africa, her mother killed by poachers—he’s had to come face-to-face with the harsh emotional realities of Darwinian continuity:

Fouts’s story is very touching. But is there any scientific substance to what he’s saying? Perhaps the real issue, some might balk, isn’t about vanity and human arrogance, or about the Cartesian delusion of souls being nestled somewhere in our pineal glands, but instead about biological diversity and the possibility of there actually
being
genuine psychological differences between humans and other animals. It’s not a matter of whether other animals, such as chimps,
have
minds or whether they feel emotions deeply. Nobody’s really debating that. For any credible scientist at least, it’s certainly not a matter of whether humans are “better” or “more evolved” than other species or any such erroneous linear nonsense.

Actually, the only big, juicy question at hand is whether other animals are endowed with a theory of mind. Psycholinguist Derek Bickerton from the University of Hawaii suggests that, were it not politically incorrect and were scientists not unfairly portrayed as foolish little men luxuriating in the delusion of human supremacy, the massive cognitive differences between our species and other animals would be obvious to all. He claims the trouble is that even alluding to the possibility that human beings are unique these days falls “somewhere between Holocaust denial and rejection of global warming.”
²⁴

But after all, a lot has transpired over the past six million years, which is about how long ago it was that we last shared a common ancestor with chimpanzees. Some twenty intermediary human species, from the hairy australopithecines onward, have come and gone over that long time span. Our brains tripled in size, we became striding bipeds (walking fluidly on two legs), and our skulls, pelvic girdles, hands, and feet were dramatically retooled. Certainly this was enough time for natural selection to carve out more or less unique brain-based cognitive properties too—properties that might explain just why our species stands apart so radically today. Perhaps theory of mind can best be understood as a human psychological adaptation similar to other recently evolved physical traits, such as our specialized skulls, hands, and pelvises.

In fact, systematic reconstructions of the human fossil record and painstaking analyses of ancient dwelling sites led cognitive archaeologists Frederick Coolidge and Thomas Wynn to question whether even Neanderthals had a theory of mind. And if chimps are the equivalent of our distant cousins on the evolutionary tree, Neanderthals are something like our fraternal twins. In
The Rise of
Homo sapiens:
The Evolution of Modern Thinking
(2009), Coolidge and Wynn point out that a conspicuous clue to the Neanderthals’ theory-of-mind abilities, or rather their absence, is the fact that they didn’t seem to gather socially at the most obvious place for a meeting of the minds:

Some scientists believe that the evolution of theory of mind in humans but not other living primates might be analogous to the evolution of bat echolocation, where this bio-sonar capacity for navigating and hunting in the dark is present in one of the major suborders of bats (Microchiroptera) while almost completely absent in the other (Megachiroptera). And none have toed this line of human uniqueness more so than a charismatic yet cantankerous researcher from Louisiana named Daniel Povinelli. Appearing on the scene in the early 1990s when he established his own chimp research center deep in the heart of the Cajun bayous, Povinelli, then an impressive young anthropologist who had recently earned his doctoral degree from Yale and who had cut his teeth on his school’s undergraduate debating team, had become irritated by what he believed was a misguided agenda among comparative psychologists, one in which genuine differences between human beings and other animals were being swept under the rug while researchers instead focused on “narrowing the gap” between our minds. “If we are to make progress toward understanding how humans and chimpanzees can resemble each other so closely in behavior,” Povinelli once wrote in his characteristically strident style, “and yet differ so dramatically in psychological functioning, we need to abandon the visual rhetoric of
National Geographic
documentaries.”
²⁶
In other words, although anthropomorphizing other animals was increasingly in vogue, and the public had largely grown to distrust scientists who believed humans were “special,” this reluctance to focus on differences rather than similarities between humans and other animals wasn’t doing us any favors in terms of understanding human nature.

One of the major offenses Povinelli sought to expose was the poetic license that many researchers were taking in interpreting animal behavior in the wild. And contrary to what investigators such as Fouts would have us believe, he pointed out, chimpanzees are not merely hairy, watered-down little humans. Povinelli reasoned that of course a chimp’s behavior is similar to our own, because we do in fact share a relatively recent common ancestor with them, as well as 98.4 percent of our DNA. But because we can’t help but see and interpret their behaviors through the lens of our own theory of mind (a cognitive trait that Povinelli believes evolved
after
this common ancestor split into two separate ancestral lines, one leading to our own species and the other to modern chimps), we may be seeing more than is actually there. Perhaps we’re simply reading into their behaviors by projecting our own psychology onto theirs.

Now, determining whether a chimp has thoughts about others’ thoughts is a rather tricky research question. But Povinelli had some ingenious ways of going about it. For example, in a famous series of experiments published as a monograph titled
What Young Chimpanzees Know about Seeing
(1996), Povinelli trained his group of seven apes to come into the lab one at a time, reach their arms through a hole in a Plexiglas partition, and beg for a food reward from one of two human experimenters. There were two holes, one in front of each of the two experimenters, respectively. If the chimps reached out to person A, then person A would hand them the treat. If the chimps reached out to person B, person B would give it to them instead. But the chimps got only one choice between these two experimenters before the next trial began and the chimp next in line made its own selection.

After the animals got the gist of this simple game, the real experiment began. The rules remained the same—again, reach through one of the holes to get that person to fetch your treat—but now when the chimp entered the lab, it saw one of the experimenters wearing a blindfold, or with her back turned, her eyes closed, or even wearing a bucket over her head. The other experimenter, meanwhile, had her eyes wide open and was watching the chimp attentively.

If you’re thinking like an experimental psychologist, then the purpose of the study should at this point be jumping out at you. Povinelli hypothesized that if chimpanzees have a theory of mind, well then they should quite clearly pick the person who can see them over the one who can’t. After all, picking the unsighted experimenter would leave the chimp without its prize because—being unable to see the chimp’s gesture toward her—this person can’t possibly
know
she has been chosen. The point is that to avoid making the wrong choice, the animal must take the perspective of the person, or at least attribute the mental state of “not seeing” to her.

Povinelli and his coauthor, Timothy Eddy, surprised almost everyone when they found that the chimps failed to show a preference between the two experimenters.
²⁷
By contrast, in a similar game, even two-year-old children showed a clear preference for the sighted person. Other cleverly designed studies followed, by both Povinelli and others, all presumably showing that, contrary to what we had been led to believe by the “visual rhetoric” of those Goodall-esque documentaries, chimps aren’t entirely like us after all; in particular, they lack a theory of mind and fail to reason about what others see, know, feel, believe, or intend.

These studies, along with Povinelli’s persuasive arguments for human uniqueness, convinced many at the time, but they certainly didn’t convince all. In fact, soon the tables turned again, and just like those he had criticized before, Povinelli now found himself to be the subject of scathing criticism. He was excoriated by the “Darwinian continuity theorists” for his contrived laboratory approaches to such a complex question—ones in which chimps were asked to reason about the mental states of humans rather than those of their own kind. And that’s not even to mention, others pointed out, the fact that Povinelli’s Louisiana apes were raised in concrete-and-steel cages and therefore could hardly be regarded as the best and brightest of their species—or even representative of their species, for that matter, because their cognitive potential had probably been stultified under such poor, restricted conditions. Making a comparison to the “biological ignorance” likely to be found in an average human group of stuffy, Western suburbanites whose knowledge of the natural world hadn’t blossomed under the jungle canopy (their natural capacity to acquire such a biological understanding instead being starved by interminable deserts of strip malls, gabled houses, and Starbucks), German primatologist Christophe Boesch surmises in the
Journal of Comparative Psychology,