The following is an edited excerpt from The Belief Instinct, which will be published Feb. 7.

The scientific jury is still out on whether our species is unique among social mammals in being able to conceptualize mental states—other species, such as chimps, dogs, scrub jays and dolphins, may have some modest capacity in this regard. But there’s absolutely no question that we’re much better at it than the rest of the animal kingdom. We are natural psychologists, exquisitely attuned to the unseen psychological world. Reasoning about abstract mental states is as much a trademark of our species as walking upright on two legs, learning a language, and raising our offspring into their teens.

There is a scientific term for this way of thinking—”theory of mind.” It’s perhaps easiest to grasp the concept when considering how we struggle to make sense of someone else’s bizarre or unexpected behavior. If you’ve ever seen an unfortunate woman at the grocery store wearing a midriff-revealing top and packed into a pair of lavender tights like meat in a sausage wrapper, or a follicularly challenged man with a hairpiece two shades off and three centimeters adrift, and asked yourself what on Earth those people were thinking when they looked in the mirror before leaving the house, this is a good sign that your theory of mind (not to mention your fashion sense) is in working order. When others violate our expectations for normalcy or stump us with surprising behaviors, our tendency to mind-read goes into overdrive. We literally “theorize” about the minds that are causing ostensible behavior.

The evolutionary significance of this mind-reading system hinges on one gigantic question: Is this psychological capacity—this theory of mind, this seeing souls glimmering beneath the skin, spirits twinkling behind orbiting eyes, thoughts in the flurry of movement—is this the “one big thing” that could help us finally understand what it means to be human? Could it tell us something about how we find meaning in the universe?

As a human being, you’re prone to overextending your theory of mind to categories for which it doesn’t properly belong. Many people remember fondly the classic film Le Ballon Rouge (“The Red Balloon,” 1956) by French filmmaker Albert Lamorisse, in which a sensitive schoolboy—in reality Lamorisse’s own 5-year-old son, Pascal—is befriended by a good-natured, cherry-red helium balloon. Absent dialogue, the camera follows the joyful two, boy and balloon, through the somber, working-class streets of the Ménilmontant neighborhood of Paris, the glossy red balloon contrasting sharply with the bleak old-Europe atmosphere while adults, oblivious to the presence of an inanimate object that has apparently been ensouled by an intelligent gas, are largely indifferent, even hostile, to the pair. Eventually, a mob of cruel children corners the boy and begins pelting the “kindhearted” balloon with stones, ultimately popping it.

The plot of Le Ballon Rouge exemplifies how our evolved brains have become hypersocial filters, such that our theory of mind is applied not only to the mental innards of other people and animals, but also, in error, to categories that haven’t any mental innards at all, such as ebullient skins of elastic stretched by an inert gas. If it weren’t for our theory of mind, we couldn’t follow the premise of the movie, let alone enjoy Lamorisse’s particular oeuvre of magical realism. When the balloon hovers outside Pascal’s flat after his grandmother tries to get rid of it, we perceive a charismatic personality that “wants” to be with the boy and is “trying” to leverage itself against the window panes; it “sees” Pascal and “knows” he’s inside. Our theory of mind is so effortlessly applied under such conditions that it’s impossible to see the scene any other way. In fact, part of what makes the movie so effective is that the young boy in the lead role genuinely believed that the balloon was alive. “The Red Balloon was my friend,” recalled a much older Pascal Lamorisse in a 2007 interview. “When you were filming it, did you really feel that way?” asked the reporter. “Yes, yes, he was a real character with a spirit of his own.”

As a direct consequence of the evolution of the human social brain, and owing to the importance of our theory-of-mind skills in that process, we sometimes can’t help but see intentions, desires, and beliefs in things that haven’t even a smidgeon of a neural system. In particular, when inanimate objects do unexpected things, we sometimes reason about them just as we do for oddly behaving—or misbehaving—people. More than a few of us have kicked our broken-down vehicles in the sides and verbally abused our incompetent computers. Most of us stop short of actually believing these objects possess mental states—indeed, we would likely be hauled away to an asylum if we genuinely believed that they held malicious intent—but our emotions and behaviors toward such objects seem to betray our primitive, unconscious thinking: we act as though they’re morally culpable for their actions.

Some developmental psychologists even believe that this cognitive bias to see intentions in inanimate objects—and thus formulate a very basic theory of mind—can be found in babies just a few months out of the womb. For example, Hungarian psychologists György Gergely and Gergely Csibra from the Central European University in Budapest have shown that babies, on the basis of their staring response, act surprised when a dot on a computer screen continues to butt up against an empty space on the screen after a computerized barrier blocking its path has been deleted. It’s as if the baby is trying to figure out why the dot is acting as though it “thinks” the barrier is still there. By contrast, the infants are not especially interested—that is, they don’t stare in surprise—when the dot stops in front of the block, or when the dot continues along its path in the absence of the barrier.

The most famous example of this cognitive phenomenon of seeing minds in nonliving objects, however, is a 1944 American Journal of Psychology study by Austrian researchers Fritz Heider and Mary-Ann Simmel. The scientists put together a simplistic animated film depicting three moving, black-and-white figures: a large triangle, a small triangle, and a small circle. Participants watched the figures moving about on the screen for a while and then were asked to describe what they had just seen. Most fell back on a human social behavioral narrative—for example, seeing the large triangle as “bullying” the “timid” smaller triangle, both of “whom” were “seeking” the “affections” of the “female” circle.

So it would appear that having a theory of mind was so useful for our ancestors in explaining and predicting other people’s behaviors that it has completely flooded our evolved social brains. As a result, today we overshoot our mental-state attributions to things that are, in reality, completely mindless. And all of this leads us, rather inevitably, to a very important question: What if I were to tell you that God’s mental states, too, were all in your mind? That God, like a tiny speck floating at the edge of your cornea producing the image of a hazy, out-of-reach orb accompanying your every turn, was in fact a psychological illusion, a sort of evolved blemish etched onto the core cognitive substrate of your brain? It may feel as if there is something grander out there … watching, knowing, caring. Perhaps even judging. But, in fact, that’s just your overactive theory of mind. In reality, there is only the air you breathe.

After all, once we scrub away all the theological bric-a-brac and pluck the exotic cross-cultural plumage of religious beliefs from all over the world, once we get under God’s skin, isn’t He really just another mind—one with emotions, beliefs, knowledge, understanding, and, perhaps above all else, intentions? Aren’t theologians really just playing the role of God’s translators, and isn’t every holy book ever written a detailed psychoanalysis of God? That strangely sticky sense that God “willfully” created us as individuals, “wants” us to behave in particular ways, “observes” and “knows” about our otherwise private actions, “communicates” messages to us in code through natural events, and “intends” to meet us after we die would have also been felt, in some form, by our Pleistocene ancestors.

Consider, briefly, the implications of seeing God this way, as a sort of scratch on our psychological lenses rather than the enigmatic figure out there in the heavenly world that most people believe Him to be. Subjectively, God would still be present in our lives. (For some people, rather annoyingly so.) He would continue to suffuse our experiences with an elusive meaning and give the sense that the universe is communicating with us in various ways. But this notion of God as an illusion is a radical and, some would say, even dangerous idea because it raises important questions about whether God is an autonomous, independent agent that lives outside human brain cells, or instead a phantom cast out upon the world by our species’ own peculiarly evolved theory of mind. Since the human brain, like any physical organ, is a product of evolution, and since natural selection works without recourse to intelligent forethought, this mental apparatus of ours evolved to think about God quite without need of the latter’s consultation, let alone His being real.

Then again, one can never rule out the possibility that God microengineered the evolution of the human brain so that we’ve come to see Him more clearly, a sort of divine LASIK procedure, or scraping off the bestial glare that clouds the minds of other animals.

Either way, this cognitive capacity, this theory of mind, has baked itself into our heads when it comes to our pondering of life’s big questions. Unlike any science-literate generation that has come before, we now possess the intellectual tools to observe our own minds at work and to understand how God came to be there. And we alone are poised to ask, “Has our species’ unique cognitive evolution duped us into believing in this, the grandest mind of all?”

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