The Case Against Reality: Why Evolution Hid the Truth from Our Eyes

by Donald D. Hoffman

The purpose of a desktop interface is not to show you the “truth” of the computer—where “truth,” in this metaphor, refers to circuits, voltages, and layers of software. Rather, the purpose of an interface is to hide the “truth” and to show simple graphics that help you perform useful tasks such as crafting emails and editing photos. If you had to toggle voltages to craft an email, your friends would never hear from you.

That is what evolution has done. It has endowed us with senses that hide the truth and display the simple icons we need to survive long enough to raise offspring.

But despite all this data, we still have no plausible story about how brain activity might generate a conscious experience.

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molecules. . . . ‘You’re nothing but a pack of neurons.’

Explaining experiments like these earned Roger Sperry a share of the Nobel Prize for Physiology and Medicine in 1981.

To the untutored intuition, it seems unlikely that consciousness can be split with a scalpel. What could it mean to split my feelings, my knowledge, my emotions, my beliefs, my personality, my very self? Most of us would dismiss the idea as ludicrous. But to Sperry, after years of careful experiments, the evidence was clear: “Actually the evidence as we see it favors the view that the minor hemisphere is very conscious indeed, and further that both the separated left and the right hemispheres may be conscious simultaneously in different and even conflicting mental experiences that run along in parallel.”

The evidence for this conclusion has continued to mount. In one patient, the career goals of the two hemispheres differed: the left hemisphere said that it wanted to be a “draftsman,” and the right hemisphere, using the left hand to assemble scrabble letters, wrote that it wished to “automobile race.”8 In another, the left hemisphere used the right hand to button a shirt, while the right hemisphere used the left hand to promptly unbutton it; the right hand lit a cigarette and the left put it out. Two persons, with distinct likes and dislikes, appear to reside—and sometimes quarrel—side by side, inside one skull.

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The path from correlation to causation, to be sure, is fraught with pitfalls: if a crowd forms at a train platform, then often a train soon arrives.16 But crowds don’t impel trains to roll in. Something else—a train schedule—creates the correlation between crowds and trains.

NCCs are important for theory, and also for practice. Arachnophobia, an excessive fear of spiders, is correlated with activity in the amygdala. Triggering this fear and its NCC in the amygdala allows both to be erased. Merel Kindt, a psychotherapist in the Netherlands, cures arachnophobia by asking the arachnophobe first to touch a live tarantula, thus activating the phobia and its NCC. She then asks the patient to take a forty-milligram pill of propranolol, a ß-adrenergic blocker that disrupts the NCC from being stored back into memory. When the patient returns the next day, the phobia is gone.20 This therapy holds promise for other phobias, and for posttraumatic stress disorder.

Then later, Denny can trigger its happy NCC using fiber optics that flash into its brain a colored light that activates the protein. Even if the mouse sits in a frightful place—hard, bright, nowhere to take cover—it feels a halcyon space, until the fiber optics are turned off. Then it freezes in fear. Turn the light back on, and once again it happily grooms and explores.

These are impressive applications of NCCs. Equally impressive is our utter failure to understand the relation between NCCs and consciousness. We have no scientific theories that explain how brain activity—or computer activity, or any other kind of physical activity—could cause, or be, or somehow give rise to, conscious experience. We don’t have even one idea that’s remotely plausible.

What do we want in a scientific theory of consciousness? Consider the case of tasting basil versus hearing a siren. For a theory that proposes that brain activity causes conscious experiences, we want mathematical laws or principles that state precisely which brain activities cause the conscious experience of tasting basil, precisely why this activity does not cause the experience of, say, hearing a siren, and precisely how this activity must change to transform the experience from tasting basil to, say, tasting rosemary. These laws or principles must apply across species, or else explain precisely why different species require different laws. No such laws, indeed no plausible ideas, have ever been proposed.

We have scientific laws that predict black holes, the dynamics of quarks, and the evolution of the universe. Yet we have no clue how to formulate laws, principles, or mechanisms that predict our quotidian experiences of tasting herbs and hearing street noise.

Or perhaps we were short-changed by evolution, and lack the concepts needed to understand the relationship between brains and consciousness. Cats can’t do calculus and monkeys can’t do quantum theory, so why assume that Homo sapiens can demystify consciousness? Perhaps we don’t need more data. Perhaps what we need is a mutation that lets us understand the data we have.

Noam Chomsky dismisses arguments from evolution about limits to our cognitive capacities. But he insists nonetheless that we must recognize “the scope and limits of human understanding” and that “some differently structured intelligence might regard human mysteries as simple problems and wonder that we cannot find the answers, much as we can observe the inability of rats to run prime number mazes because of the very design of their cognitive nature.”

False beliefs, rather than innate limits, can stump our efforts to solve puzzles. Examples of this are standard fare in textbooks on cognitive science. In one example, people are given a candle, a box of thumbtacks, and a book of matches. They’re asked to fasten the candle to a wall so that, when lit, its wax can’t drip on the floor. Most people fail. They tacitly assume that the box must do one thing—hold thumbtacks. They don’t think to dump the tacks out of the box, to use the tacks to fasten the box to the wall, and to put the candle in the box. To solve the puzzle, they must challenge a false assumption. What false assumption bedevils our efforts to unravel the relation between brain and consciousness? I propose it is this: we see reality as it is

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prove that if our perceptions were shaped by natural selection then they almost surely evolved to hide reality. They just report fitness.

Galileo was forced to recant, and sentenced to house arrest for the remainder of his life. It wasn’t until 1992 that the Church acknowledged its error.

But evolution disagrees. We will see in chapter four that evolution by natural selection entails a counterintuitive theorem: the probability is zero that we see reality as it is

“Moderation,” he wrote, “is a fatal thing. . . . Nothing succeeds like excess.”

Sharbat Gula

Sometimes the lie is cynical and exploitative. Hammer orchids, of the genus Drakaea in Western Australia, peddle sex to thynnid wasps.9 The female wasp, when in the mood, climbs a blade of grass and rubs her legs to broadcast a scent appealing to males. A charmed male tracks her scent and flies a snaking pattern upwind until he finds her. He embraces her, whisks her up to the meter-high club, then down to his prearranged pad, which caters a gourmet banquet of beetle larvae. There she lays her eggs and dies. The average flower next door has no chance to seduce a male thynnid. But the genes of the hammer orchid have given it a celebrity makeover: a green and slender stem with the ambience of grass; dangling from its top, a labellum with the shapely curves, alluring color, velvety texture, and enticing scent of a female thynnid. An entranced male tries to whisk off with the labellum, but learns that this would-be mate will not cooperate. He eventually flies off in frustration, bearing pollen daubed on him surreptitiously during his deflating ordeal. When he tries his luck with another fake mate, he pollinates it. In this charade, Drakaea genes get fitness; the wasp just gets used.

Human biology dictates that each woman must invest heavily in each child. But it gives each man a choice. Some men invest little. But many choose to invest heavily, to provide food and protection for their mate and children. In no other species of primates do males regularly provide food; females fend for themselves.

But genes don’t stop at masculine faces. They choreograph a woman’s preference for masculine gaits, bodies, odors, voices, and personalities.29 Women in the low fertility phase feel more commitment to their partner, but during the high fertility phase they are more prone to cheat, to fantasize about cheating, to dress attractively, and to meet and flirt with new men.30 If, however, a woman’s partner is attractive, or if his MHC genes, which code for the immune system, complement hers and incline their children toward immune health, then her wandering eye is less pronounced—again a clever strategy by genes to play the odds for a greater fitness payoff.31 For the most part, these machinations of genes fly under the radar of conscious experience and foster, but do not force, a choice of action.

Some women are attracted to “bad boys,” men who are “fickle, frivolous, opportunistic, hardheaded, handsome, confident and conceited.”39 These women prefer larger pupils in the eyes of men.

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Evolutionary psychology reveals that our perception of beauty is an estimate of reproductive potential. This does not entail that we have sex only to procreate. Exaptation, in which a trait evolved for one function can co-opt a new function, is commonplace in nature. We use sex to procreate, but also to bond, play, heal, and enjoy pleasure.

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Crick said in his letter that the thing-in-itself—the tomato-in-itself or the neuron-in-itself—“is essentially unknowable.” But most of us believe otherwise. We believe, for instance, that the tomato-in-itself is, like our experience, red and tomato-shaped and a meter away. We believe that experience accurately depicts the thing-in-itself.

Indeed,

I soon learned that Marr had leukemia. He died fourteen months later, in November of 1980, at the age of thirty-five. But those fourteen months exceeded my expectations. Marr inspired in person as he did in print. He was the center of gravity for a community of eager students and brilliant colleagues. Discussions were lively, multidisciplinary, and game-changing.

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“Our minds evolved by natural selection to solve problems that were life-and-death matters to our ancestors, not to commune with correctness.”

This observation is central. Our minds were shaped by natural selection to solve life-and-death problems. Full stop. They were not shaped to commune with correctness. Whether our beliefs and perceptions happen to be true is a question that requires careful study.

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Fitness depends on payoffs and on how many players adopt each strategy. If everyone is a dove, then it’s more fit to be a hawk. If everyone is a hawk, then it’s more fit to be a dove. The force of natural selection depends on the frequency of each strategy.

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That revolutionized view leaves in its wake an evolutionary biology that is itself transformed. Still recognizable, after the bath in Darwin’s acid, are the landmarks of universal Darwinism: variation, selection, and heredity. But gone from objective reality are physical objects in spacetime, including those central to biology: DNA, RNA, chromosomes, organisms, and resources. This doesn’t entail solipsism. Something is there in objective reality, and we humans experience its import for our fitness in terms of DNA, RNA, chromosomes, organisms, and resources. But the FBT Theorem tells us that, whatever that something is, it is almost surely not DNA, RNA, chromosomes, organisms, or resources. It tells us that there is good reason to believe that the things that we perceive, such as DNA and RNA, don’t exist independent of our minds. The reason is that the structures of fitness payoffs, which shape what we perceive, differ from the structures of objective reality with high probability. Again, this is no support for solipsism: there is an objective reality. But that reality is utterly unlike our perceptions of objects in space and time.

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But this emphasis on natural selection and adaptation raises a different objection, one spelled out by the psychologist Rainer Mausfeld: “the actual role of natural selection in the evolution of complex biological systems is far from obvious. . . . Evolutionary biology has, in more recent years, accumulated pervasive evidence that suggests that the vast majority of evolutionary change has rather little to do with natural selection.” Mausfeld worries that the arguments discussed here take natural selection “as an almost exclusive factor regulating evolutionary change.”

Of the ninety-two elements that occur in nature only six—carbon, hydrogen, nitrogen, oxygen, calcium, and phosphorus—compose 99 percent of the mass of organisms.

Let’s begin by digging deeper into an example from the preface. Suppose you’re crafting an email, and the icon for the file is blue, rectangular, and in the center of the desktop. Does this mean that the file itself is blue, rectangular, and in the center of your computer? Of course not. The color of the icon is not the true color of the file. The shape and location of the icon are not the true shape and location of the file. Indeed, the file has no color or shape; and the location of its bits in the computer is irrelevant to the placement of its icon on the desktop.