The Blank Slate
Page 32
Physical images such as photographs and paintings are devices that reflect light in patterns similar to those coming off real objects, thereby making the visual system respond as if it were really seeing those objects. Though people have long dreamed of illusions that completely fool the brain—Descartes’s evil demon, the philosopher’s thought experiment in which a person does not realize he is a brain in a vat, the science-fiction writer’s prophecy of perfect virtual reality like in The Matrix—in actuality the illusions foisted upon us by physical images are never more than partially effective. Our perceptual systems pick up on the imperfections of an image—the brush strokes, pixels, or frame—and our conceptual systems pick up on the fact that we are entertaining a hypothetical world that is separate from the real world. It’s not that people invariably distinguish fiction from reality: they can lose themselves in fiction, or misremember something they read in a novel as something they read in the newspapers or that happened to a friend, or mistakenly believe that a stylized portrayal of a time and place is an accurate portrayal. But all of us are capable of distinguishing fictitious worlds from real ones, as we see when a two-year-old pretends that a banana is a telephone for the fun of it but at the same time understands that a banana is not literally a telephone.40 Cognitive scientists believe that the ability to entertain propositions without necessarily believing them—to distinguish “John believes there is a Santa Claus” from “There is a Santa Claus”—is a fundamental ability of human cognition.41 Many believe that a breakdown of this ability underlies the thought disorder in the syndrome called schizophrenia.42
Finally, there are mental images, the visualizations of objects and scenes in the mind’s eye. The psychologist Stephen Kosslyn has shown that the brain is equipped with a system capable of reactivating and manipulating memories of perceptual experience, a bit like Photoshop with its tools for assembling, rotating, and coloring images.43 Like language, imagery may be used as a slave system—a “visuospatial sketchpad”—by the central executive of the brain, making it a valuable form of mental representation. We use mental imagery, for example, when we visualize how a chair might fit in a living room or whether a sweater would look good on a relative. Imagery is also an invaluable tool to novelists, who imagine scenes before describing them in words, and to scientists, who rotate molecules or play out forces and motions in their imagination.
Though mental images allow our experiences (including our experience of media images) to affect our thoughts and attitudes long after the original objects have gone, it is a mistake to think that raw images are downloaded into our minds and then constitute our mental lives. Images are not stored in the mind like snapshots in a shoebox; if they were, how could you ever find the one you want? Rather, they are labeled and linked to a vast database of knowledge, which allows them to be evaluated and interpreted in terms of what they stand for.44 Chess masters, for example, are famous for their ability to remember games in progress, but their mental images of the board are not raw photographs. Rather, they are saturated with abstract information about the game, such as which piece is threatening which other one and which clusters of pieces form viable defenses. We know this because when a chessboard is sprinkled with pieces at random, chess masters are no better at remembering the arrangement than amateurs are.45 When images represent real people, not just chessmen, there are even more possibilities for organizing and annotating them with information about people’s goals and motives—for example, whether the person in an image is sincere or just acting.
The reason that images cannot constitute the contents of our thoughts is that images, like words, are inherently ambiguous. An image of Lassie could stand for Lassie, collies, dogs, animals, television stars, or family values. Some other, more abstract form of information must pick out the concept that an image is taken to exemplify. Or consider the sentence Yesterday my uncle fired his lawyer (an example suggested by Dan Dennett). When understanding the sentence, Brad might visualize his own ordeals of the day before and glimpse the “uncle” slot in a family tree, then picture courthouse steps and an angry man. Irene might have no image for “ yesterday” but might visualize her uncle Bob’s face, a slamming door, and a power-suited woman. Yet despite these very different image sequences, both people have understood the sentence in the same way, as we could see by questioning them or asking them to paraphrase the sentence. “Imagery couldn’t be the key to comprehension,” Dennett points out, “because you can’t draw a picture of an uncle; or of yesterday, or firing, or a lawyer. Uncles, unlike clowns and firemen, don’t look different in any characteristic way that can be visually represented, and yesterdays don’t look like anything at all.”46
Since images are interpreted in the context of a deeper understanding of people and their relationships, the “crisis of representation,” with its paranoia about the manipulation of our mind by media images, is overblown. People are not helplessly programmed with images; they can evaluate and interpret what they see using everything else they know, such as the credibility and motives of the source.
The postmodernist equating of images with thoughts has not only made a hash of several scholarly disciplines but has laid waste to the world of contemporary art. If images are the disease, the reasoning goes, then art is the cure. Artists can neutralize the power of media images by distorting them or reproducing them in odd contexts (like the ad parodies in Mad magazine or on Saturday Night Live, only not funny). Anyone familiar with contemporary art has seen the countless works in which stereotypes of women, minorities, or gay people are “reinforced, parodied, or actively contested.” A prototypical example is a 1994 exhibit at the Whitney Museum in New York called “Black Male: Representations of Masculinity in Contemporary Art.” It aimed to take apart the way that African American men are culturally constructed in demonizing and marginalizing visual stereotypes such as the sex symbol, the athlete, the Sambo, and the photograph in a Wanted poster. According to the catalogue essay, “The real struggle is over the power to control images.” The art critic Adam Gopnik (whose mother and sister are cognitive scientists) called attention to the simplistic theory of cognition behind this tedious formula:
The show is intended to be socially therapeutic: its aim is to make you face the socially constructed images of black men, so that by confronting them—or, rather, seeing artists confront them on your behalf—you can make them go away. The trouble is that the entire enterprise of “disassembling social images” rests on an ambiguity in the way we use the word “image.” Mental images are not really images at all, but instead consist of complicated opinions, positions, doubts, and passionately held convictions, rooted in experience and amendable by argument, by more experience, or by coercion. Our mental images of black men, white judges, the press, and so on do not take the form of pictures of the kind that you can hang up (or “deconstruct”) on a museum wall…. Hitler did not hate Jews because there were pictures of swarthy Semites with big noses imprinted on his cerebellum; racism does not exist in America because the picture of O.J. Simpson on the cover of Time is too dark. The view that visual clichés shape beliefs is both too pessimistic, in that it supposes that people are helplessly imprisoned by received stereotypes, and too optimistic, in that it supposes that if you could change the images you could change the beliefs.47
Recognizing that we are equipped with sophisticated faculties that keep us in touch with reality does not entail ignoring the ways in which our faculties can be turned against us. People lie, sometimes baldly, sometimes through insinuation and presupposition (as in the question “When did you stop beating your wife?”). People disseminate disinformation about ethnic groups, not just pejorative stereotypes but tales of exploitation and perfidy that serve to stoke moralistic outrage against them. People try to manipulate social realities like status (which exist in the mind of the beholder) to make themselves look good or to sell products.
But we can best protect ourselves against such manipulation by pinpointing the vulnerabilities of o
ur faculties of categorization, language, and imagery, not by denying their complexity. The view that humans are passive receptacles of stereotypes, words, and images is condescending to ordinary people and gives unearned importance to the pretensions of cultural and academic elites. And exotic pronouncements about the limitations of our faculties, such as that there is nothing outside the text or that we inhabit a world of images rather than a real world, make it impossible even to identify lies and misrepresentations, let alone to understand how they are promulgated.
Chapter 13
Out of Our Depths
A man has got to know his limitations.
—Clint Eastwood in Magnum Force
MOST PEOPLE ARE familiar with the idea that some of our ordeals come from a mismatch between the source of our passions in evolutionary history and the goals we set for ourselves today. People gorge themselves in anticipation of a famine that never comes, engage in dangerous liaisons that conceive babies they don’t want, and rev up their bodies in response to stressors from which they cannot run away.
What is true for the emotions may also be true for the intellect. Some of our perplexities may come from a mismatch between the purposes for which our cognitive faculties evolved and the purposes to which we put them today. This is obvious enough when it comes to raw data processing. People do not try to multiply six-digit numbers in their heads or remember the phone number of everyone they meet, because they know their minds were not designed for the job. But it is not as obvious when it comes to the way we conceptualize the world. Our minds keep us in touch with aspects of reality—such as objects, animals, and people—that our ancestors dealt with for millions of years. But as science and technology open up new and hidden worlds, our untutored intuitions may find themselves at sea.
What are these intuitions? Many cognitive scientists believe that human reasoning is not accomplished by a single, general-purpose computer in the head. The world is a heterogeneous place, and we are equipped with different kinds of intuitions and logics, each appropriate to one department of reality. These ways of knowing have been called systems, modules, stances, faculties, mental organs, multiple intelligences, and reasoning engines.1 They emerge early in life, are present in every normal person, and appear to be computed in partly distinct sets of networks in the brain. They may be installed by different combinations of genes, or they may emerge when brain tissue self-organizes in response to different problems to be solved and different patterns in the sensory input. Most likely they develop by some combination of these forces.
What makes our reasoning faculties different from the departments in a university is that they are not just broad areas of knowledge, analyzed with whatever tools work best. Each faculty is based on a core intuition that was suitable for analyzing the world in which we evolved. Though cognitive scientists have not agreed on a Gray’s Anatomy of the mind, here is a tentative but defensible list of cognitive faculties and the core intuitions on which they are based:
• An intuitive physics, which we use to keep track of how objects fall, bounce, and bend. Its core intuition is the concept of the object, which occupies one place, exists for a continuous span of time, and follows laws of motion and force. These are not Newton’s laws but something closer to the medieval conception of impetus, an “oomph” that keeps an object in motion and gradually dissipates.2
• An intuitive version of biology or natural history, which we use to understand the living world. Its core intuition is that living things house a hidden essence that gives them their form and powers and drives their growth and bodily functions.3
• An intuitive engineering, which we use to make and understand tools and other artifacts. Its core intuition is that a tool is an object with a purpose—an object designed by a person to achieve a goal.4
• An intuitive psychology, which we use to understand other people. Its core intuition is that other people are not objects or machines but are animated by the invisible entity we call the mind or the soul. Minds contain beliefs and desires and are the immediate cause of behavior.
• A spatial sense, which we use to navigate the world and keep track of where things are. It is based on a dead reckoner, which updates coordinates of the body’s location as it moves and turns, and a network of mental maps. Each map is organized by a different reference frame: the eyes, the head, the body, or salient objects and places in the world.5
• A number sense, which we use to think about quantities and amounts. It is based on an ability to register exact quantities for small numbers of objects (one, two, and three) and to make rough relative estimates for larger numbers.6
• A sense of probability, which we use to reason about the likelihood of uncertain events. It is based on the ability to track the relative frequencies of events, that is, the proportion of events of some kind that turn out one way or the other.7
• An intuitive economics, which we use to exchange goods and favors. It is based on the concept of reciprocal exchange, in which one party confers a benefit on another and is entitled to an equivalent benefit in return.
• A mental database and logic, which we use to represent ideas and to infer new ideas from old ones. It is based on assertions about what’s what, what’s where, or who did what to whom, when, where, and why. The assertions are linked in a mind-wide web and can be recombined with logical and causal operators such as AND, OR, NOT, ALL, SOME, NECESSARY, POSSIBLE, and CAUSE.8
• Language, which we use to share the ideas from our mental logic. It is based on a mental dictionary of memorized words and a mental grammar of combinatorial rules. The rules organize vowels and consonants into words, words into bigger words and phrases, and phrases into sentences, in such a way that the meaning of the combination can be computed from the meanings of the parts and the way they are arranged.9
The mind also has components for which it is hard to tell where cognition leaves off and emotion begins. These include a system for assessing danger, coupled with the emotion called fear, a system for assessing contamination, coupled with the emotion called disgust, and a moral sense, which is complex enough to deserve a chapter of its own.
These ways of knowing and core intuitions are suitable for the lifestyle of small groups of illiterate, stateless people who live off the land, survive by their wits, and depend on what they can carry. Our ancestors left this lifestyle for a settled existence only a few millennia ago, too recently for evolution to have done much, if anything, to our brains. Conspicuous by their absence are faculties suited to the stunning new understanding of the world wrought by science and technology. For many domains of knowledge, the mind could not have evolved dedicated machinery, the brain and genome show no hints of specialization, and people show no spontaneous intuitive understanding either in the crib or afterward. They include modern physics, cosmology, genetics, evolution, neuroscience, embryology, economics, and mathematics.
It’s not just that we have to go to school or read books to learn these subjects. It’s that we have no mental tools to grasp them intuitively. We depend on analogies that press an old mental faculty into service, or on jerry-built mental contraptions that wire together bits and pieces of other faculties. Understanding in these domains is likely to be uneven, shallow, and contaminated by primitive intuitions. And that can shape debates in the border disputes in which science and technology make contact with everyday life. The point of this chapter is that together with all the moral, empirical, and political factors that go into these debates, we should add the cognitive factors: the way our minds naturally frame issues. Our own cognitive makeup is a missing piece of many puzzles, including education, bioethics, food safety, economics, and human understanding itself.
THE MOST OBVIOUS arena in which we confront native ways of thinking is the schoolhouse. Any theory of education must be based on a theory of human nature, and in the twentieth century that theory was often the Blank Slate or the Noble Savage.
Traditional education is based in large part on the Bla
nk Slate: children come to school empty and have knowledge deposited in them, to be reproduced later on tests. (Critics of traditional education call this the “savings and loan” model.) The Blank Slate also underlies the common philosophy that the early school-age years are an opportunity zone in which social values are shaped for life. Many schools today use the early grades to instill desirable attitudes toward the environment, gender, sexuality, and ethnic diversity.
Progressive educational practice, for its part, is based on the Noble Savage. As A. S. Neill wrote in his influential book Summerhill, “ A child is innately wise and realistic. If left to himself without adult suggestion of any kind, he will develop as far as he is capable of developing.”10 Neill and other progressive theorists of the 1960s and 1970s argued that schools should do away with examinations, grades, curricula, and even books. Though few schools went that far, the movement left a mark on educational practice. In the method of reading instruction known as Whole Language, children are not taught which letter goes with which sound but are immersed in a book-rich environment where reading skills are expected to blossom spontaneously.11 In the philosophy of mathematics instruction known as constructivism, children are not drilled with arithmetic tables but are enjoined to rediscover mathematical truths themselves by solving problems in groups.12 Both methods fare badly when students’ learning is assessed objectively, but advocates of the methods tend to disdain standardized testing.
An understanding of the mind as a complex system shaped by evolution runs against these philosophies. The alternative has emerged from the work of cognitive scientists such as Susan Carey, Howard Gardner, and David Geary.13 Education is neither writing on a blank slate nor allowing the child’s nobility to come into flower. Rather, education is a technology that tries to make up for what the human mind is innately bad at. Children don’t have to go to school to learn to walk, talk, recognize objects, or remember the personalities of their friends, even though these tasks are much harder than reading, adding, or remembering dates in history. They do have to go to school to learn written language, arithmetic, and science, because those bodies of knowledge and skill were invented too recently for any species-wide knack for them to have evolved.