Just Babies (3 page)

masturbation, homosexuality, sexual abstinence, polygamy, abortion, circumcision, corporal punishment, capital punishment, Islam, Christianity, Judaism, capitalism, democracy, flag burning, miniskirts, long hair, no hair, alcohol consumption, meat eating, medical inoculations, atheism, idol worship, divorce, widow marriage, arranged marriage, romantic love marriage, parents and children sleeping in the same bed, parents and children not sleeping in the same bed, women being allowed to work, women not being allowed to work.

But while the excerpts from Herodotus and Shweder illustrate diversity, they also hint at universals. Ethnographic reports often ignore what humans share, in part because of
the tendency of anthropologists to exaggerate how exotic other people are (something that the anthropologist Maurice Bloch has described as “professional malpractice”) and in part because, from an anthropological perspective, there isn’t anything interesting to say about universals; it would be like reading in a travel guide that the people you will encounter have noses, drink water, and age over time. It is all too obvious to be worth noting. By the same token, we take for granted that people everywhere have a natural disapproval toward actions such as lying, breaking a promise, and murder. Herodotus doesn’t talk about people who don’t care what you do with dead bodies; Shweder doesn’t describe people who are indifferent about incest. Such people don’t exist.

If you think of evolution solely in terms of “survival of
the fittest” or “nature red in tooth and claw,” then such universals cannot be part of our natures. Since Darwin, though, we’ve come to see that evolution is far more subtle than a Malthusian struggle for existence. We now understand how the amoral force of natural selection might have instilled within us some of the foundation for moral thought and moral action.

Actually,
one aspect of morality, kindness to kin, has long been a no-brainer from an evolutionary point of view. The purest case here is a parent and a child: one doesn’t have to do sophisticated evolutionary modeling to see that the genes of parents who care for their children are more likely to spread through the population than those of parents who abandon or eat their children.

There are other kinship bonds as well, though, such as between siblings and cousins, and while these might be weaker, the difference is of degree, not kind. The story goes that the evolutionary biologist J. B. S. Haldane was once asked if he would give his life to save his drowning brother and he responded that he wouldn’t—but he would happily do so for two brothers or eight cousins. Since he shared, on average, half of his genes with each brother and one-eighth of his genes with each cousin, this was the proper strategy from the genes’ perspective. Haldane was being clever when he answered by making reference to these calculations—few people are consciously motivated by an explicit desire to preserve their genes—but these are the sorts of calculations that explain our normal motivations and desires. It turns out, then, that there is no hard-and-fast difference,
as far as the genes are concerned, between an individual and its blood relatives. In this way, selfish genes can create altruistic animals, animals that love others just as they love themselves.

We are also capable of acting kindly and generously toward those who are not blood relatives. At first, the evolutionary origin of this might seem obvious: clearly, we thrive by working together—in hunting, gathering, child care, and so on—and our social sentiments make this coordination possible.
Adam Smith pointed this out long before Darwin: “All the members of human society stand in need of each others assistance, and are likewise exposed to mutual injuries. Where the necessary assistance is reciprocally afforded from love, from gratitude, from friendship, and esteem, the society flourishes and is happy.” And so it is to everyone’s benefit to care about those around us.

But there is a wrinkle here; for society to flourish in this way, individuals have to refrain from taking advantage of others. A bad actor in a community of good people is the snake in the garden; it’s what the evolutionary biologist Richard Dawkins calls
“subversion from within.” Such a snake would do best of all, reaping the benefits of cooperation without paying the costs. Now, it’s true that the world as a whole would be worse off if the demonic genes proliferated, but this is the problem, not the solution—natural selection is insensitive to considerations about “the world as a whole.” We need to explain what kept demonic genes from taking over the population, leaving us with a world of psychopaths.

Darwin’s theory was that cooperative traits could prevail if societies containing individuals who worked together peacefully would tend to defeat other societies with less cooperative members—in other words, natural selection operating at the group, rather than individual, level. Writing of a hypothetical conflict between two imaginary tribes, Darwin wrote: “If the one tribe included … courageous, sympathetic and faithful members who were always ready to warn each other of danger, to aid and defend each other, this tribe would without doubt succeed best and conquer the other.” An alternative theory, more consistent with individual-level natural selection,
is that the good guys might punish the bad guys. That is, even without such conflict between groups, altruism could evolve if individuals were drawn to reward and interact with kind individuals and to punish—or at least shun—cheaters, thieves, thugs, free riders, and the like.

Other moral universals are harder to explain from an evolutionary perspective. Why are we so obsessed with the morality of sex? Why are we so quick to make moral distinctions on the basis of superficial physical features such as skin color? And how can we explain the emergence of moral notions such as equal rights for all? These are the topics of later chapters.

W
E SHOULD
take seriously, then, the idea that we possess an innate and universal morality. But we can’t know if this is true until we study the minds of babies.

Such research is hard; it is notoriously difficult to know
what is going on inside of a baby’s head. When my sons were babies, I would stare at them and wonder what, precisely, stared back. They were like my dog, only more fascinating. (Now they are teenagers, wonderful in many ways, but a lot less professionally interesting—I know what it’s like to be a teenager.) The developmental psychologist John Flavell once said that he would give up all his degrees and honors for just
five minutes inside the head of a two-year-old. I would give up a month of my life for those five minutes—and I’d give up six months for five minutes as an infant.

Part of the problem is that we don’t remember. The comedian Louis C.K. once compared a baby’s brain to an Etch A Sketch that you shake at the end of every day. Memories don’t stick; even young children don’t remember their babyhood.
The psychologist Charles Fernyhough describes asking his three-year-old daughter what it was like to be a baby. Trying to be helpful, she says: “You know what?… When I were a little baby, it was very sunny.”

Babies are even harder to study than rats and pigeons, which can at least run mazes or peck at levers. When my colleague and collaborator Karen Wynn is giving a public talk about conducting research with baby subjects, she puts up a picture of a slug for comparison.

You might think that psychologists scan babies’ brains, and, indeed, some researchers have made a promising start at this. But the brain-imaging methods designed for use with adults often are not suitable for babies because they are too dangerous or because the subjects must remain awake but still for a long period of time. Certain special
techniques, such as near-infrared spectroscopy, can be more easily used with babies, and might lead to important discoveries in the future. But at this point, the data they yield—about changes in blood oxygenation in parts of the brain—tell us little about the specifics of mental life. If you want to know
where
in the baby’s brain some cognitive process is taking place, these methods are the cat’s pajamas. But they are typically too insensitive to answer more precise questions about how babies think and what they know.

Fortunately, we have better methods. In the 1980s, psychologists began making use of one of the few behaviors that young babies can control: the movement of their eyes. These really are windows into the baby’s soul. How long babies stare at an object or a person—their “looking time”—can tell you a lot about their understanding.

One specific looking-time method is
habituation.
Like adults, if babies see the same thing over and over again, they’ll get bored and look away. Boredom—or “habituation”—is a response to sameness, so this method reveals what babies see as similar and as different. Suppose you were interested in whether babies can tell dogs from cats. Show them pictures of cats over and over again, until they get bored with cats. Then show them a picture of a dog. If they perk up, they can detect a difference; if they are still bored, then they can’t—for them, cat, cat, dog is the same as cat, cat, cat.

More generally, looking-time methods can help assess what someone finds to be new, interesting, or unexpected. Such methods are particularly well suited for babies.
The psychologist Alison Gopnik points out that adult attention
can be captured by external events—we will instinctively turn if someone calls our name, say—but we usually have control over what to attend to. By sheer will, we can choose to think about our left foot, visualize what we had for breakfast, and so on. But babies are largely at the mercy of the environment. The part of the brain responsible for inhibition and control, the prefrontal cortex, is among the last to develop. Gopnik compares baby consciousness to that of an adult dumped into the middle of a foreign city, totally overwhelmed, constantly turning to see new things, struggling to make sense of it all. Things are even worse for a baby, actually, because even the most stressed-out adult can choose to think of something else: we can look forward to getting back to the hotel; imagine how we would describe our trip to friends; fantasize, daydream, or pray. The baby just
is
, trapped in the here and now. No wonder babies are often so fussy. Luckily for researchers, their lack of internal control means that they are vulnerable to our methods.

Looking-time studies are difficult to construct, in part because one has to be careful to make sure that babies are responding to the right thing. For example, many studies find that babies distinguish two objects from three objects. If you bore the babies by showing them a series of pictures of two objects—two dogs, two chairs, two shoes, et cetera—and then show them a picture of three objects, they will look longer, suggesting that they can tell the difference between two and three. But a skeptic will point out that two objects typically take up less space than three, so perhaps babies are responding to the space that the objects
fill up—less versus more. One can try to address this by contrasting two bigger objects and three smaller objects, so that they fill up the same overall space, but the skeptic can then worry that babies are responding, not to the number of objects, but to big objects versus small objects. It turns out to be exquisitely complicated to design a study that isolates just the relevant variable—but it can be done.

The development of looking-time methods set off a revolution in how we think about the minds of babies. The first studies to use this method focused on early knowledge of physical objects—a baby’s “naive physics.” Psychologists showed babies magic tricks, events that seemed to violate some law of the universe: you remove the supports from beneath a block and it floats in midair, unsupported; an object disappears and then reappears in another location; a box is placed behind a screen, and the screen falls backward into empty space. If babies expect the world to work in accordance with the principles of physics, they should find these outcomes surprising. And their looking times show that they do—babies look longer at such scenes than at scenes that are identical in all regards except that they don’t violate physical laws. A vast body of research now suggests that—contrary to what legions of psychology undergraduates were taught for decades—babies think of objects largely as adults do, as connected masses that move as units, that are solid and subject to gravity, and that move in continuous paths through space and time.

In a classic study, Karen Wynn found that
babies can also do rudimentary math with objects. The demonstration
is simple. Show a baby an empty stage. Raise a screen in the middle of the stage. Put a Mickey Mouse doll behind the screen. Then put another Mickey Mouse doll behind the screen. Now drop the screen. Adults expect two dolls, and so do five-month-olds; if the screen drops to reveal one or three dolls, the babies look longer than they do if the screen drops to reveal two.

Experimenters have also used these methods to explore babies’ expectations about people—their “naive psychology,” as opposed to their
“naive physics.” We’ve long known that babies respond in a special way to other people. They are drawn to them.
They like the sound of human voices, particularly those they are familiar with; they like the look of human faces. And they are disturbed when interactions don’t go the way they expect. Here’s
how to freak out a baby: sit across from the baby, engage with him or her, and then suddenly become still. If this goes on for more than a few seconds, with you looking all corpselike, the baby will become upset.
In one study, two-month-olds were seated across from a TV screen displaying their mother. When the mother interacted with the babies by means of real-time videoconferencing, babies enjoyed it. But when there was a time delay of a few seconds, the babies became agitated.

The psychologist Amanda Woodward designed a looking-time study to demonstrate that
babies know that individuals have goals. First, a baby was placed in front of two objects and watched a hand reach for one of these objects. Then experimenters reversed the objects’ locations. Babies expected
that when the hand reached again, it should go for the same object, not the same location. This expectation was special to hands; if they saw a metal claw reaching for the object, the result went away.