Mason and Blazek spent hours with those monkeys, and they got to know them well. They wanted the babies to grow strong and healthy. Mason planned to continue some of the earlier studies on curiosity. Harry had established that monkeys were naturally curious, and Mason wondered how early that trait showed up. When did monkeys start to wonder about the world around them? Were they born asking questions or did they pick it up later? When it came to puzzles, at least, Mason and Blazek found that the Stone babies were naturals. As soon as they were coordinated enough to work a puzzle, the little creatures were busy trying to solve it. The results reinforced a strong suspicion that curiosity was fundamental to the way these small primates approached the world.

  Something else about the Stone monkeys caught the lab workers’ attention. The researchers had been lining the cages with cloth diapers to provide a little softness and warmth against the floor. All the little monkeys, including those in the Stone family, were absolutely, fanatically attached to those diapers; they not only hugged the diapers fiercely but also wrapped themselves in the white cloth, clutched at it desperately if someone picked them up. Around the lab, an observer might be struck by the appearance of baby monkeys in transit, cloth streaming out behind them like kite tails.

  There was already a hint about this cloth-obsession from the nineteenth century, in the diaries of a British naturalist named Alfred Russel Wallace. The adventurous Wallace is best remembered now because he so nearly published a theory of evolution before Charles Darwin. As with Darwin, it was traveling that made the theory come to life. Exploring the oddly different and beautifully adapted species of each country also made Wallace think about the way nature tucks us into our niches. During a visit to Indonesia, Wallace had been given an orphaned baby orangutan. He wrote in his journal that the little animal seemed to constantly reach for and cuddle soft material, including (painfully) Wallace’s beard. Trying to help the baby and himself, Wallace made what he called a “stuffed mother” out of a roll of buffalo skin. He noted that the little ape clung happily to the fat, fuzzy roll, no longer interested in random beards and shirts.

  And there was another, more recent, clue from a Yale University researcher famed for her meticulous comparisons of monkey and human anatomy. To make a detailed analysis, Gertrude Van Wagenen had needed a reliable supply of monkeys. She’d created a small nursery and written an insightful chapter on her technique for raising baby monkeys. Van Wagenen had found that her nursery-raised monkeys bonded almost compulsively to the soft blankets lining their baskets. She described their tight clutch as emotional dependency, and noted that if the infant monkeys couldn’t cuddle, some of them didn’t even develop proper feeding responses. “You know of the debt I owe to you for the creation of the rhesus baby in the basket,” Harry wrote to her, late in his career. “The early research, which I conducted according to your directions, started me off in the field of primate affection.”

  And, indeed, the psychologists in his primate lab were beginning to wonder whether there was a real message in the behavior of their baby monkeys. Perhaps the small animals had something to tell them about the needs of children; after all, it wasn’t monkeys alone who clung to soft cloth. Orangutans, too, did it, and other labs reported that baby chimpanzees desperately hugged blankets. Nancy Blazek and Bill Mason, watching their monkeys cling to the cloth, started wondering about that need to hold on. They had that other primate to consider in this idea, too. All of them knew that human babies, left alone in a crib, also clutched their quilts and pillows and fluffy stuffed toys. But what did that mean? What was the message in the apparent magic of cloth?

  Mason suggested to Harry that they run a test. He was thinking of a simple comparison between, say, a fat bundle of cloth and something hard—wood or wire. The researchers could see what the babies preferred—whether it was just the need to hold on to something, anything, or whether there was something especially meaningful about a soft touch.

  And the idea just clicked for Harry. He liked it immediately. He also thought there might be something even bigger lurking there. Perhaps the differences between cloth and wood touched on part of the underlying question only. After all, babies don’t prefer to hold on to pieces of cloth to all else. They hold onto them when there’s no human—or monkey—available for cuddling. The soft bits of cloth might be a substitute for something that mothers do that’s missing. Today, of course, we would include fathers, but this was the 1950s; and at that time, in science and society alike, it was mother who represented what parents had to give a child.

  So, if Harry was right, if they were looking at an odd, pathetic kind of mother substitute in these blankets, they were also looking at raising a revolution in psychology. If the baby monkeys were telling them that there was something critical in being touched, in being held and in holding back, then they could start rewriting the psychology books. And the first new sentence in that book might say that mothers themselves—with their soft arms and inclination to hold a baby close—were desperately important; and if that was right, the Watsonian, Skinnerian, Hullian view of the world could be nothing less than wrong.

  Harry used to say that the idea for a lab-built mother occurred to him on a Northwest Airlines flight between Detroit and Madison as he looked out at the puffy, deceptively soft clouds billowing on the other side of the glass. “As I turned to look out the window, I suddenly saw a vision of the cloth surrogate mother sitting beside me,” he wrote. A lab-created doll of a mother, as deceptively soft as those floating clouds, could be used to see what a baby really wanted. It would be a comparison, as Bill Mason suggested, but it would be a comparison that used a mother figure, one that looked obviously enough like a mother that anyone could see that this was not only about monkeys.

  Harry Harlow had encouraged the students and employees in his lab to think for themselves, and they didn’t hesitate in this instance. They thought he was wrong. As far as Harry could tell, his students thought that their major professor had left his head in the clouds: “My enthusiastic descent upon the laboratory was met by skepticism or lack of interest from one graduate student after another.” He was finally able, he said, to convince one of his newer graduate students, Robert Zimmermann, to give it a try. “But I’ll tell you one thing about those damn airplane rides when we were on the surrogate project,” says Zimmermann, now retired in Lansing, Michigan. “Every time Harry would fly somewhere—and he went away every week because he was on all kinds of committees—he’d run into some shrink or somebody and he would come back with some new idea about what we should be doing with the surrogate. He’d always wonder when he came back, ‘Why don’t we have this? So and so said we should have rocking, why don’t we have rocking?’”

  Zimmermann is laughing when he tells this story. He agrees that Harry was right about one thing—most of the students fled from getting sucked into a project as mushy, as un-Wisconsin, as mother love:

  In all honesty, nobody, no grad student wanted to touch the mother surrogate project with a ten-foot pole. This was Wisconsin, and Harry could be of some help, but you had to get your thesis or dissertation past a committee, and to talk about love at the University of Wisconsin, where everything was numbers and statistics ... I think the first assumption was that if you took that one you’d never graduate.

  Well, I was already working with neonatal learning and nothing much was being done with the babies in the first ninety days of life, before they were ready for those experiments, and I thought, well, I have an investment in these monkeys, so I made a deal with Harry. I would be the ramrod for the mother surrogate project if he would let me have the baby monkeys for my dissertation. And he thought that would be a fair trade.

  The airplane birth of the surrogate mother—the way Harry would tell it, full of drama and imagery—says a lot about Harry’s vision for the project. Here was science at its most provocative—mother love at a time when British psychiatrist John Bowlby could barely persuade his colleagues to join the words mother and love tog
ether. Here, also, was science with real potential to make a difference, to make people see families and relationships in a different way, a closer way. The first challenge would be getting anyone to take it seriously.

  That was going to take both solid research and, Harry suspected, all the skills at making an idea compelling that he had acquired over the years, all the unflinching stubbornness he had learned while he wangled a laboratory from the University of Wisconsin and persuaded his colleagues that maybe, just maybe, monkeys were smarter than scientists had thought. If he wanted an attentive audience—and, oh, he really did—the surrogate mother was going to be a Harry Harlow production.

  His newly minted Stanford researcher, Bill Mason, was stunned by how rapidly his small, neat idea became a showstopper. “I didn’t see it as a breakthrough or something really sensational,” Mason says. “It was a kind of demonstration with a foregone conclusion.” There was Wallace, after all, and there was Van Wagenen; everyone in the lab expected the monkeys to prefer the cloth. They worked out a kind of trial balloon. Zimmermann teamed with another graduate student, Lorna Smith, and the two of them did a simple first test with two baby monkeys. Both the little animals flatly rejected a wire object in favor of a cloth bundle. “It was unbelievably clear, amazing,” Zimmermann says, and suddenly the lab crew began to consider the possibility that Harry Harlow was going to pull this love stuff off after all.

  From that first experiment, Harry wanted everything nailed, every detail noted, every possible criticism identified and answered. He insisted on two observers for every experiment with the little animals, one student double-checking the other. He devised careful charts to score the monkeys’ behavior. Harry and his students filmed the experiments and then spent hours scrutinizing each frame, right down to the clasp of the fingers on the cloth. “He was concerned it would be rejected out of hand if we didn’t nail it to the floor,” Zimmermann says.

  Mason still remembers, with admiration, Harry’s skill at taking a long-dismissed idea—that mother love was a crucial part of a child’s development—and persuading his colleagues to listen to him. “The dominant position was that babies didn’t love their mothers or need them, that the only relationship was based on being fed,” Mason says. “It sounds silly now but that’s what people thought. Harlow sensed people were beginning to ask questions. And it was damn right to ask questions because the dominant position wasn’t true. These are facts—monkeys don’t just explore for food, they do it because they are curious, they have a drive to know. And they are social and they need to interact. Harlow had a great sense of when he could get away with challenging the field. If he had misjudged that—if he had been younger, less skillful—it would have been a disaster. People would have laughed.”

  Skillful or not, there was no doubt that Harry was yet again on the wrong side of behaviorist psychology. B. F. Skinner was now experimenting with boxes in which to raise young children. Skinner had built the first demonstration model for his younger daughter, Debbie. It was a crib-sized “living space”—a baby-tender, Skinner called it, with sound-absorbing walls, a large window, and a canvas floor. The air in the box was filtered and humidified and the baby stayed so clean in there that Skinner said she needed a bath only twice a week. The partial soundproofing meant that the child was undisturbed by doorbells and ringing phones—or the voices of her parents and sister. Debbie came out for scheduled playtimes and meals: “One whole side of the compartment is safety glass, through which we all talk and gesture to her during the day. She greets us with a big smile when we look at her through the window,” Skinner wrote in a letter to a friend, emphasizing the advantages of raising your baby in a box. He hoped that every mother would one day use a baby-tender. Skinner wrote once of being surprised when a pediatrician suggested that the box might be better used in hospitals where it could save nurses much work. It could save mothers work, too, Skinner replied. The doctor laughed. Mothers didn’t care so much about the saved labor, he assured the psychologist. Mothers labored out of love.

  “The universal reaction was, ‘What is this love?’” recalls former grad student Leonard Rosenblum. “The only emotions studied in animals were negative—fear, loathing, pain. The idea that animals were motivated by love, what vague notion was this?” Rosenblum makes a dismissive gesture, indicating the disdain of the time. It has been a long time since he was a fledgling psychologist himself. He recently retired as director of a primate laboratory in Brooklyn, part of the State University of New York system. Today, Rosenblum is an internationally known expert in developmental biology, an angular man with bright blue eyes and a slightly shaggy silvery beard. He retains, though, the same intensity and lively humor and flair for a dramatic turn of phrase that he had as a student in Harry’s laboratory.

  “Remember,” Rosenblum says, “that behaviorism’s beginnings, with John Watson, suggested that it was a great thing to dig holes in the backyard and let your kids fall in and learn about life. So in psychology, love was smoke, mirrors, bullshit, and that was exactly what everyone was telling Harry.” Of course, Harry was used to being told he was on the wrong of an issue, the backside of the fence. He’d come to kind of enjoy needling the smugness of the mainstream position. He simply began assembling more evidence. Beyond that, he thought about how to make that evidence look really, really good. Bill Mason had proposed that they look at how monkeys might hold on to a bundle of cloth. And that was a beginning, said Harry, but they needed their surrogate to look like more than a bundle. It needed personality. It needed a head and a face. If monkeys were going to look at this substitute mother, it needed to look back at them. And it needed to look back at the human observers, too; it needed to mean something real to people. Harry wanted them all—not just psychologists but mothers and fathers and aunts and uncles and stepparents and grandparents—to think about connection and affection. He wanted them to believe that emotions and relationships were the proper purview of research.

  Harry’s students still sometimes argue about the decision to put a head on the cloth mother. Mason considers the head merely showmanship, unnecessary to testing monkeys, who, after all, would happily cuddle with a diaper. Others consider it strategy. One such former student, Steve Suomi, now head of primate behavioral research at the National Institutes of Health, still thinks of the head as a brilliant tactical move. “So it might not have been relevant to monkeys,” Suomi says. “But it was to the outside world, because once people looked at the surrogate like a mother—made a connection to human mothers as well—then you could start talking about things like mother love.”

  And despite the fears by Mason, and even Bob Zimmermann, that the head was going to get them laughed out of psychology, Harry was absolutely determined. He had suddenly been given a first-class platform for his arguments. He’d finally—as Lewis Terman had predicted—been elected president of the American Psychological Association. And he was going use that position, he decided, to pound the podium and make his argument. He was absolutely sure of what he was going to argue. He had even thought of a title. He was going to call his talk “The Nature of Love.” And as Zimmermann still remembers, “He came back into the laboratory and said to me, ‘Bob, I have written one of the finest speeches ever delivered to the APA as president. Go get me the data.’”

  So they put a plain wooden ball on top of the bundled body. Harry still wasn’t satisfied. “It doesn’t have a face,” he said. By this time, Bob Zimmermann had fully taken over the construction project and he was willing, if he had to, to put a face on the surrogate mother. Harry had recruited Zimmermann, a tall, lanky man with dark hair trimmed into a ruthless crewcut, from Lehigh University in Pennsylvania. He was a promising and ambitious young psychologist. Zimmermann had received three offers from graduate schools, but Harry had written “the most beautiful letter” about Wisconsin and the land and the support the school could offer. After Zimmermann was properly seduced, he remembers, Harry wanted the letter back. It had worked so well that he wanted to try
it on the next year’s crop of recruits.

  Zimmermann took the problem of the cloth mother’s face to the lab’s resident equipment-building genius, Art Schmidt. Schmidt was another typical Harry Harlow hire. He was a geography major and a hell of a handy guy. Even in his seventies, Schmidt remained lightly, toughly built. He still raced cars for fun. He had steady blue eyes and a slow smile. “I can build anything,” he says simply. To help pay his way through school, Schmidt took a 90-cents-an-hour job at the primate lab, where he repaired cages and put up storm windows. When Schmidt graduated in 1953, Harry offered him a full-time job. Schmidt had gradually lost his enthusiasm for geography and he thought Harry would be a good boss. “He’d always go to bat for you if he thought you did a good job,” he said. The new job partly required that he listen to the young researchers—who were all thumbs, according to Harry—and build their ideas into something functional.

  Schmidt built the Butler box and long remembered Harry showing it off to visiting air force officials:It was to test how curious the monkeys were. There was a door they could push open and you could record how often they pushed it. I made a motor to open and close the door. The door would just wham down, and the monkeys were smart as hell, they’d just jump out of the way. And then they’d open it again. When these three or four colonels came, we all put on our clean lab coats, set up the box, and Harlow said, “This is Mr. Schmidt who built this and when Art Schmidt builds something it works.” And then the door jammed. I was so embarrassed. But Harry just laughed. He said, “Except maybe today.”