What going on in this baby’s mind? If you’d asked people this 30 years ago, most people, psychologists, would have said that this baby was irrational, illogical, egocentric — that he couldn’t the perspective of another person or understand cause and effect. In the last 20 years, developmental has completely overturned that picture. So in some ways, think that this baby’s thinking is like the thinking of the brilliant scientists.
Let me give you just one example of this. One that this baby could be thinking about, that could be going on in his mind, is trying to out what’s going on in the mind of that baby. After all, one of the things that’s hardest for of us to do is to figure out what other are thinking and feeling. And maybe the hardest thing of is to figure out that what other people think and isn’t actually exactly like what we think and feel. who’s followed politics can testify to how hard that is for some people to get. We wanted know if babies and young children could understand this profound thing about other people. Now the question is: How we ask them? Babies, after all, can’t talk, and you ask a three year-old to tell you what he thinks, you’ll get is a beautiful stream of consciousness monologue ponies and birthdays and things like that. So how do we actually ask them the question?
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it turns out that the secret was broccoli. What we — Betty Rapacholi, who was one of my students, I — was actually to give the babies two of food: one bowl of raw broccoli and one of delicious goldfish crackers. Now all of the babies, in Berkley, like the crackers and don’t like the raw broccoli. (Laughter) But then what Betty did to take a little taste of food from each bowl. And she would as if she liked it or she didn’t. So half the time, she as if she liked the crackers and didn’t like the — just like a baby and any other sane person. But the time, what she would do is take a little of the broccoli and go, “Mmmmm, broccoli. I tasted the broccoli. Mmmmm.” And she would take a little bit of the crackers, she’d go, “Eww, yuck, crackers. I tasted the crackers. Eww, yuck.” she’d act as if what she wanted was just the of what the babies wanted. We did this with 15 and 18 month-old babies. then she would simply put her hand out and say, “Can you give some?”
So the question is: What would the baby her, what they liked or what she liked? And the remarkable thing was 18 month-old babies, just barely walking and talking, would give her the crackers she liked the crackers, but they would give her the broccoli she liked the broccoli. On the other hand, 15 month-olds would at her for a long time if she acted as if she the broccoli, like they couldn’t figure this out. But then after they stared for long time, they would just give her the crackers, what they thought everybody must like. there are two really remarkable things about this. The first one is that these 18 month-old babies have already discovered this really profound fact about nature, that we don’t always want the same thing. what’s more, they felt that they should actually do to help other people get what they wanted.
Even more though, the fact that 15 month-olds didn’t do this suggests that 18 month-olds had learned this deep, profound fact about human nature in the three months from when they 15 months old. So children both know more and more than we ever would have thought. And this just one of hundreds and hundreds of studies over last 20 years that’s actually demonstrated it.
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The you might ask though is: Why do children learn so much? And how it possible for them to learn so much in such short time? I mean, after all, if you look babies superficially, they seem pretty useless. And actually in ways, they’re worse than useless, because we have to put so much time and into just keeping them alive. But if we turn to evolution for an answer this puzzle of why we spend so much time taking care of useless babies, it turns out there’s actually an answer. If we look across many, different species of animals, not just us primates, but including other mammals, birds, even marsupials like kangaroos and wombats, it out that there’s a relationship between how long a a species has and how big their brains are compared to their bodies and how smart and flexible are.
And sort of the posterbirds for this idea are the birds up there. On one side is New Caledonian crow. And crows and other corvidae, ravens, and so forth, are incredibly smart birds. They’re as as chimpanzees in some respects. And this is a bird on cover of science who’s learned how to use a tool to food. On the other hand, we have our friend domestic chicken. And chickens and ducks and geese and are basically as dumb as dumps. So they’re very, very good at pecking for grain, and they’re not good at doing anything else. Well it turns out the babies, the New Caledonian crow babies, are fledglings. depend on their moms to drop worms in their little open mouths as long as two years, which is a really long time the life of a bird. Whereas the chickens are actually mature within a of months. So childhood is the reason why the crows end on the cover of Science and the chickens end up in soup pot.
There’s something about that long childhood that to be connected to knowledge and learning. Well what of explanation could we have for this? Well some animals, like chicken, seem to be beautifully suited to doing just one thing very well. they seem to be beautifully suited to pecking grain one environment. Other creatures, like the crows, aren’t very at doing anything in particular, but they’re extremely good at learning laws of different environments.
And of course, we human beings are out on the end of the distribution like the crows. We have brains relative to our bodies by far than any animal. We’re smarter, we’re more flexible, we can learn more, we survive more different environments, we migrated to cover the world and even to outer space. And our babies and children are on us for much longer than the babies of other species. My son is 23. (Laughter) And at least until they’re 23, we’re still those worms into those little open mouths.
All right, why would we see correlation? Well an idea is that that strategy, that strategy, is an extremely powerful, great strategy for getting on in world, but it has one big disadvantage. And that big disadvantage is that, until you actually do all learning, you’re going to be helpless. So you don’t to have the mastodon charging at you and be saying to yourself, “A slingshot maybe a spear might work. Which would actually be better?” want to know all that before the mastodons actually show up. And the the evolutions seems to have solved that problem is with a kind division of labor. So the idea is that we this early period when we’re completely protected. We don’t have to do anything. All we have to is learn. And then as adults, we can take those things that we learned when we were babies and children actually put them to work to do things out in the world.
So one way of thinking about it is that babies and young children are the research and development division of the human species. So they’re the protected blue sky who just have to go out and learn and have good ideas, and we’re production and marketing. have to take all those ideas that we learned when we children and actually put them to use. Another way of about it is instead of thinking of babies and children as being defective grownups, we should think about them as being a different stage of the same species — kind of like and butterflies — except that they’re actually the brilliant who are flitting around the garden and exploring, and we’re the who are inching along our narrow, grownup, adult path.
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this is true, if these babies are designed to learn — and this evolutionary story would say are for learning, that’s what they’re for — we expect that they would have really powerful learning mechanisms. in fact, the baby’s brain seems to be the most powerful learning computer on the planet. But real are actually getting to be a lot better. And there’s been revolution in our understanding of machine learning recently. And all depends on the ideas of this guy, the Thomas Bayes, who was a statistician and mathematician in the 18th century. essentially what Bayes did was to provide a mathematical way using probability theory characterize, describe, the way that scientists find out about world. So what scientists do is they have a hypothesis that they might be likely to start with. They go out and it against the evidence. The evidence makes them change that hypothesis. Then test that new hypothesis and so on and so forth. And what Bayes showed was a mathematical way that could do that. And that mathematics is at the core of the machine learning programs that we have now. And some 10 years ago, I suggested that might be doing the same thing.
So if you want to know what’s going underneath those beautiful brown eyes, I think it actually looks something this. This is Reverend Bayes’s notebook. So I think those babies are actually making complicated calculations conditional probabilities that they’re revising to figure out how the works. All right, now that might seem like an even order to actually demonstrate. Because after all, if you ask even grownups statistics, they look extremely stupid. How could it be children are doing statistics?
So to test this we a machine that we have called the Blicket Detector. is a box that lights up and plays music when put some things on it and not others. And using this very simple machine, my lab and have done dozens of studies showing just how good babies are at learning about the world. Let mention just one that we did with Tumar Kushner, student. If I showed you this detector, you would likely to think to begin with that the way to make detector go would be to put a block on of the detector. But actually, this detector works in a bit of a strange way. Because you wave a block over the top of the detector, something wouldn’t ever think of to begin with, the detector will actually activate two out three times. Whereas, if you do the likely thing, put the block on the detector, it will only two out of six times. So the unlikely hypothesis actually has stronger evidence. It looks if the waving is a more effective strategy than the other strategy. So we did just this; we four year-olds this pattern of evidence, and we just asked them to make it go. sure enough, the four year-olds used the evidence to the object on top of the detector.
Now there are two things that are interesting about this. The first one is, again, remember, are four year-olds. They’re just learning how to count. But unconsciously, they’re doing these complicated calculations that will give them a conditional probability measure. And the other interesting thing is that they’re that evidence to get to an idea, get to hypothesis about the world, that seems very unlikely to begin with. And in studies we’ve just doing in my lab, similar studies, we’ve show that four year-olds are actually better at out an unlikely hypothesis than adults are when we them exactly the same task. So in these circumstances, the children are statistics to find out about the world, but after all, scientists also do experiments, and we to see if children are doing experiments. When children do experiments we call it “getting everything” or else “playing.”
And there’s been a bunch interesting studies recently that have shown this playing around is really a kind of research program. Here’s one from Cristine Legare’s lab. What Cristine did was use our Blicket Detectors. And what did was show children that yellow ones made it go and red ones didn’t, and then showed them an anomaly. And what you’ll see is that this boy will go through five hypotheses in the space of minutes.
(Video) Boy: How about this? Same as the other side.
Alison Gopnik: Okay, so his hypothesis has just been falsified.
(Laughter)
Boy: This one lighted up, and this one nothing.
AG: Okay, he’s his experimental notebook out.
Boy: What’s making this light up. (Laughter) I don’t know.
AG: Every scientist recognize that expression of despair.
(Laughter)
Boy: Oh, it’s because this needs be like this, and this needs to be like this.
AG: Okay, two.
Boy: That’s why. Oh.
(Laughter)
AG: Now this is his next idea. He the experimenter to do this, to try putting it onto the other location. Not working either.
Boy: Oh, the light goes only to here, not here. Oh, the bottom this box has electricity in here, but this doesn’t have electricity.
AG: Okay, that’s fourth hypothesis.
Boy: It’s lighting up. So when you put four. So you put four this one to make it light up and two on this one to make it up.
AG: Okay,there’s his fifth hypothesis.
Now that is a particularly — that is a adorable and articulate little boy, but what Cristine discovered is this is actually quite typical. If look at the way children play, when you ask them to explain something, what really do is do a series of experiments. This is pretty typical of four year-olds.
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Well, what’s like to be this kind of creature? What’s it like to be one of these brilliant butterflies can test five hypotheses in two minutes? Well, if you go back to those psychologists and philosophers, lot of them have said that babies and young children were barely if they were conscious at all. And I think the opposite is true. I think babies and children are more conscious than we are as adults. Now here’s what we know how adult consciousness works. And adults’ attention and consciousness look kind of a spotlight. So what happens for adults is we that something’s relevant or important, we should pay attention to it. Our consciousness of thing that we’re attending to becomes extremely bright and vivid, everything else sort of goes dark. And we even know something the way the brain does this.
So what happens when we pay attention is that the cortex, the sort of executive part of our brains, sends a signal that a little part of our brain much more flexible, more plastic, better at learning, and down activity in all the rest of our brains. So have a very focused, purpose-driven kind of attention. If we look babies and young children, we see something very different. I think and young children seem to have more of a of consciousness than a spotlight of consciousness. So babies and young children are very bad at narrowing down just one thing. But they’re very good at taking in lots information from lots of different sources at once. And if you actually look their brains, you see that they’re flooded with these neurotransmitters that are really good inducing learning and plasticity, and the inhibitory parts haven’t come on yet. So when we that babies and young children are bad at paying attention, what we really mean is that they’re bad not paying attention. So they’re bad at getting rid of all the interesting things could tell them something and just looking at the that’s important. That’s the kind of attention, the kind of consciousness, that might expect from those butterflies who are designed to learn.
Well we want to think about a way of getting taste of that kind of baby consciousness as adults, I think the best thing is think about where we’re put in a new situation that we’ve never been in — when we fall in love with someone new, when we’re in a new city for the first time. what happens then is not that our consciousness contracts, it expands, so that those three in Paris seem to be more full of consciousness and experience than all months of being a walking, talking, faculty meeting-attending zombie back home. And by way, that coffee, that wonderful coffee you’ve been drinking downstairs, actually mimics the of those baby neurotransmitters. So what’s it like to be a baby? It’s like being love in Paris for the first time after you’ve had three double-espressos. (Laughter) That’s a fantastic to be, but it does tend to leave you waking crying at three o’clock in the morning.
(Laughter)
Now it’s to be a grownup. I don’t want to say much about how wonderful babies are. It’s good to a grownup. We can do things like tie our shoelaces cross the street by ourselves. And it makes sense we put a lot of effort into making babies like adults do. But if what we want is to be like butterflies, to have open-mindedness, open learning, imagination, creativity, innovation, maybe at least some of the we should be getting the adults to start thinking like children.
(Applause)