What is object permanence?

0:00 Welcome to Philosophy is not boring by kidopoly.com. I'm Mira. And I'm Finn. Before we dive in today, a very happy belated birthday to Oscar in Chamonix-Mont-Blanc in the French Alps.

0:14 Wow, the French Alps! Happy birthday, Oscar! I bet playing hide and seek in the snow there is amazing. Which actually ties perfectly into today's big question.

0:24 It really does! Oh, and if you haven't already, tap follow wherever you're listening so you never miss an episode.

0:32 So, Mira, what is this big question?

0:35 Have you ever played Peekaboo with a tiny baby?

0:38 Haha, yeah, of course. You cover your face, say, Where did Finn go? and then pop out and they just lose their minds laughing. It's the easiest game ever.

0:50 It really is. But have you ever stopped to wonder why they find it so funny?

0:55 I just thought I had a really funny face. Or maybe they just like the surprise of someone jumping out. I mean, if someone jumped out from behind a door at me, I'd probably laugh. After I stopped screaming.

1:08 Well, what if I told you that to a baby? You didn't just hide behind your hands. You actually vanished from the universe.

1:15 Wait, what? They think I just popped out of existence? Like a ghost.

1:20 Yes, today we are exploring one of the coolest ideas about how our minds grow. We are going to look at why the you from when you were a baby thought entirely differently than you do right now.

1:32 So I used to think people were just disappearing and reappearing all day long. That sounds exhausting.

1:38 It probably was. But to understand this, we have to go back in time. For hundreds of years, people used to think that babies and kids were just miniature adults.

1:49 Like they had the exact same brains as grown-ups, just smaller.

1:54 Exactly. People thought a child's mind was just an empty bucket, waiting to be filled with facts. They thought kids just knew less than adults.

2:04 Like a computer that just hasn't downloaded enough files yet.

2:08 Perfect way to put it. They assumed if you just talk to a child like an adult, they would understand it, but maybe just not have the vocabulary to talk back. But in the 1920s, a Swiss thinker named Jean Piaget decided to really look at this.

2:24 Did he have a huge fancy laboratory with babies in white coats crawling around taking notes?

2:31 Nope. He just watched his own three children. He lived in Geneva, Switzerland, and he carried a notebook around, paying very close attention to the mistakes they made when they were playing.

2:43 Mistakes? Like eating dirt. Because I definitely ate dirt when I was a toddler. It wasn't my best moment.

2:51 Well, maybe dirt too, but he was looking at puzzles. He noticed that if he took a shiny toy and put it right in front of his baby, the baby would reach for it happily. But the exact second he threw a cloth over the toy. The baby pulled the cloth off to get it. No, that's the amazing part. Before a certain age, the baby just stopped reaching.

3:16 They didn't look confused, they didn't try to dig for it. They just looked away and moved on to something else.

3:23 Wait, you're saying if they couldn't see it, they just gave up.

3:27 Piaget believed it was more than giving up. He said that to a baby, the toy was completely gone. Out of sight didn't just mean hidden, it meant the toy ceased to exist entirely.

3:40 That is so weird. Imagine if every time you closed your eyes, you thought your bedroom, your toys, and the whole world just disappeared into thin air.

3:50 It would be terrifying, but also kind of magical when it came back. Piaget gave this idea a name. He called it object permanence. Object perma what? Permanence. It means something is permanent. It stays there. Object permanence is the understanding that a thing still exists even when you can't see it, hear it, or touch it.

4:15 Okay, so my toy dinosaur has object permanence. My bed is still in my room even when I'm at school. I know these things don't just melt away.

4:24 Yes, you understand that now, but Piaget said that babies under about eight months old haven't built that idea in their brains yet. They are in what he called the sensory motor stage. What does that mean? It means they only understand the world through their senses, what they can see, hear, and touch right in that exact second.

4:47 So that is exactly why peekaboo works.

4:50 Yes. Think about it from the baby's point of view. You cover your face with your hands. To the baby, your face isn't hiding, it is gone, erased.

5:01 And then I move my hands, and boom, I suddenly magically appear out of nowhere. No wonder they laugh so hard.

5:08 Exactly! You are performing the greatest magic trick in the world every single time.

5:15 But why does it have to take eight months? Why aren't we just born knowing things are still there?

5:20 That was Piaget's biggest claim of all. He said we don't just soak up facts like a sponge. At every stage of growing up, our brains actually think differently.

5:32 Like we have completely different operating systems.

5:35 Yes, and you can't just skip ahead to the adult operating system. You have to live through the baby one, where things disappear, so you can slowly learn how the physical world works by dropping things, touching things, and testing them over and over.

5:51 So Piaget just solved it. Babies absolutely don't know things exist when they can't see them. Case closed?

5:59 Well, here is where it gets interesting. Because good science and good philosophy are always about testing ideas. They don't just stop at one answer. Oh, did someone disagree with him? I love when they argue. They didn't exactly argue, but years later, other researchers, like a scientist named Renée Baillageon, started testing babies in new ways.

6:22 How do you test a baby? You can't exactly give them a written exam with a pencil.

6:27 No, you can't. So they used eye tracking. They carefully measured how long babies stared at things. If something surprising or impossible happens, a baby will stare at it much longer than something boring.

6:40 Oh, that makes sense. Like if I saw a flying dog, I'd stare at it for like ten minutes.

6:47 Right. So they showed babies a trick where a toy car rolled down a track, but then seemed to pass straight through a solid block that was hidden behind a screen. And they found that babies as young as three or four months old stared at it for a really long time.

7:02 Meaning they were surprised, which means they did know the solid block was supposed to be there, even when it was hidden.

7:08 Exactly. So modern science tells us Piaget might have been slightly off about the exact age. Babies might understand object permanence earlier than eight months. Why did Piaget think they didn't then? Well, think about his test. He wanted them to reach for the blanket. Maybe the babies just didn't know how to coordinate their hands to pull the blanket off yet.

7:30 Their brains knew the toy was there, but their motor skills just couldn't get it.

7:34 Oh wow. So Piaget's question was brilliant, but we had to invent new ways to check his answer.

7:40 Yes, but his massive idea still holds true. Kids are not just small adults, their minds are actively building reality step by step, stage by stage.

7:52 That's actually kind of mind-blowing. It makes me feel a bit bad for getting annoyed at toddlers sometimes. What do you mean? Well, like if a two-year-old throws a huge tantrum because you broke their cookie in half, and they think they have less cookie now. I always think it's the exact same amount of cookie.

8:11 You just have two pieces.

8:13 But to them it might not be. Their brain is at a stage where maybe they just see more pieces, or smaller pieces, and they can't reverse the logic yet. They aren't trying to be annoying, they are just literally seeing a different world.

8:28 So next time my little cousin cries because his mum walked into the kitchen, I should remember that his brain might literally be worried she's gone forever.

8:37 Exactly! It's a great reminder to be patient with people who are younger than you. They have to live through that stage to get to the next one. They are busy building their reality.

8:47 Okay, I have a weird question. Do animals have object permanence? Because if I throw a ball into the bushes, my dog will definitely go digging for it until he finds it.

8:58 They do. Dogs, cats, and especially certain birds like crows, are incredibly good at object permanence. They know the ball didn't vanish.

9:08 Ha! So a crow would not be impressed by my peekaboo game.

9:12 Not at all. The crow would just look at you, completely unamused, knowing your face is right behind your hands.

9:19 Ha, tough crowd. But I love that Piaget just figured all this out by sitting in his living room in Geneva in the 1920s, just watching his kids play.

9:29 The best puzzles are sometimes right in front of us, just waiting for someone to ask the right question. Alright, Finn, it is time for the quiz. Are you ready?

9:39 Okay, I'm ready. Let's do this.

9:42 First question. What was the name of the Swiss thinker who studied how babies learn? Next one. What city in Switzerland was he working in during the 1920s? Question 3. What is the two-word term for knowing a thing is still there, even when it's hidden? Here's number four. According to modern eye tracking tests, do babies understand this concept earlier or later than originally thought.

10:21 Last question. What classic game is basically a magic trick for babies because they think you actually disappeared? Great job! Let's see how you did. The first answer is Jean Piaget. For question two, he was working in Geneva. The answer to question three is object permanence. For question four, modern tests show they might understand it earlier, around three or four months.

10:53 And the final answer is Peekaboo! It is so wild to think we all used to believe our parents vanished into thin air when they played Peekaboo.

11:03 Honestly, I kind of wish I remembered what that felt like. It must have been pretty amazing.

11:09 It really must have been. Hey, if you like learning about how your baby brain worked, please leave us a five-star review.

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11:23 Make sure you follow this show, and we have sister shows too. History and science is not boring, and maths is not boring.

11:32 Go give those a listen and a follow as well. And if you want a shout out on the show or just want to say hi, email us at hello at kidopoly.com.

11:41 See you next time on Philosophy is not boring. Bye, everyone.