What's going on in a 4‑ or 5‑year‑old's mind?
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A cookie tin — open it, and inside are crayons. Ask a three-year-old: Dad hasn't opened it — what will he think is inside? Before you watch on, take a guess at his answer.
The three-year-old says: crayons. Now ask a five-year-old. A little grin. Cookies! Dad's going to be fooled. Stranger still, ask the three-year-old what he himself thought a minute ago. Crayons, he says.
In those one or two years, something new appears in a child's mind. Picture it: everyone has a little room in their head. Whatever your eyes see goes into your own room. A three-year-old thinks the whole family shares one room. If it's in my room, it's in yours.
Around four or five, he finds out the rooms are separate. Dad never saw the crayons, so Dad's room still holds cookies. Psychologists pooled more than 170 studies like this. Around four, about half of kids get it right; past five, about eight in ten. Some countries a bit earlier, some later — but always in this order.
Once the rooms split, a child discovers something new. I can put something untrue into your room. Chocolate all around his mouth: I didn't eat it. That's a lie.
One experiment found a group of three-year-olds who had never lied. Half got six short lessons in guessing what other people know and don't know. The other half practised counting. After a hide-the-candy game, the mind-guessing group started to fib. A month later, they still did.
So a small lie at four or five usually isn't a child going bad. It's the first time he understands: what's in your head isn't what's in mine. So should we just let lying go? Not quite. Researchers compared two preschools. At one, kids were often hit — nearly every child who peeked at a toy lied. At the other, just over half.
The harsher the punishment, the tighter a child locks the truth in his room. Another study read stories to kids aged three to seven. A nose that grows with every lie? No effect. A child who owns up and gets praised? Far more told the truth. Next time he owns up, start with: thank you for telling me.
Separate rooms bring other skills too. He can keep a secret — like the card he's secretly drawing for you. A little later, he'll see this too: a smile on the door can hide a sad room inside. At four or five, a child discovers something big: everyone has a little room of their own.
What's the funniest fib your kid has ever told?
A cookie tin full of crayons
Put crayons in a cookie tin and ask your child: Dad hasn't opened it — what will he think is inside?
You can try it at home. Psychologists did this decades ago with a candy tube full of pencils.
Everyone has a little room in their head
Whatever your eyes see goes into your own room.
At three, kids think the whole family shares one room. At four or five, they find out the rooms are separate.
Dad never saw the crayons, so Dad's room still holds cookies. A toddler looks at you after a fall to borrow your read on things; by four or five, he realizes what's in your head can differ from what's in his.
Around age four, the rooms split
Psychologists pooled more than 170 studies like this: around four, about half of kids get it right; past five, about eight in ten.
Some countries are a bit earlier, some later, but the order is the same — children in Beijing go step by step too. Six months either way is normal.
Chocolate on his mouth: "I didn't eat it"
Once the rooms split, a child discovers he can put something untrue into your room. That's a lie.
So a small lie at four or five usually isn't a child going bad. It's the first time he understands: what's in your head isn't what's in mine.
When he lies, how should you respond?
Next time he owns up, start with: thank you for telling me.
Two new skills the room brings
Quick check
A five-year-old says "Dad will think it's cookies." What has he figured out?
Everyone has their own little room in their head: Dad never saw the crayons, so his room still holds cookies.
