Cognitive and Moral Development: Piaget, Vygotsky, and Kohlberg

When Your Mind Changes

Think about the last time you changed your mind about something you were completely sure of.

Maybe it was something about money.

Maybe it was what makes someone a good parent.

Maybe it was something small, like finding out the way you’ve loaded the dishwasher for ten years is apparently wrong.

Here’s what’s interesting about that moment.

Your mind didn’t just pick up a new fact.

Something about the way you organize the world had to shift.

And you have been doing that since the day you were born.

You were not born knowing that your mom still exists when she walks out of the room.

You were not born knowing that a tall, skinny glass and a short, wide glass can hold the exact same amount of juice.

And you were definitely not born knowing that stealing might feel wrong in one situation and complicated in another.

Your mind had to build all of that, piece by piece.

And so did your sense of right and wrong.

Three Big Questions

Psychologists have spent decades asking how that happens.

And today we’re going to look at three big answers.

Jean Piaget asked, “How does thinking change?”

Lev Vygotsky asked, “How do other people help thinking grow?”

And Lawrence Kohlberg asked, “How does our reasoning about right and wrong change?”

Welcome back to The Psychology Notebook.

I’m Desiree, and this is lesson twenty-one in our Psych 101 series.

And don’t forget, you can find study guides, templates, freebies, and fun accessories for your psychology notebook at thepsychologynotebook.com.

The link is down below.

The House Metaphor

Now, to keep all three of these ideas straight, I want you to picture something.

Imagine your mind is a house.

Not a finished house.

A house that is being remodeled while you are still living in it.

Piaget is going to show us the remodeling: how the rooms get rearranged and how sometimes a wall has to come down.

Vygotsky is going to show us the crew: the people who show up with tools, ladders, and scaffolding so you can build something you could never build alone.

And Kohlberg is going to show us the floors.

Because the higher up you go in this house, the more of the neighborhood you can see.

And at the very end, we’re going to invite in a building inspector.

Because every good theory deserves someone who checks its work.

Ready?

Let’s start with the remodel.

Piaget: Building Mental Frameworks

Jean Piaget was a Swiss psychologist who spent a huge part of his career doing something that sounds almost too simple.

He watched children, including his own.

And what he noticed changed how we think about kids.

Before Piaget, a lot of people treated children like smaller adults who just knew less.

Piaget said, “No, children don’t just know less. They think differently. They see the world through a different set of blueprints.”

He called those blueprints schemas.

A schema is a mental framework, a kind of floor plan your mind uses to organize and make sense of what you experience.

Assimilation and Accommodation

A toddler has a schema for dog.

Four legs. Fuzzy. Barks. Wags its tail.

Now the toddler sees a cat for the first time and says, “Dog.”

That is not a mistake in the way we usually think about mistakes.

That’s the toddler taking something new and fitting it into a floor plan that already exists.

Piaget called that assimilation.

Think of it as rearranging the furniture.

You’re not changing the house. You’re just finding a spot for the new couch.

But then somebody says, “Nope, that’s a cat.”

And the cat doesn’t act like the dog.

It meows. It’s aloof. It does not care about the toddler at all.

Now the old floor plan doesn’t work.

Something has to change.

So the toddler builds a new category, a new room.

Piaget called that accommodation.

That’s knocking down a wall.

Equilibration

And here’s the part I love.

Piaget said that little uncomfortable feeling when what you know doesn’t match what you’re seeing is what pushes us forward.

He called the balancing act between the two equilibration.

Your mind is always trying to get back to feeling like things make sense.

You know that feeling when a software update moves every single button on your phone?

That’s disequilibrium.

You are personally being remodeled.

This is a notebook moment.

Get out your psychology notebook and write this down.

A schema is a mental framework we use to organize information.

Assimilation is fitting new information into an existing schema.

Accommodation is changing the schema when new information doesn’t fit.

Piaget’s Four Stages

Okay. Now, Piaget believed this remodeling happens in four big stages.

The Sensorimotor Stage

Stage one is the sensorimotor stage.

From birth to about age two, babies learn through their senses and their actions.

Look. Grab. Shake. Drop. Put it in the mouth.

And somewhere around eight months, Piaget said, babies begin to grasp object permanence.

The idea that something still exists even when you can’t see it.

Which is one reason peekaboo is such a big deal to babies.

Now you see me. Now you don’t.

And now you’re learning something.

The Preoperational Stage

Stage two is the preoperational stage, roughly ages two to seven.

Language explodes. Pretend play explodes.

A banana becomes a phone.

But thinking is still tied to how things look.

And it’s very self-centered.

Piaget called this egocentrism.

It doesn’t mean selfish.

It means a young child has a hard time picturing that someone else sees the world differently than they do.

In his famous three-mountains task, a child would look at a model of mountains and be asked what a doll sitting on the other side could see.

Young children usually describe their own view.

And this is the stage where you get that famous juice moment.

You pour the same amount of juice into a tall, skinny glass and a short, wide glass.

And a preschooler will tell you the tall one has more because it looks like more.

The Concrete Operational Stage

Stage three is the concrete operational stage, roughly ages seven to eleven.

Now logic shows up, but for real, tangible things.

Children understand that the juice is still the same amount because they can mentally reverse it.

They know you could just pour it back.

That’s called conservation.

The Formal Operational Stage

And stage four is the formal operational stage, from about age twelve on.

This is where thinking can leave the physical world.

Abstract ideas. What-if questions. Hypotheticals. Thinking about your own thinking.

This is another notebook moment.

Write down the four stages with the ages.

Sensorimotor: birth to about two.

Preoperational: about two to seven.

Concrete operational: about seven to eleven.

Formal operational: about twelve and up.

The Building Inspector: Reviewing Piaget

Now, here comes our building inspector for the first time.

Because Piaget’s ideas are still taught everywhere, but researchers have poked some real holes in them.

In 1974, two researchers named McGarrigle and Donaldson ran a version of the juice test with a naughty teddy bear.

When the experimenter deliberately changed things, only about 16% of the kids got it right.

But when the teddy messed things up by accident, about 62% got it right.

Same logic. Different situation.

So maybe the kids weren’t lacking the logic.

Maybe the original question was confusing them.

Think about it.

If an adult asks you the same question twice, you assume your first answer was wrong.

And in 1991, Baillargeon and DeVos found that babies as young as around four months old looked longer at impossible events, like a hidden object seeming to vanish, which suggests babies understand more than Piaget’s tasks gave them credit for.

And here’s one that matters for us as adults.

Some research suggests that not everyone reaches formal operational thinking or uses it in every part of life.

One review of the research reports that only about a third of adults do it consistently.

Which means the top floor of Piaget’s house isn’t automatic.

It depends on experience, education, and what you’ve had the chance to practice.

So the takeaway is this.

Piaget gave us a powerful picture of thinking as something we actively build.

But the ages are more like general patterns than exact deadlines.

But there’s one thing Piaget’s remodel doesn’t tell us much about.

Who else is in the house?

Vygotsky: Nobody Builds Alone

That’s where Lev Vygotsky comes in.

Vygotsky was a Russian psychologist born in 1896 who died young, at just thirty-seven.

And in the short time he had, he offered a different picture of the house.

Piaget pictured the child as a kind of lone scientist exploring the world and figuring it out mostly on their own.

Vygotsky said, “Hold on. Nobody builds a house alone.”

His big idea was that thinking starts between people and then moves inside you.

You learn to count because someone counts with you.

You learn to tell a story because someone tells stories to you.

You learn how to handle frustration because someone sits with you while you’re frustrated.

First, it’s social. Then it becomes yours.

The Zone of Proximal Development

And the most famous idea that came out of that is the zone of proximal development.

I know it’s a mouthful.

Everybody calls it the ZPD.

Here’s the simple version.

Picture three zones.

Zone one is everything you can already do on your own.

You’ve got this. No help needed.

Zone three is everything that’s still way too hard, even if someone helps you.

Not yet.

But right in the middle is zone two.

The stuff you can’t do alone, but you can do with the right help.

That’s the zone of proximal development.

And Vygotsky said that middle zone is where the real learning happens.

Think about your first week at a new job.

You couldn’t do the whole thing alone, but you also weren’t drowning because someone sat next to you and said, “Okay, watch me do it once. Now you try.”

That was your ZPD.

And a few weeks later, you were doing it without thinking twice.

That’s the whole idea.

What you can do with help today, you can often do on your own tomorrow.

The More Knowledgeable Other

The person giving that help gets a name, too.

Vygotsky’s followers call them the more knowledgeable other, or the MKO.

And here’s what I love about that term.

It’s about skill, not age or title.

It could be a teacher.

It could be a coworker.

It could be your ten-year-old showing you how to fix the settings on your phone.

It could even be a good tutorial or a good video.

Hello, you’re watching one right now.

Scaffolding

Now, you’ve probably heard the word scaffolding in this context.

And I want to be honest with you about something.

Vygotsky himself never used that word.

Three researchers—Wood, Bruner, and Ross—introduced it in 1976 to describe how a helper supports a learner.

But it’s a beautiful metaphor.

Scaffolding on a building is temporary.

It goes up so the work can happen, and once the structure can stand on its own, it comes down.

Good teaching works the same way.

Lots of support at first, and then slowly less.

If the scaffolding never comes down, you don’t have a strong building.

You have a building that can’t stand without it.

Private Speech

There’s one more piece, and it’s one of my favorites.

Vygotsky noticed that young children talk to themselves while they play and solve problems.

They narrate.

“Okay, the blue one goes here. No, wait. It goes there.”

He called this private speech.

And he didn’t see it as cute noise.

He saw it as thinking out loud.

As children get older, that talking goes quiet and moves inside their heads, and it becomes what we think of as our inner voice.

Which means the voice in your head that says, “Okay, focus. What’s the next step?” started out as someone else’s voice helping you.

And if you talk yourself through assembling furniture, you didn’t outgrow private speech.

You just brought it back for a hard task.

This is a notebook moment.

Write this down:

The zone of proximal development is the gap between what a learner can do alone and what they can do with guidance from a more knowledgeable other.

Comparing Piaget and Vygotsky

Now, quick comparison.

Piaget asked, “What is this child ready for?”

Vygotsky asked, “What could this child do with the right help?”

And both of those are useful questions.

And Vygotsky’s inspector report is short but real.

It’s hard to measure a zone that shifts from task to task and person to person.

His theory leans heavily on language and conversation.

And who counts as a helpful, knowledgeable other looks different across cultures and communities.

But the big takeaway holds.

We don’t grow in isolation.

And that matters for the next part.

Because if thinking grows through other people, so does something else.

Piaget and Moral Development

Here’s a fun fact.

Piaget studied that, too.

In 1932, he published a book called The Moral Judgment of the Child.

And to research it, he did something wonderful.

He watched children play marbles.

He asked Swiss kids, “Who made the rules of this game? Can you change them?”

And he noticed something.

Younger children, roughly ages five to nine, treated rules like they were carved in stone.

Rules come from adults or from somewhere important, and you can’t change them.

Period.

Older children, around ten and up, saw rules differently.

Rules are agreements.

People made them, and people can change them if everyone agrees it’s fair.

He also told kids little stories.

In one, a boy accidentally breaks fifteen cups.

In another, a boy sneaks into the cupboard for jam and breaks one cup.

Then he asked which kid was naughtier.

Younger children said the first boy because more cups broke.

Older children said the second boy because he was doing something he wasn’t supposed to be doing.

They started to care about intentions, not just damage.

Which is a big shift.

And it means the way we think about morality changes as our thinking changes.

Kohlberg and Moral Reasoning

Piaget planted that seed, but a researcher named Lawrence Kohlberg grew a whole tree out of it.

Kohlberg started this work in the late 1950s for his doctoral research.

He followed a group of boys from Chicago, starting when they were around ten to sixteen years old.

And he kept checking in with them for about twenty years.

And to study how they thought about morality, he gave them dilemmas.

The Heinz Dilemma

The most famous one is the Heinz dilemma.

Here’s the story.

A woman is dying from a rare kind of cancer.

There’s one drug that might save her.

The pharmacist who invented it is charging way more than it costs to make.

Her husband, Heinz, tries everything.

He borrows money from everyone he knows, and he still can’t afford it.

He asks the pharmacist to lower the price or let him pay later.

The pharmacist says no.

So Heinz breaks into the pharmacy and steals the drug.

Should he have done that?

Now, here’s the thing.

Kohlberg did not care whether you said yes or no.

That’s the twist.

What he cared about was why.

Because two people can both say, “Yes, he should steal it,” and be reasoning in completely different ways.

And he found that the reasons people gave changed in a pattern as they got older.

He organized that pattern into three levels with two stages each.

Six stages total.

Let’s walk up the floors.

A Workplace Dilemma

And to make it real, instead of the Heinz story, let’s use something a lot of us have lived.

You find out that a coworker has been padding their timesheet.

Do you report it?

Level One: Preconventional Morality

Level one is called preconventional.

This is the ground floor, and it’s how young children reason.

Morality is about what happens to me.

Stage one is obedience and punishment.

“Don’t report it because you’ll get in trouble.”

Or, “It’s wrong because they could get fired.”

Right and wrong depend on whether you get punished.

Stage two is self-interest.

“I’ll keep quiet because maybe they’ll cover for me someday.”

It’s a trade.

What’s in it for me?

Level Two: Conventional Morality

Level two is conventional.

This is the middle of the house, and it’s where Kohlberg found most teens and adults reason most of the time.

Morality is about relationships and rules.

Stage three is the good-person stage.

“I don’t want to be the office snitch.”

Or, “A good friend wouldn’t turn them in.”

Here, being good means being seen as good by the people who matter to you.

Stage four is law and order.

“Rules are rules.”

“If everyone padded their timesheet, the whole system would fall apart.”

Now the focus is on the group, the institution, keeping society running.

Level Three: Postconventional Morality

Level three is postconventional.

This is the top floor, and the view here is different.

Now you’re not just asking, “What do the rules say?”

You’re asking, “What are the rules for?”

Stage five is the social contract.

“The timesheet policy exists to keep things fair for everybody, so I have to ask what’s fair here. Is this person taking advantage, or is the policy itself unfair?”

Rules are agreements that can be judged and changed.

And basic rights, like protecting a life, can outweigh them.

And stage six is universal principles.

Decisions based on self-chosen ethical principles like justice and human dignity, even when they conflict with the law.

Kohlberg himself found this stage was extremely rare.

A Notebook Moment

This is a big notebook moment.

Write down the three levels.

Preconventional: morality based on consequences to me.

Conventional: morality based on relationships and rules.

Postconventional: morality based on principles behind the rules.

Not a Scoreboard for Goodness

Now, I want to pause on something.

Because it would be really easy to hear this list and start ranking yourself or your family or the people in your comment section.

Please don’t.

These stages describe how someone reasons about a dilemma.

They’re not a scoreboard for how good a person is.

And people move around.

Stress, exhaustion, and fear can drop us right back down to the first floor.

Have you ever made a decision only because you were scared of getting in trouble?

Yeah, me too.

But the idea that reasons matter and that reasoning can grow is powerful.

The Building Inspector: Reviewing Kohlberg

Okay, time for the building inspector.

The first problem is who got studied.

Kohlberg’s original sample was boys.

Only boys.

And one of his own research assistants, Carol Gilligan, noticed.

In her 1982 book, In a Different Voice, she argued that his scoring system treated abstract justice as the peak of morality and that women often scored lower because they tended to lean on care, relationships, and responsibility to others.

Her point was not that women are less moral.

It was that the measuring stick was built for one kind of voice.

Culture and Moral Reasoning

The second problem is culture.

In 1985, researcher John Snarey reviewed studies from around the world and found that the top-floor reasoning—stages five and six—was rarely found in some traditional societies.

That doesn’t mean those communities were less moral.

It suggests Kohlberg’s top floors were built on Western ideas about individual rights and independence.

And many cultures put community and duty at the center and see that as the highest form of morality.

Reasoning Versus Behavior

And the third problem is this.

Knowing what’s right is not the same as doing it.

Kohlberg measured what people say in a hypothetical story.

But real life comes with real costs.

Habits. Pressure. Fear. Loyalty. Money.

Someone can reason beautifully about an ethical dilemma and still freeze when it’s their own job on the line.

So here’s how I’d use all of this.

Not as a set of rigid staircases that everyone climbs at the same speed.

More like maps.

Helpful maps that show us general patterns and that were drawn by real people in a real time and place with real blind spots.

Walking Back Through the House

So let’s walk back through the house one more time.

Piaget showed us the remodel.

Your mind builds and rebuilds its blueprints.

It fits new things in when it can, and it knocks down walls when it has to.

Vygotsky showed us the crew.

Nobody builds alone.

The teacher, the friend, the mentor, the tutorial that helps you do something you couldn’t do yet.

That’s where growth lives.

And Kohlberg showed us the floors.

How our reasoning about right and wrong can widen from “What happens to me?” to “What do the people around me expect?” to “What is actually fair, and for whom?”

Learning Across Adulthood

Here’s the part I hope you take with you.

None of this stopped when you turned eighteen or thirty or fifty.

Every time you change your mind, you’re accommodating.

Every time someone helps you do something you couldn’t quite do yet, you’re in your ZPD.

And every time you stop and ask yourself, “Wait, why do I believe this is right?” you are climbing a floor.

A Question for Your Notebook

So here’s a question for your notebook.

Think of one belief you changed as an adult.

What was the moment that shook it loose?

And who helped you get there?

Coming Up Next

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