Jean Piaget’s landmark studies of cognitive development rocked the psychological world.
His work suggested that children don’t grasp basic logic until they are approximately seven years old (Inhelder and Piaget 1958).
Other experiments, pioneered by Heinz Wimmer and Josef Perner, suggested that little kids can’t work out what goes on in other people’s minds.
According to this research, children lack a theory of mind--the ability to reflect on what other people think or believe--until they are four years old (Wimmer and Perner 1983).
But are kids as clueless as these studies made them appear?
There are alternative explanations.
In some cases, children may be puzzled when adults ask obvious questions. Kids might change their answers to reflect what they think the adults want them to say.
In other cases, experimental tasks might bombard kids with too many extraneous details, making it hard for children to stay focused on the essential points of the test.
And here is another intriguing theory: All people, even highly educated adults, experience misleading intuitions and cognitive biases. Getting the right answer depends--in part--on being able to ignore those intuitions when other information tells us they are wrong.
So perhaps kids seem illogical because they have more trouble turning off their misleading intuitions.
The evidence? Consider first the weird things kids that say during tests of cognitive development.
Three crazy mistakes that young children make
Classic experiments show that young children regularly commit bizarre errors like these:
1. More red flowers or more flowers?
An adult shows a child a bunch of flowers. Four are red, two are white. The adult asks,
“Are there more red flowers or more flowers?
Kids younger than six usually answer “There are more red flowers.”
2. Can other people possess false beliefs?
A child watches a puppet show about Maxi and his mother.
Maxi sees his mother put some chocolate in a blue cupboard. Next, Maxi goes out to play.
While Max is gone, his mother uses some of the chocolate to make a cake. Then she puts the remaining chocolate in a new location – a green cupboard.
Then the puppeteer asks the child:
“When Maxi comes back, where will he look for the chocolate?”
Before the age of four, most kids say that Maxi will look for the chocolate in the new location, not the blue cupboard.
3. Does merely moving objects around change how many there are?
A four- or five-year-old examines two identical rows of coins. He notes that each row contains the same number of coins. But when an adult alters the top row--pushing together the coins so that the row appears shorter--the child amends his assessment.
Now he says that the top row contains fewer coins.
What’s going on?
These outcomes have been replicated in populations around the world. What’s going on?
Do the errors reflect limitations imposed by cognitive development? Or does a child's performance depend on the ways we test her?
The answer seems to be a little of both.
Let’s start with ways we test kids.
When interpreting questions, kids take context into account
It’s no surprise that children are sensitive to the social context of language--what linguists call “pragmatics.”
When adults ask kids weird questions—as they often do in experiments designed to test cognitive development—kids may wonder why.
Misunderstandings about logic....or about the adult questioner's meaning?
Consider the flower task. It’s from an experiment designed by Jean Piaget, and it’s supposed to test whether or not kids understand class inclusion or set theory, i.e., the idea that all the members of one set (red flowers) can belong to another, more inclusive set (flowers).
But the question about flowers—“Are there more red flowers, or more flowers?” is weird. Real people don’t talk that way.
So maybe, the child reasons, the adult means something different when she speaks of “flowers.” Maybe the adult is really asking me to compare the red flowers with the white flowers.
Might this explain the error? One study changed the wording of the question to this:
“Here is a bunch of grapes. There are green grapes and there are purple grapes, and this is the bunch. Who would have something more to eat, someone who ate the green grapes or someone who ate the bunch?”
This is a more natural way of asking the question. And it seems to make a difference.
When kids were given this “natural language” version of the test, they did significantly better (Markman and Seibert 1976).
More recently, Usha Goswami and Sabina Pauen designed yet another way to test kids (Goswami and Pauen 2005).
In their experiment, they asked kids to “create a family” using animal toys. This required that kids recognize one inclusive category (the species) and two subcategories (big and small animals of the same species).
Next, the kids were asked to extend the idea to inanimate objects, like blocks and balloons. The children, who were four- and five-year-olds, performed much better on this task than on the original, Piagetian flower task.
“Theory of Mind” errors
Remember the puppet show about Maxi and his mother? That scenario is designed to test a child’s “theory of mind” skills.
Does the child assume that his own thoughts, beliefs, and desires are shared universally by everyone? Or does he understand that other people have minds of their own--and may believe things that he himself knows to be false?
As noted above, kids younger than four years tend to have trouble with the hidden chocolate problem. When asked where an ignorant character will look for the chocolate, the kids give the wrong answer. They claim that the character will look where the chocolate really is, not where the character should believe it to be.
This might indicate that two- and three-year-olds don’t attribute mental states to other people. A pretty disturbing thought!
But other research suggests different story. As I’ll explain in a future article, recent experiments suggest that even 15-month-old babies understand something about false beliefs (Onishi and Baillargeon 2005; Perner and Rossler 2012).
So why do young children fail the Maxi false belief task?
Michael Siegal and Katherine Beattie (1991) wondered if kids misunderstood the question. Maybe kids thought they were being asked where Maxi should look for the chocolate.
So the researchers changed the question. Instead of asking “Where will Maxi look for the chocolate?” they asked
“Where will Maxi look first for the chocolate?”
With this new wording, even three-year-olds tended to get the right answer most of the time.
These results are consistent with another explanation, too. Maybe the original puppet show was just too complex, and kids got distracted by extraneous details.
Paula Rubio-Fernández and Bart Geurts argue that several features of the show may have prevented kids from tracking Maxi's perspective. It's not clear at the beginning who the protagonist was, and Maxi left the scene for much of the story while his mother made a cake. Also, at the end, "the experimenter switched roles from puppeteer to interviewer to spring his question on the unsuspecting child." Any of these details might disrupt a young child's attempt to keep track of what Maxi believes.
To test their explanation, Rubio-Fernández and Geurts created a simpler puppet show with fewer distractions. They also made sure that kids were paying attention to the fact that the protagonist couldn't see what was going on when the treat was moved. Under these conditions, 80% of three-year-olds got the right answer when asked what the protagonist would do next (Rubio-Fernández and Geurts 2012).
What about the last example—the one with the two rows of coins?
This is another task developed by Piaget, and it’s supposed to test a child’s understanding of conservation, the idea that some properties (like the number of items in a set) don’t change because we merely move things around.
A principle of physics? Yes. But it’s about basic reasoning, too. As David Elkind and Eva Schoenfeld (1972) noted, the conservation task requires us to use that fundamental tool of deduction, the transitive inference:
1. Row 1 = Row 2
2. Row 1 = Row 1A (in which where the coins are pushed closer together)
3. Row 1A = Row 2
So it’s not just that kids haven’t worked out the rules of our physical universe. There seems to be a failure to apply logic.
But social context may play a role here, too.
Imagine you’re the child being tested.
You’ve just told the adult that both rows contain the same number of coins.
Next, the adult takes the coins in the first row and changes the spacing between them. Then she asks you the same question again—are there “more, less, or the same in each row?”
What are you to think?
Ordinarily, you’d assume that the number hasn’t changed. But why would this authority figure ask such an obvious question?
Maybe--for some unknowable reason--she wants or expects you to change your original answer. So you do.
Could this explain why many kindergarteners have failed the conservation task? It might explain part of the phenomenon.
James McGarrigle and Margaret Donaldson gave the classic conservation task a tweak. After the child inspected the two rows and acknowledged that they were equivalent, the experiment was “interrupted” by a “naughty” teddy bear who shifted the coins. The adult scolded the bear and asked the question again.
In this scenario, even four-year-olds tended to get the right answer (McGarricle and Donaldson 1975).
These results have been questioned by some researchers. Maybe the teddy bear distracted kids so much that they didn't bother to rethink their answers.
And if you look at the demonstration video (which shows several standard Piagetian conservation tasks), perhaps you can see why some people don't believe that kids are in conflict.
I'm not an expert reader of body language. But to my untrained eye, these girls seem pretty sure of themselves.
On the other hand, they also seem very eager to please!
Do they really believe the quantities have changed? Or are they convinced that the woman wants them to change their answers?
So does social context explain all the errors?
No. The context of language--pragmatics--is an important aspect of any experiment that involves communication. And today’s researchers pay close attention to the ways that pragmatics might influence children’s behavior.
But pragmatics can’t explain away all the mistakes we see young children make:
• Experience helps, too. A study of first graders suggests that kids benefit when they are explicitly trained to solve classification problems (Pasnak et al 2006)—a finding that supports the overall notion that logic and critical thinking can be taught.
• As I’ll explain in a future article, theory of mind skills also develop over time. Even adults have trouble with certain versions of the false-belief task (Birch and Bloom 2007).
And what about conservation?
Outside of the psychologist’s laboratory, kids commit conservation errors in a variety of everyday contexts.
It’s pretty clear they are relying on certain rules-of-thumb, like
“If there is a row of objects, use the length of that row to estimate quantity.”
This is usually a pretty good way to estimate, which is why many adults use the rule when deciding which line to stand in at the supermarket.
The problem is that kids fail to selectively ignore the rule when they have other, better information.
That’s a particularly intriguing idea. As I’ll discuss in a future article, researchers are accumulating evidence that young children--even babies--understand more than their behavior implies. They make more mistakes, however, and that’s because they have a tougher time “turning off” their misleading intuitions.
For instance, consider the Stroop effect, which shows that people take longer to answer questions when those questions contain distracting elements.
Even when you know that the distractions are irrelevant, some part of your mind is captivated by them.
Too see what I mean, try answering quickly: Which of these animals is larger in real life?
Because the rabbit looks larger, part of your mind wants to answer “rabbit.” To get the right answer, you must inhibit that impulse, which takes extra effort and time.
Kids are slower at these sorts of tasks, and brain research suggests why. For kids, the brain activity associated with the incorrect response (e.g., the rabbit) is stronger and longer-lasting than it is for adults (Szucs et al 2009).
The kids really do know that elephants are bigger than rabbits. But they have more trouble inhibiting the wrong answer.
Their internal censor--the executive function that stops us from blurting out silly things--isn’t as powerful.
References: Cognitive development, pragmatics, and inhibition
Birch SAJ and Bloom P. 2007. The curse of knowledge in reasoning about false beliefs. Psychological Science 18(5): 382-386.
Elkind D and Schoenfeld E. 1972. Identity and equivalence conservation at two age levels. Developmental Psychology 6: 529-533.
Goswami U and Pauen S. 2005. The effects of a "family" analogy on class inclusion reasoning by young children. Swiss Journal of Psychology, 64, 115-124.
Inhelder B and Piaget J. 1958. The Growth of Logical Thinking from Childhood to Adolescence. New York: Basic Books.
Markman E and Seibert J. 1976. Classes and collections: internal organization and resulting holistic properties. Cognitive Psychology 8: 561-577.
McGarrigle J and Donaldson M. 1975. Conservation accidents. Cognition 3: 341-350.
Moore C and Frye D. 1986. The effect of experimenter's intention on the child's understanding of conservation. Cognition. 22(3):283-98.
Onishi KH and Baillargeon R. 2005. Do 15-month-old infants understand false beliefs? Science 308: 255-258.
Perner J and Roessler J. 2012. From infants' to children's appreciation of belief. Trends Cogn Sci. 16(10):519-25.
Rubio-Fernández P and Geurts B. 2012. How to Pass the False-Belief Task Before Your Fourth Psychol Sci. 2012 Nov 21. [Epub ahead of print].
Siegel M and Beattie D. 1991. Where to look first for children’s knowledge of false belief. Cognition 38: 1-12.
Stroop JR. 1935. Studies of interference in serial verbal reactions. J. Exp. Psychol. 18:643-662.
Szücs D, Soltész F, Bryce D and Whitebread, D. 2009. Real-time tracking of motor response activation and response competition in a Stroop task in young children: A lateralized readiness potential study, Journal of Cognitive Neuroscience 21(11): 2195-2206.
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