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Twenty years ago, a pair of researchers in England reported on a series of experiments in which they showed that very young children could, in the context of play, solve logic problems that they seemed unable to solve in a serious context.
The problems they used were syllogisms, the classic type of logic problem described originally by Aristotle. A syllogism requires a person to combine the information in two premises to decide if a particular conclusion is true, false, or indeterminate (cannot be determined from the premises). Syllogisms are generally easy when the premises coincide with concrete reality, but are more difficult when the premises are counterfactual (contradictions to reality). The prevailing belief at the time that the British researchers conducted these experiments was that the ability to solve counterfactual syllogisms depends on a type of reasoning that is completely lacking in young children.
Here is an example of the kind of counterfactual syllogism that the researchers used:
All cats bark (major premise).
Muffins is a cat (minor premise).
Does muffins bark?
Previous research--including research by the famous Swiss developmental psychologist Jean Piaget--had shown that children under about 10 or 11 years old regularly fail to solve such syllogisms correctly (that is, they fail to give answers that logicians take as the correct answers). When the British researchers put syllogisms like this to young children in a serious tone of voice, the children answered as Piaget and others would expect. They said things like, "No, cats go meow, they don't bark." They acted as if they were unable to think about a premise that did not fit with their real-world experiences. But, when the researchers presented the same problems in a playful tone of voice, using words that made it clear that they were talking about a pretend world, children as young as 4 years old solved the problems easily, and even many 2-year-olds solved them![1] They said, "Yes, Muffins barks."
Think of it: Four-year-olds in play easily solved logic problems that they were not supposed to be able to solve until they were about 10 or 11 years old!
How the playful state led young children to the "correct" answers to syllogisms
Piaget and other philosophers and psychologists of his time generally drew a sharp distinction between two kinds of reasoning----concrete reasoning and abstract reasoning (which Piaget called hypothetico-deductive reasoning). They argued that the first kind of reasoning depends on direct, concrete, previous experience with the conditions that are being thought about and the second kind depends on formal logic that has a mathematical foundation and can be applied to problems regardless of the person's experience, or lack of experience, with the concrete substance of the problems. Some philosophers and psychologists argued, further, that concrete reasoning develops naturally in nearly all people while abstract reasoning requires special training of the type found in Western schools. Others, including Piaget, contended that abstract reasoning does develop naturally, but typically does not emerge in children until they are about 11 years old. According to Piaget, young children could not solve counterfactual syllogisms, because they lacked the capacity for abstract reasoning. But Piaget was wrong.
Today, many if not most developmental and cognitive psychologists, myself included, reject the distinction between concrete and abstract reasoning. We argue that so-called abstract reasoning occurs through mental transformations that turn what at first appears to be an abstract problem into a concrete problem--that is, into a problem that is very similar to a problem that the person has previously encountered and solved in the real world. Those mental transformations involve imagination, and even young children are capable of them. From this point of view, all human reasoning is concrete; it is just that some problems involve a greater use of imagination than do others in order to put them into concrete form.[2]
Human play, by definition, involves imagination (see my Nov. 19, 2008, posting). Play naturally leads us to think of things as they might be rather than just as they currently are. In the playful state of mind it is easy for anyone to imagine and think about a world in which people can fly, in which time machines can transport us to the past, or in which all cats bark. Young children are masters of play, so it is no surprise that they can solve counterfactual syllogisms in the context of play.
Why can 11-year-olds solve counterfactual syllogisms in a serious context while 4-year-olds require a playful context? I think the answer has little to do with age differences in reasoning ability and much to do with differences in understanding of the researchers' purpose in asking the questions. Four-year-olds misinterpret the researchers' purpose. They believe that when adults ask them questions in a serious tone of voice, they want serious answers, answers that have to do with truth about the real world. So, they respond accordingly--"Cats don't bark." On the other hand, 11-year-olds, especially 11-year-olds who have been to school, recognize that the question is not about reality but is a test of logic, so they accept the counterfactual premise and give the answer that the researcher wants. They realize that this is a game that the researcher is playing, which has to do with a pretend world and not with the real world. Four-year-olds recognize the game-like quality only when the researcher makes it clear, through tone of voice and wording, that it is a game.
Researchers have found that unschooled adults in other cultures "fail" counterfactual syllogisms, just as young children in our culture do. In the past, this has been interpreted as evidence that schooling is necessary for the development of abstract thinking. But my guess is that those adults "fail" on such problems for the same reason that young children in our culture do; they misinterpret the intent of the questions. I bet if researchers put the same problems to unschooled adults in a playful mode, they too would easily solve them.
My overriding point here is that play automatically induces hypothetical reasoning. It leads us to think about pretend worlds, where anything is possible, and to reason about those possibilities, rather than to limit our thoughts just to things that are true in the immediate here and now. In this way play promotes the kind of thought that is crucial not just to all of theoretical science but to all planning about the future, in which we must imagine possible events and think about how we might deal with those events.
Please do not draw the wrong conclusion from this little discussion. I am not arguing that it is a good idea, educationally, to induce playful states deliberately in children in order to improve their reasoning, as the researchers did in their experiment. Children play naturally, and it is through natural play that children practice reasoning. Children who are manipulated into play by teachers who think that this will improve their reasoning will soon learn to resist the manipulations. Play, in the long run, is only play if it is self-chosen and self-directed. Children practice reasoning in their own ways, through their own self-chosen play; we can't do it for them and shouldn't try. All we need to do, as I have argued in previous installments (e.g. Sept. 30, 2008, posting), is to provide places where children can play and explore safely and naturally, with others in age-mixed groups. They will take care of the rest.
How playfulness allowed college students to solve a classic insight problem
Here is another example of an experiment showing the power of a playful mood to improve problem solving. In this case the subjects were college students and the problem was a classic insight problem, called candle problem. In this task, subjects are given a small candle, a book of matches, and a box of tacks and are asked to attach the candle to a bulletin board in such a way that the candle can be lit and will burn properly. They are allowed to use no objects other than those they were given. The trick to solving the problem is to realize that the tacks can be dumped out of the box that holds them and the box can then be tacked to the bulletin board and used as a shelf on which to mount the candle. In the typical test situation, very few people solve this problem. They fail to see that the tack box can be used for something other than a container for tacks.
In the experiment, some subjects were exposed to a slapstick comedy film for a short period just before being presented with the candle problem, while others saw a serious film and still others saw no film. The result was that watching a slapstick film greatly increased the percentage of subjects who solved the problem.[3] The researchers' interpretation was that a happy mood broadens thought and leads to insight. My own interpretation is similar but emphasizes the role of play. I think the slapstick comedy put the subjects in a playful state of mind and that playfulness, not just happiness itself, led to the broadened way of thinking. In play, we regularly view objects and information in new ways. In a serious state of mind, whether we are happy or not, we fail to imagine that a tack box might be a shelf; but in a playful state such imagination comes easily. In play we regularly imagine objects to be other than what they were originally designed for. In play a broom can be a horse, a thimble can be a bishop, and a tack box can easily be a shelf.
One of the main purposes of play in our species, I think, is to promote our use of imagination to solve problems. We appear to be the only animal that thinks in imaginative ways. Imagination provides the foundation for our inventiveness, our creativity, and our ability to plan for the future. I believe that our huge capacity and desire for play came about, in evolution, partly to promote our capacities to invent, create, and plan. When we allow children ample opportunities for real play, we are providing them with opportunities to exercise and develop those capacities. When we allow ourselves to take a playful attitude in our work and domestic life, we are providing ourselves with a context for solving problems that might otherwise be intractable.
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References
1. Dias, M. G., & Harris, P. L. (1988). The effect of make-believe play on deductive reasoning. British Journal of Developmental Psychology, 6, 207-221.
2. I elaborate on the idea that "abstract" thought is really just concrete thought coupled with imagination in my textbook, Psychology, 5th edition (2007), pp 348-351.
3. Isen, A. M., Daubman, K. A., & Nosicki, G. P. (1987). Positive affect facilitates creative problem solving. Journal of Personality and Social Psychology, 52, 1122-1131.
