The Story of Psychology (69 page)

All that, without any systematic training or degree in psychology.

Piaget amplified and modified his theory over the years, but we need look only at the final product.

Behaviorists held that development takes place through conditioning and imitation, hereditarians that it is the automatic result of maturation. Piaget differed with both. He held that mental development requires both experience and maturation but is the result of an ever-changing interaction between organism and environment. In that interaction the mind adapts to an experience, is then able to interact in a different fashion with the environment, and adapts still further, undergoing a series of metamorphoses until it reaches the adult state. An infant’s digestive system can at first handle only milk, but later, having developed thanks to the milk, can digest solid food. In similar fashion, the intellect is at first a simple structure that can absorb and utilize only simple experiences but, nourished by them, becomes more advanced, competent, and able to handle more complex ones.

A four-month-old baby, according to Piaget’s research, does not recognize that the toy is under Piaget’s beret; at that stage of mental development, the mind has only current perceptions, not stored images, and a concealed object is as good as nonexistent. But by the latter part of the first year, after accidentally finding the toy under the beret a few times, the baby has modified the reaction to seeing it covered over.

In another classic experiment, the child who has not yet learned to count says that six buttons spaced out in a line are “more” than six buttons
bunched together in a line. When he learns to count, he discovers otherwise and his mind’s way of handling such perceptions is transformed.

Both experiments exemplify the two crucial processes of mental development in Piaget’s theory:
assimilation
and
accommodation.
The child assimilates the experience of counting the buttons—ingests it, so to speak, as if it were like previous experiences when what looked bigger was indeed bigger. But the new experience produced by counting is discordant with that assumption; the mind, to restore its equilibrium, accommodates (reorganizes) sufficiently to incorporate the new experience, and from then on sees and interprets sets of objects in a way better adapted to reality.
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Piaget once recounted the story of a mathematician friend that nicely illustrates how the assimilation of new information leads to accommodation and new thinking. The friend, as a small child, was counting pebbles one day. He lined them up, counted from left to right, and got ten. Then, to see what he would get by counting in the other direction, he recounted them from right to left—and was amazed: he still got ten. Inventively, he then arranged them in a circle and counted them: ten, of course. He recounted, going around the circle the other way: ten! “He discovered here,” Piaget commented, “what is known in mathematics as commutativity; that is, the sum is independent of the order.”
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Such mental development does not take place smoothly and continuously. From time to time, the accumulation of small changes such as the discovery of commutativity brings about a relatively abrupt shift to a different stage of thinking. The notion that the human psyche develops stage by stage was not original with Piaget—it had been suggested earlier by other psychologists—but Piaget was the first to identify and describe the stages on the basis of a wealth of observational and experimental evidence. The four major stages in Piaget’s theory (there are many substages) are:

The ages are only averages; Piaget was well aware that there are individual differences. But he said that the sequence was invariant; each stage is the necessary foundation of the succeeding one.

This is what takes place in each (some of the following findings have been modified by later research, as we will shortly see):
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Sensorimotor (birth to 18–24 months):
At first infants are aware only of their sensations and do not connect them with external objects. They do not even connect the images of their hands with the sensations of their hands moving, and only gradually, through trial and error, discover how to make their reaching for a toy coincide with what they see.

Even when their movements become more purposeful and accurate, they have no sense of what the objects around them are like or how those things will respond to their actions. So they experiment: they suck, shake, bang, hit, or throw objects, thereby acquiring new knowledge that leads to more intelligent and purposeful actions.

From such experiences, and with the help of the growing power of memory (in part due to continuing maturation of the brain), children begin to have a store of mental images. This is why they realize, in the latter quarter of the first year, that a hidden object still exists, even though the perception of it is gone. Piaget called this the attainment of “object permanence.”

Toward the end of this stage, children begin to use their stored images and information to solve problems involving physical objects; they think about what might happen, instead of relying solely on manipulating things. Piaget, as a young father, proudly reported an episode of such thinking by his daughter Lucienne, who was sixteen months old. While playing with her, he put a watch chain in an empty matchbox, which he carefully left slightly open. He handed the matchbox to Lucienne, who had not been aware of his opening and closing it and had not seen him put the watch chain in it. She had only two “schemes” (learned ways of dealing with the situation): turning the box upside down to dump out its contents, and pushing her fingers in the slit to bring out the chain. She tried the second procedure first, groping to reach the chain, but was unable to. Then came a pause, during which Lucienne did something odd and noteworthy; as Piaget later reported the event:

Children also begin, at this time, to think about how to effect desired social consequences. Again Piaget reports his observation of one of his children:

The child is acquiring a rudimentary ability to imagine or predict the results of certain simple actions and to conduct trial-and-error experiments in the mind. Henceforth, says Piaget, intellectual development proceeds “in the conceptual-symbolic rather than purely sensorimotor arena.”
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Preoperational (18–24 months to 7 years):
Now the child rapidly acquires images, concepts, and words and becomes better able to talk and think about external objects and events in symbolic terms. The two-year-old shoves a wooden block around the floor and makes the sounds of a truck; the three-year-old pretends to drink out of an empty toy cup. At first, the child learning to talk regards things and their names as one and the same (the two-year-old sees a bird and says “Bird!” and if an adult uses the word “bird” the child says, “Where bird?”), but eventually learns that the word is a symbol, detachable from what it stands for. From then on, he or she is able to talk and think about absent things and past or future events.
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But the child’s internal representation of the world is still primitive, lacking such organizing concepts as causality, quantity, time, reversibility, comparison, and perspective. The child cannot perform mental operations involving these ideas; hence it is the “preoperational” stage. (By “operation” Piaget meant any mental routine that transforms information for some purpose. Classifying, subdividing, recognizing the parts in a whole, and counting are typical operations.) This is why the five-year-old thinks that six buttons spread out are more than six closely bunched, and water transferred to a tall thin glass is more than it was in a wide shallow glass. Even when children learn to count, for some time they do not grasp that 2×3 has to equal 3×2. Shown a bunch of flowers,
most of which are yellow, and asked, “Are there more flowers or more yellow flowers?” they answer “Yellow.”

The preoperational child is also “egocentric” (as was the sensorimotor child), a term Piaget defined as incapable of imagining how things look from another perspective. Piaget would show four- to six-year-olds a model of three mountains, put a little doll in a particular place amidst the mountains, display a set of photographs of the mountains taken from different positions, and ask the children which one showed what the doll was now seeing. The children always chose the view they themselves saw. Similarly, he reported, preoperational children have trouble imagining what other people are thinking, and often speak without realizing that the other person is unfamiliar with what they are talking about.

Concrete operations (7 to 12 years):
By seven or thereabouts, children shift to a distinctly new and more competent level of thinking. Now they can perform such operations as counting and classifying, and can understand and think about relationships. Where the preoperational child knows the word “brother” but cannot say what a brother is and knows what “big” is but cannot say which is the bigger of two big things, the operational child can deal with both.
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Mentally reversing a procedure is another operation. When a child can imagine pouring water back from the tall thin container into the original one, he acquires the concept of reversibility and with it that of “conservation,” the recognition that quantity does not change when shape does.

Children in this stage also become aware that events outside themselves have causes outside themselves. Preoperational children will say it gets dark at night because we go to sleep; concrete-operational children say it is because the sun sets. They are also better able to imagine how things look from another perspective, and how other people think and feel. They can thus mentally manipulate symbols as if they were the things they refer to—but only symbols of physical objects and actions, not abstract ideas or logical processes. Deductive reasoning eludes them. Give them the first two propositions of a syllogism and they are not consistently able, if able at all, to draw the right conclusion.

Nor can they proceed systematically when tackling a problem with several variables. One of Piaget’s most productive tests was his pendulum problem. He would show a child a weight hanging from a string and demonstrate how to vary the length of the string, the amount of weight suspended by it, how to release the weight from different heights,
and how to push it with different degrees of force. Then he would ask the child to figure out what factor or factors (length, weight, height, and force, singly or together) affected the pendulum’s rate of swinging. Pre-operational children made no plan of action; they tried different things at random, often varying several factors at once, making many incorrect observations, and reaching wrong conclusions. Operational children, though more systematic and accurate, still made frequent mistakes owing to illogical thinking. One ten-year-old boy tried changing the length of the string and concluded correctly that a pendulum swings slower when the string is longer. Then he compared the effect of a hundred-gram weight on a long string against that of a fifty-gram weight on a short string and concluded incorrectly that the pendulum also swings slower when the weight is greater.
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Formal operations (12 and up):
In the final stage of development, children become capable of thinking about abstract relationships, like ratio and probability. They grasp syllogistic reasoning, cope with algebra, and begin to comprehend the elements of scientific thought and methodology. They can formulate hypotheses, concoct theories, and systematically examine the possibilities in a puzzle, mystery, or scientific problem. They play a game like Twenty Questions methodically, starting with broad questions and narrowing down the field of possibilities; until this stage their questions skipped from broad areas to narrow ones and back to broad ones, or overlapped, or were repetitive.

More important, they can now think not only about the concrete world but about possibilities, probabilities, and improbabilities, about the future, about justice, and values. As Piaget and his longtime collaborator, Bärbel Inhelder, say:

Jerome Kagan has called Piaget’s analysis of the fundamentally new cognitive powers of adolescence “one of the most original ideas in any theory of human nature” and the source of “insights about adolescent behavior that challenge traditional explanations.” For one thing, it helps
us understand the rise in the suicide rate in the teen years: the ability to think about hypothetical situations and know when one has exhausted all solution possibilities enables the adolescent to tell himself (rightly or wrongly) that he has tried or examined all ways of solving some personal problem and that none will work. For another, the ability to perceive inconsistencies within his own beliefs or those he is told to believe helps explain the rebelliousness, anger, and anxiety of the adolescent. Among the common and deeply troubling inconsistencies: conflicting values about teenage sex (it is immoral and risky, yet to abstain may seem “hung up” and abnormal); conflicting perceptions of the teenager’s relation to his parents (he wants and needs their support but also wants to be independent); and so on.
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