In fact, objects are known only through the subject, while the subject can know himself or her- self only by acting on objects materially and men- ta… - Jean Piaget

In fact, objects are known only through the subject, while the subject can know himself or her- self only by acting on objects materially and mentally. Indeed, if objects are innumerable and science indefinitely diverse, all knowledge of the subject brings us back to psychology, the science of the subject and the subject's actions.

Children should be able to do their own experimenting and their own research. Teachers, of course, can guide them by providing appropriate materials, but the essential thing is that in order for a child to understand something, he must construct it himself, he must re-invent it. Every time we teach a child something, we keep him from inventing it himself. On the other hand that which we allow him to discover by himself will remain with him visibly for the rest of his life.

A child’s first geometrical discoveries are topological. If you ask him to copy a square or a triangle, he draws a closed circle.

A second prefatory question faces us: that of society and the individual. We have sought to contrast the child and the civilized adult on the ground of their respective social attitudes. The baby (at the stage of motor intelligence) is asocial, the egocentric child is subject to external constraint but has little capacity for cooperation, the civilized adult of to-day presents the essential character of cooperation between differentiated personalities who regard each other as equals. There are therefore three types of behavior: motor behavior, egocentric behavior (with external constraint), and cooperation. And to these three types of social behavior there correspond three types of rules: motor rules, rules due to unilateral respect, and rules due to mutual respect. But here again, one must beware of laying down the law: for things are motor, individual and social all at once. As we shall have occasion to show, rules of cooperation are in some respects the outcome of the rules of coercion and of the motor rules. On the other hand, coercion is applied during the first days of an infant's life, and the earliest social relations contain the germs of cooperation. Here again, it is not so much a question of these successive features themselves as of the proportions in which they are present. Moreover, the way in which conscious realization and the time-lag from one level to another come into play is a further bar to our arranging these phenomena in a strict sequence, as though they made a single appearance and then disappeared from the scene once and for all.