Jean Piaget

It is with children that we have the best chance of studying the development of logical knowledge, mathematical knowledge, physical knowledge, and so forth.

Knowing reality means constructing systems of transformations that correspond, more or less adequately, to reality.

The goal of education is not to increase the amount of knowledge but to create the possibilities for a child to invent and discover, to create men who are capable of doing new things.

To express the same idea in still another way, I think that human knowledge is essentially active.

This means that no single logic is strong enough to support the total construction of human knowledge.

On the one hand, there are individual actions such as throwing, pushing, touching, rubbing. It is these individual actions that give rise most of the time to abstraction from objects.

All morality consists in a system of rules, and the essence of all morality is to be sought for in the respect which the individual acquires for these rules.

Children's games constitute the most admirable social institutions. The game of marbles, for instance, as played by boys, contains an extremely complex system of rules - that is to say, a code of laws, a jurisprudence of its own.

Everyone knows that at the age of 11-12, children have a marked impulse to form themselves into groups and that the respect paid to the rules and regulations of their play constitutes an important feature of this social life.

Scientific thought, then, is not momentary; it is not a static instance; it is a process.

Scientific knowledge is in perpetual evolution; it finds itself changed from one day to the next.