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.

— Jean Piaget

During the first few months of an infant's life, its manner of taking the breast, of laying its head on the pillow, etc., becomes crystallized into imperative habits. This is why education must begin in the cradle.

— Jean Piaget

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.

— Jean Piaget

From this time on, the universe is built up into an aggregate of permanent objects connected by causal relations that are independent of the subject and are placed in objective space and time.

— Jean Piaget

I could not think without writing.

— Jean Piaget

I have always detested any departure from reality, an attitude which I relate to my mother's poor mental health.

— Jean Piaget

Intelligence is what you use when you don't know what to do: when neither innateness nor learning has prepared you for the particular situation.

— 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.

— Jean Piaget

Logical activity is not the whole of intelligence. One can be intelligent without being particularly logical.

— Jean Piaget

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.

— Jean Piaget