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

Intelligence is what you use when you don't know what to do.

How can we, with our adult minds, know what will be interesting? If you follow the child...you can find out something new.

The principle goal of education in the schools should be creating men and women who are capable of doing new things, not simply repeating what other generations have done.

In other words, knowledge of the external world begins with an immediate utilisation of things, whereas knowledge of self is stopped by this purely practical and utilitarian contact.

Our problem, from the point of view of psychology and from the point of view of genetic epistemology, is to explain how the transition is made from a lower level of knowledge to a level that is judged to be higher.

Reflective abstraction, however, is based not on individual actions but on coordinated actions.