We learn more when we are compelled to invent.

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

During the earliest stages the child perceives things like a solipsist who is unaware of himself as subject and is familiar only with his own actions.

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.

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

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 for himself will remain with him visible for the rest of his life.

Logical positivists have never taken psychology into account in their epistemology, but they affirm that logical beings and mathematical beings are nothing but linguistic structures.