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.

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

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

The current state of knowledge is a moment in history, changing just as rapidly as the state of knowledge in the past has ever changed and, in many instances, more rapidly.

As you know, Bergson pointed out that there is no such thing as disorder but rather two sorts of order, geometric and living.

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.

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.