The more the schemata are differentiated, the smaller the gap between the new and the familiar becomes, so that novelty, instead of constituting an annoyance avoided by the subject, becomes a problem and invites searching.

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.

It was while teaching philosophy that I saw how easily one can say ... what one wants to say. ... In fact, I became particularly aware if the dangers of speculation ... It's so much easier than digging out the facts. You sit in your office and build a system. But with my training in biology, I felt this kind of undertaking precarious.

I could not think without writing.

We learn more when we are compelled to invent.

What we see changes what we know. What we know changes what we see.

When you teach a child something you take away forever his chance of discovering it for himself.