The more we try to improve our schools, the heavier the teaching task becomes; and the better our teaching methods the more difficult they are to apply.

It is with children that we have the best chance of studying the development of logical knowledge, mathematical knowledge, physical knowledge, and so forth.

Teaching means creating situations where structures can be discovered.

Play is the answer to how anything new comes about.

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.

How much more precious is a little humanity than all the rules in the world.

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.