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.

The most developed science remains a continual becoming

What is desired is that the teacher ceased being a lecturer, satisfied with transmitting ready-made solutions. His role should rather be that of a mentor stimulating initiative and research.

Scientific knowledge is in perpetual evolution; it finds itself changed from one day to the next.

Equilibrium is the profoundest tendency of all human activity.

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.

Scientific thought, then, is not momentary; it is not a static instance; it is a process.