Logic and mathematics are nothing but specialised linguistic structures.
Scientific knowledge is in perpetual evolution; it finds itself changed from one day to the next.
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.
Logical activity is not the whole of intelligence. One can be intelligent without being particularly logical.
It is with children that we have the best chance of studying the development of logical knowledge, mathematical knowledge, physical knowledge, and so forth.
Egocentrism appears to us as a form of behavior intermediate between purely individual and socialized behavior.