ABSTRACT
I would like to bring the book full circle, returning to two points raised by Ernst von Glasersfeld in his opening chapter. These are the fact that radical constructivism is misinterpreted so persistently by its critics, and the need for radical constructivism to provide a clear model of social interaction. I return to these points not only to give the book a particular rhetorical structure, but because they penetrate many of the controversies both internal to mathematics and science education and at the boundaries of radical constructivism. At the same time, I will point out the importance of conceptual analysis in Glasersfeld’s method and urge more people to use it in mathematics and science education.
