Radical constructivism was initially formulated by Ernst von Glasersfeld.
Radical constructivists do not speak of creating reality, but of
constructing reality. What is the difference?
"Creating reality" ultimately means creating everything, without exception. "Constructing reality"
means interpreting external "disturbances" and thus shaping effects.
Thus the constructivist has the lesser claim, but at the price of
inconsistency. He cannot avoid including an external cause of effect that essentially
determines his construction. In principle, however, he cannot and does not want
to know by what this obviously pre-structured effect is exerted. What is
important is only what is useful in the context of one's own life, whereby
"usefulness" is equally constructed and thus co-determined by this
external something, and so on.
Instead, he might well admit that there is an external reality, the effect
of which he is only further constructing. But he would not be saying anything
essentially new. And once he admits its pre-structuring, he might as well go on
to ask what else there is to "pre-recognize". And with that, he
abolishes the radicality of constructivism.
