ABSTRACT
It is not possible within the scope of this chapter to mount a full-scale philosophical defence of radical constructivism. What is possible is an attack from the radical constructivist point of view using a weapon readily adaptable to a wide range of opponents. But these terms of defence and attack bespeak a kind of adversarial attitude to scientific discussion which is inappropriate. What we learn from Ernst von Glasersfeld is that human agents work together with viable constructs from their experience until discrepancies appear (Glasersfeld, 1982), until the external source of experience produces constraints that reveal that the motor sequences so far deemed to be advantageous suddenly prove disadvantageous. It is therefore much more a matter of discovery and inquiry that must be set in motion when there are such ‘problematic happenings’ as Stephen Toulmin (1971, p. 29) calls them, and the solution is more likely to take a dialectical form than that advance that is made through revealing some logical inconsistency in the opponent’s case. The very construct of constructivism itself can surely be shown to be viable even though a number of opponents have come to believe that it is vitiated by a hidden idealism and, worse, a theoretically embedded relativism. This is how they read his agreement with Vico that facts are made and not given (Glasersfeld, 1984, p. 27), that between the constructs we have and the external there is no kind of correspondence (ibid., 1982, p. 615), that the regularities upon which our agreements in truth are based can only be assumed and not finally believed (ibid., 1989, p. 438), that ontological reality cannot be straightforwardly assigned to everyday objects-and, worse, in their view, to selves (ibid., 1989, p. 445). An anti-Piagetian such as D.W.Hamlyn (1971) insists that ‘Experience itself always involves confrontation with particulars’ (p. 21). There is something deeply disturbing to the realist mind in the contemplation of the notion that objectivity might not have the reassuring actuality that one would like it to have, and it arouses deep suspicions of an ingrained relativism, particularly among philosophers, to read someone who boldly sets out to analyse such a fundamental concept, declaring that objects had better be looked upon as ‘instrumental hypotheses and tentative models’ (Glasersfeld, 1989, p. 447). Furthermore, his belief that it is out of experience that the constructs are made lays his theory open, it is argued, to accusations of subjective idealism and hence of solipsism.
