Purpose: To develop a realistic view that integrates the idea that knowledge is a constructive process. Problem: In the controversy between realism and constructivism, both sides have often misunderstood each other. Many realists still consider constructivism as a kind of idealism. And constructivists often assume that realists believe they have direct access to things as they really are. It seems necessary to clarify the statements of either side, to rule out some misunderstandings, and then to discuss anew the central epistemological problems. Solution: A version of realism is proposed that takes into account constructivist ideas and objections. Realism as presented here is not opposed to the idea that cognition is a constructive process. According to this view, reality is something we presuppose in any attempt to attain knowledge though we can never be certain how things really are. Having knowledge amounts to the preliminary judgment that some hypotheses seem to correspond to reality better than others. In addition, it is demonstrated that a constructivist position that reduces the claim to knowledge even further does not solve the problems better but creates new ones. Finally, Mitterer’s non-dualizing view of descriptions is discussed. It is argued that description necessarily presupposes something different from language.
According to constructivism, the world we can know is a construction and it is not possible to gain knowledge about the world as it is in itself. This thesis of constructivism has been criticized as being self-refuting. It is discussed whether this criticism is sound. Constructivists have tried three ways in order to avoid self-refutation. It is argued that the first two ways are unconvincing. The third solution is tenable. However, at a closer look the third solution turns out as a moderate kind of realism since it gives up the central claim of constructivism.
Context: A number of objections that are frequently raised in the literature against radical constructivism, including: the charge of solipsism, allegations of self-refutation, social and moral reservations, and the accusation that RC cannot explain the success of science. Problem: These four objections are sought to be refuted. Results: 1. Solipsism is only troublesome against the background of a realist ontological perspective. 2. The truth-value of any proposition is only defined relative to some ontological context, thus self-refutation, as constituting a logical problem, does not arise. 3. Any ethical argumentation derives from one’s own personal views on ethical matters: their construction being a personal responsibility such that no one else can tell a person how to construct the “right ethics.” 4. In the relativist ontology of radical constructivism, a scientific theory is regarded as a model imposed on natural phenomena; its success is due to the capabilities of its constructor/scientists. Implications: It is found that the objections are based on an (overt or tacit) adoption of the antithetical viewpoint of scientific realism. In other words, radical constructivism is being criticised for not promoting a realist ontology.