Abstract
Context: Few professional philosophers have addressed in any detail radical constructivism, but have focused instead on the related assumptions and limitations of postmodern epistemology, various anti-realisms, and subjective relativism. Problem: In an attempt to supply a philosophical answer to the guest editors’ question, “Why isn’t everyone a radical constructivist?” I address the realist (hence non-radical) implications of the theory’s invocation of “others” as an invariable, observer-independent, “external” constraint. Results: I argue that constructivists cannot consistently defend a radically subjectivist theory of knowing while remaining entirely agnostic about the nature and existence of the larger world (including independent others). That is, any non-solipsistic account of human experience must explicitly acknowledge its extra-subjective, ontological dimension. Implications: It follows that no pedagogical, social, philosophical, or commonsensical insight associated with so-called “trivial” or “social” constructivism survives or receives any support from the move to radical constructivism