Von Glasersfeld coined the term radical constructivism and spent large parts of his life in Ireland (1940s), in Italy (1950s) where he worked with Silvio Ceccato, and in the US. Elaborating upon Giambattista Vico, Jean Piaget's genetic epistemology, Bishop Berkeley's theory of perception, James Joyce's Finnegans Wake, and other important texts, von Glasersfeld developed his model of Radical Constructivism, which is an ethos shared by all of these writers to one degree or another.As von Glasersfeld says “knowledge is the result of an individual subject’s constructive activity, not a commodity that somehow resides outside the knower and can be conveyed or instilled by diligent perception or linguistic communication.” The radical constructivist movement abandons the traditional philosophical position of realism according to which knowledge has to be a representation of an essential reality. Constructivism adopts the relativist position that knowledge is something which is personally constructed by individuals in an active way, as they try to give meaning to socially accepted and shared notions.
Glasersfeld, E. von, (2001) The radical constructivist view of science. In: A. Riegler (Ed.),Foundations of Science, special issue on "The Impact of Radical Constructivism on Science", vol.6, no. 1–3: 31–43.
Glasersfeld, E. von (1989). “Cognition, Construction of Knowledge and Teaching.” Synthese, 80(1),121-140.
Glasersfeld, E. von (1990). “Environment and Education.” In L.P. Steffe & T. Wood (eds.),Transforming Children’s Mathematics Education: International Perspectives, (pp. 200-215). Hillsdale, NJ: Lawrence Erlbaum.
Glasersfeld, E. von (1992). “Questions and Answers About Radical Constructivism.” In M.K. Pearsall(ed.), Scope, Sequence, and Coordination of Secondary Schools Science, Vol. 11, Relevant Research, (pp. 169-182). Washington DC: NSTA.
^(Glasersfeld, E. von (1990). “Environment and Education.” In L.P. Steffe & T. Wood (eds.), Transforming Children’s Mathematics Education: International Perspectives, (pp. 200-215). Hillsdale, NJ: Lawrence Erlbaum.p. 37).