Philosopher & Cybernetician he spent large parts of his life in Ireland [1940s], in Italy [1950s] and the USA [current]. Elaborating upon Vico, Piaget’s genetic epistemology, Bishop Berkeley’s theory of perception, James Joyce’s Finnegans Wake and other important texts, Ernst developed his model of Radical Constructivism - which is an ethos shared by all of these writers to one degree or another, sometimes it is difficult to see where their epistemological agreements begin and end - but that is part of the fun.
http://es.wikipedia.org/wiki/Ernst_von_Glasersfeld
http://www.infoamerica.org/teoria/glasersfeld1.htm
http://www.oikos.org/vonen.htm