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Radical Constructivism

What is Radical Constructivism
and Who Are Its Proponents?

The notion "radical constructivism" (RC) was coined by Ernst von Glasersfeld in 1974 in order to emphasize that from an epistemological perspective any constructivism has to be complete (or "radical") in order not to relapse into some kind of fancy realism. The basic tenet of RC is that any kind of knowledge is constructed rather than perceived through senses. As such, RC does not present a metaphysics in the strict sense as it does not make statements about an outside reality ("No statement" means neither confirming nor denying reality. The subject of much criticism, RC equals solipsism, doesn't therefore apply). Now, the idea itself does not originate in EvG. Forerunners of the RC movement in the 18th century were Giambatista Vico, whose dictum "verum ipsum factum" already pointed in the direction of knowledge construction, and George Berkeley whose claim "esse est percipi" challenged metaphysics.

On a slightly different path, the cybernetic one, Heinz von Foerster approached the topic of what was called second order cybernetics. It focuses on self-referential systems and the importance of eigenbehaviors for the explanation of complex phenomena. Eventually, this idea would emerge the concept of "operational closure": any cognitive system is semantically independent (and impenetrable). From the late 50s to the mid 70s, HvF had been running the Biological Computer Laboratory (BCL) at the University of Illinois at Urbana-Champaign which was a dwell of people thinking in similar lines. Among others, prominent members of the BCL were

  • Humberto Maturana who, as the founder of the theory of autopoiesis, focuses on the central role of the observer;
  • Francisco Varela who developed the ideas of circularity and 'enacted' cognition further;
  • W. Ross Ashby who was a main figure in the cybernetics movement;
  • Gordon Pask who developed a conversation theory.

In Germany, an avalanche was triggered in the late 80s by translations of major works by the above authors, plus original contributions in German, such as Siegfried J. Schmidt, Hans-Rudi Fischer, Gerhard Roth, Gebhard Rusch, and others. Also of German origin, but independent from the others, was Jakob von Uexküll, whose work in the 1920s and 1930s focused on the internal cognitive world of organisms.


Autopoiesis: A process whereby a system constitutes and maintains its own organization

Cybernetics: The science of communication and control in animal and machine

Eigenbehavior: The behavior through which a system asserts its autonomy from other systems

Epistemology: The theory of knowledge

Metaphysics: The theory of reality

Realism: The idea that reality exists independently from the observer

Second order Cybernetics: The cybernetics of observing systems

Solipsism: The claim that reality does not exist

Created: June 2000. Last update: 26 Mar 2004

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Alex Riegler 2000. All rights reserved. Part of the Radical Constructivist Homepage.
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