Abstract

Radical constructivism (RC), introduced by Ernst von Glasersfeld, is an instrumentalist theory of knowledge that challenges the notion of knowledge as a picture or representation of a real, external world. Instead, RC, by integrating ideas from different theoretical fields - such as cybernetics, evolutionary biology, and evolutionary psychology - considers the purpose of the cognitive organism to construct knowledge not to achieve truth, but to construct perceptual and conceptual structures that help to maintain adaptation and cognitive equilibrium. However, the basic question here is, by what character these structures can achieve the purpose. By examining Glasersfeld's writings, this paper argues that the character is a "functional fit", which is based on a fundamental shift in RC, i.e. the shift from "matching" to "fitness". From this point of view, the "fit knowledge" is not due to its match with the external reality, but due to its repeated success in solving a specific problem, it is viable, and by preventing unwanted changes or perturbations, it gives order to the experiential world of the organism and helps to maintain its cognitive equilibrium. This perspective has the potential to create transformation in various fields, from education to ethics and social issues. Therefore, this paper, while examining the basic concepts of radical constructivist epistemology, also deals with its theoretical and practical applications.