Since the mid 1970s, Ernst von Glasersfeld has had an impact on mathematics and science education through his fundamental insights into the nature of knowledge and knowing. This volume of papers honours his work by building on his model of knowing. The contributions by researchers present constructivism in action, tying the authors' actions regarding practical problems of mathematics and science education, philosophy and sociology to their philosophical constraints, giving meaning to constructivism operationally. The book begins with a retrospective analogy between radical constructivism's emergence and changes in what is thought of as "certain" scientific knowledge. The five remaining sections address broad epistemological issues; the inclusion of ethics with radical constructivism and the questions of what "social interaction" and "self" mean within a constructivist framework; research on instructional design; conceptualizing and designing programmes from a constructivist perspective; and reflections on constructivism in a political arena and on future directions constructivism might take. Through the book the epistemological perspective of constructivism is debated, contested and clarified, and then applied in a variety of practices and inquiries. It aims to increase understanding of constructivism and Glasersfeld's achievement, and is vibrant evidence of the continued vitality of research in the constructivism tradition.
