There seem to be as many definitions of constructivism as there are minds to construct them. At least this is how it felt after reading the chapters by Duit (chap. 14), Saxe (chap. 15), and Spivey (chap. 16). Or perhaps there are as many questionings of constructivist ideas as practices in the field of education. For example, a teacher experiences a different set of constraints than a researcher or a designer, and these constraints in turn shape theories of learning in different ways.

There are many issues presented, touched on, and presupposed in the chapters in this volume-issues that have, in some cases, ancient historical roots and many variants and complexities. In searching for a framework within which I felt I could approach these chapters in some integrated way, I was forced back to these historical roots. This volume is a moment in a very long conversation (Melchert, 1991), and it cannot be understood outside of the context of that conversation. Consequently, I elaborate on the general historical issues, commenting on and criticizing them as well as their instances herein.

The basic question that is raised by the chapters by Wertsch and Toma (chap. 10) and Bauersfeld (chap. 9) is, “How compatible are the theories of radical constructivism, sociocultural approaches, and social constructivism?” The authors imply that the three theoretical positions can be made compatible, but, to my knowledge, an explicit discussion of whether and how this might be accomplished has yet to be offered. In this chapter, I question whether, as indicated by Wertsch (1985b), the Vygotskian program can be simply modified to accommodate a Piagetian perspective. Then, drawing on the classroom examples provided by Bauersfeld, and Wertsch and Toma, I suggest that an integrated theory is desirable, but difficult to achieve. I discuss some points of contact and conflict between the theories, and then offer a set of assumptions for an integrating theory.

Contemporary constructivism is not a totally new idea. On the contrary, there is a long-standing tradition of constructivist ideas in philosophy, in the philosophy and practice of education, and also in empirical research on students” preinstructional conceptions in science. Steffe (1990b) briefly outlined some aspects of the history of constructivism. For instance, he pointed out that Kant (1724–1804) held major constructivist ideas. Jung (1985) interpreted Bacon’s (1561–1626) ideas in Novum Organum within such a framework.

Is constructivism one or many schools of thought? This is not as trivial a question as it sounds. If one, then perhaps almost everybody belongs, which does not tell us much. It leads to such outcomes as neobehaviorists claiming that we are all constructivists now. Neobehaviorists should not be dismissed too lightly because the models of cognition in the work of Ausubel, Gagné, and others are subtle and complex. Ausubel (1968) said long ago that “the most important single factor influencing learning is what the learner already knows. Ascertain this, and teach him accordingly” (p. i). Coupled with his work on meaningful versus discovery learning, this seems to place him close to some weak form of constructivism. But Lewin (chap. 23) has demonstrated that a lack of clarity in representing constructivism may allow its appropriation by the most authoritarian of pedagogies. One of the central tasks of this chapter is to clarify what is and what is not constructivism.

Practices of education must necessarily proceed on the basis of assumptive networks, that is, preliminary beliefs about the nature of human beings, their capacities, and their relationship with the world and each other. In the case of education, the pivotal concept is that of knowledge. How do we define or conceptualize knowledge, such that educational processes are demanded or desirable, or that certain educational practices are to be favored over others? It is clear that disparate concepts of knowledge lend themselves to differing views of the educational process. If we believed, along with certain romanticists, that “the heart has its reason,” we might replace books and lectures with intense encounters of both interpersonal and spiritual variety. Should we believe, along with the Ilongot of Northern Luzon, that knowledge is to be gained in the throes of anger or in the hunting of heads, then formal training in schools might be replaced by battle experience. Beliefs about knowledge, then, inform, justify, and sustain our practices of education.

Excerpt: The development of a constructivist theory of knowing has been the focus of my interest for several decades. It was a philosophical interest that arose originally out of work concerning first the structure and semantics of several languages and later cognitive psychology. The title of this chapter, therefore, may need an explanation. Rosalind Driver, Reinders Duit, Heinrich Bauersfeld, and Paul Cobb, can speak about teaching from their own immediate experience, whereas I have never taught any of the subjects that you are experts in. So when I focus on the theory of constructivism, you may wonder why on earth a proponent of such a very peculiar theory of knowing should have anything to say about education in mathematics or science. It is a question I have often asked myself. If all goes well, you will see some justification at the end of my essay.

Key words: radical constructivism, education