Concurs with N. M. Agnew and J. L. Brown’s views that ontological and epistemological presuppositions impose certain constraints on the pursuit of knowledge. These authors have captured the constructivist thrust of G. A. Kelly’s (1955) psychology of personal constructs in their central theme.

Responds to comments by D. T. Campbell; D. N. Robinson; M. J. Mahoney; K. M. Ford; and J. Adams-Webber on the present authors’ articles. Issues related to the concepts of pragmatic and existential constructivism, relativism, realism, and entrainment are addressed.

Traditional views of knowledge are being challenged. An emerging “constructivist” perspective, as proposed by George Kelly, an engineer turned clinician, suggests that to a large degree we construct reality. In his “constructive alternativism” Kelly assumes that we validate our hypotheses and beliefs through subjectively construed goodness-of-fit criteria applied to perceived differences between anticipations and feedback. His model of construing is compatible with those emerging in the history and philosophy of science and in cognitive psychology. Nevertheless, constructivists must answer a perplexing question: How can fallible knowledge, constructed as it is from abstracted and incomplete representations of objects and events, capture and maintain our confidence, as it does, and furthermore prove highly functional, as it does?

An evolving theory known as “constructivism” challenges the traditional view of how we generate and revise knowledge. Constructivism helps address a major issue raised by modern scholars of the history and philosophy of science, and decision theory. The question is: How do we reduce the search and solution space of complex and changing environments to “mind size” (i.e., to fit our limited memory and computational capacity)? One emerging answer is that we rely heavily upon robust presuppositions and simplified representations of environmental structure. However, such constructed knowledge is likely to be highly fallible, relying as it must on impoverished data bases in the service of strong expectations or paradigms. In this paper we address two issues: Under what conditions can knowledge be highly fallible and at the same time be highly functional?; Can we make a plausible case, within this constructivist frame of reference, for realism, for knowledge that approximates “reality”?

Personal construct and family systems theories can profit from an exchange of ideas concerning the relationship between their personal and interpersonal aspects of construction. This article examines three possible points of contact between the two orientations. First, we suggest that personal construct psychology could profit from addressing the important contributions of the family context to the development of each individual’s system. Second, we address the impact of the person’s constructions on the larger family system. Third, we suggest that the family system itself develops a system of shared constructions that define and bind its identity and interactions. Each of these areas of interface carries implications for therapy, and specific intervention techniques corresponding to each of these are discussed.

The Tree of Knowledge, by Humberto Maturana and Francisco Varela, is a landmark attempt to integrate biology, cognition, and epistemology into a single science, reversing the dualism of fact and value, and of observer and observed, that has haunted the West since the seventeenth century. The authors see perception as a reciprocal and interacting phenomenon, a “dance of congruity” that takes place between a living entity and its environment. This, they argue, implies a relativity of worldviews (there are no certainties), as well as the existence of a biology of cooperation going back millions of years. Recognition of a lack of absolutes, and of the nature of perception itself, they assert, make it possible for us today to change things for the better, as a deliberate and conscious act. What is overlooked in this discussion, however, are the origins and nature of conflict. By being pointedly apolitical, the authors wind up implying that one worldview is as good as the next. Cognitively speaking, the substitution of Buddhism for politics is a serious error, leaving, as it does, too many crucial questions unanswered. It is thus doubtful whether the biological argument being advanced here can stand up to serious scrutiny, and whether the dualism of modern science has indeed been overcome. Yet The Tree of Knowledge remains an important milestone in our current efforts to recognize that science is not value-free, and that fact and value are inevitably tied together. We are finally going to have to create a science that does not split the two apart, and that puts the human being back into the world as an involved participant, not as an alienated observer.

This article is a critical analysis of Maturana’s recent works as applied to the social and behavioral sciences. It proposes that there is a major contradiction in Maturana’s “structure determinism” which prevents a consistent epistemological and ontological perspective. The concept of change is viewed as crucial to understanding Maturana’s work and to extending his ideas to form a consistent philosophical viewpoint, which is defined as the third epistemology for the social and behavioral sciences. Accordingly, the idea of structure is abdicated. It is proposed that the new perspective on Maturana’s work has practical application to the social and behavioral sciences, in general, and family therapy, in particular.