Unifying Psychology: Shared Ontology and the Continuum of Practical Assumptions

Critics have described psychology as a science impaired by disunity. The most recent special issue of Review of General Psychology sought to specifically address this concern, seeking perspectives from a wide range of theorists, each of whom offered their tradition's approach to how psychology as a whole may be integrated into a more unified whole. To continue this discussion, this article draws upon examples from the special issue, the disunity crisis literature, and wider writings in the philosophy of science, to explore the theoretical and conceptual divisions that foster ambiguity, confusion, and apparent irreconcilable differences between the disparate fields of psychology. The authors conclude that the majority of contemporary, scientific psychology is oriented toward a shared physical ontology, which can serve as a common grounding point from which the conceptual and theoretical differences of disparate fields may be meaningfully framed and evaluated. To this end, this article proposes that the various research traditions of psychology can be understood through their positions along a continuum of practical assumptions, which embodies the inherent conflict between two scientific priorities: metaphysical certainty (the safe end of the continuum) and practical experimental predictions (the risky end of the continuum). Three theoretical perspectives offered in the unification special issue are examined under this framework: situational realism (a distinctly safe approach), developmental evolutionary psychology (an intermediate approach), and the Tree of Knowledge unified theory (a relatively risky approach). The authors explore how the recommendations of each approach can be seen as a function of its position on the continuum of practical assumptions, and the implications of this understanding for future integrative efforts is discussed.

Evolving from Methodological to Conceptual Unification

The absence of a philosophical system that can effectively address the profound problems that exist at the heart of psychology has resulted in the discipline becoming increasingly defined and unified simply by its commitment to the scientific method. This article articulates why unification via method is a weak intellectual solution and explains how the Unified Theory ( Henriques, 2011 ) provides the needed framework so that the field can evolve from its current unity via method to a more mature conceptual unity that clearly defines psychology, grounds it in a scientific worldview, and assimilates and integrates its key insights into a coherent whole.

Special Section: The Critical Role of the Dialectic in Viable Metatheory

Henriques (2008) persuasively argues that his Tree of Knowledge (ToK) System provides a more viable alternative to Wilson's (1998) consilience model as a framework for integrating knowledge generated by the natural sciences, social sciences, and humanities. I selectively deconstruct the ToK System to demonstrate that its capacity to solve problems through integrative solutions and to advance interdisciplinary conjunctions derives from its pervasive dialectical ontology and epistemology. Emphasis is on analyzing Behavioral Investment Theory, the Justification Hypothesis (the JH), and Henriques' solution to the problem of psychology—all essential to unifying the three great branches of learning. I also suggest directions for further development of the JH, rooted in the psychoanalytic classical—relational dialectic. Potent implications of Henriques' formulations for epistemological bridging within psychology and for multidisciplinary integration are discussed.

Special Section: The Problem of Psychology and the Integration of Human Knowledge

The central thesis of this essay is that the problem of psychology lies at the very heart of the difficulties associated with integrating human knowledge. The startling consequence of this insight is that it means the solution to psychology's epistemological woes opens up a new pathway for achieving unified knowledge. A brief overview of the fragmentation of knowledge will be offered and special attention will be paid to Wilson's (1998) proposal. The problem of psychology, Wilson's failure to address it, and the reasons why it is integral to any proposal for unifying knowledge will then be specified. The article concludes with an articulation of how the Tree of Knowledge (ToK) System solves the problem of psychology, resolves many of the fundamental issues associated with integrating human knowledge, and is commensurate with the foremost concerns of natural scientists, social scientists, and humanists, allowing for objectivity, coherence, and pluralism.

Special Section: Pruning the Tree of Knowledge

There are several intellectual projects embedded within the Tree of Knowledge (ToK) System and they tend to blur together at critical junctions. The aim of this commentary is to identify some of these strands of analysis and their implicit metaphysical presuppositions. It is argued that the presuppositions are not consistent across the different strands. The strands can continue to be pursued independently, insofar as they have distinct purposes. However, the incompatible presuppositions are surfacing in the effort to combine the strands into a single system of analysis.