Is a unified theory of psychology really impossible? In a previous post, I took the perspective of a skeptic and explained why a unified theory of psychology is essentially impossible, both in terms of developing mathematical equations for human behavior grounded in physics and in terms of developing a workable, conceptual system that frames the subject matter in a coherent way. Here I want to begin to offer a reply to those arguments.
The discipline to look toward to ground our question of whether or not a unified theory of psychology is possible is not physics, but biology. Thus, let us ask the question: Is there a unified theory of biology? The answer to this question is "no" and "yes", depending on what is meant by a unified theory.
Paralleling the division highlighted in the previous post, the answer is "no" in the sense that there is no Unified Theory of Biology grounded in precise mathematical equations that effectively describe all biological behavior. Although some have attempted to accomplish such a theory via energy and thermodynamics, many biologists doubt whether such a mathematical formulation is even theoretically possible.
But if, by unified theory, we mean conceptual unification, then the answer is yes. Biology was unified by the modern evolutionary synthesis. The modern synthesis refers to the theoretical merger of Darwin's theory of natural selection and genetics. Natural selection operating on genetic combinations across the generations has allowed for the conceptual unification of biology.**
In the 1920s, biology was a fragmented science. Fundamentally incompatible versions of evolution were being advanced (natural selection was a minority view), and there was a vitriolic split between the "naturalists" and "experimental geneticists." The text, The Evolutionary Synthesis: Perspectives on the Unification of Biology provides a wonderfully rich and detailed history of how disputes in biology fractionated the discipline and how they were ultimately resolved with the formation of a single, coherent paradigm. Consider the following excerpt:
The crucial significance of the synthesis, then, was the fusion of the widely diverging conceptual frameworks of experimentalists and naturalists into a single one. There is every justification to designate this process a synthesis.When I (Mayr) read what was written by both sides during the 1920s, I am appalled at the misunderstandings, the hostility, and the intolerance of the opponents. Both sides display a feeling of superiority over their opponents "who simply do not understand what the facts and the issues are." How could they have ever come together? Just as in the case of warring nations, intermediaries were needed, evolutionists who were able to remove misunderstandings and to build bridges between hierarchical levels. These bridge builders were the real architects of the synthesis
Mayr's articulation of the state of affairs in biology in the 1920s reads with great applicability to the current state of psychology and my book, A New Unified Theory of Psychology, lays out a pathway toward conceptual synthesis. It outlines a new metapsychology that can assimilate and integrate key ideas from disparate views in a coherent way. It is a work in bridge building.
But, the critic appropriately asks, isn't this what Arthur Staats tried to do? Why do I think my conceptual system will succeed where Staats' failed? That will be the subject of the next post.
**For those of you who believe that evolution is "just a theory", I am sorry, but you have been grossly mislead by your education. Doubt about evolution is a function of American sociology (i.e., sociopolitcal/religious/contextual forces), not real biological science. Also, please note that 'theory' in advanced sciences doesn't mean debatable speculation. It means a causal explanation for empirical observations. Consider for example, that biologists talk of "cell theory" or that physicists talk of Einstein's theory of general relativity. The theory that grounds the modern evolutionary synthesis is simply one of the best supported ideas in science. Although it certainly might need to be amended as more knowledge is obtained, is nevertheless is clearly a foundational truth and to "not believe" in it is like "not believing" in the Periodic Table.