Psychotherapy, and the science supporting it, is primarily a province in the realm of psychology, a professional discipline with many components. An unfortunate consequence of psychology’s many subfields is the common tendency for many to give only cursory attention to advancements in their sister disciplines. One such advancement has been the integration of psychological, evolutionary principles and behavioral genetics. This new fusion is enabling a deeper understanding of the origins of emotion, cognition, and human behavior, and the problems that arise when these processes lead to suffering or dysfunction. Applying evolution and genetics to help people with psychological problems is evidence based and beneficial. Human beings, like all life on this planet, are the product of evolution by means of natural selection that occurred through stochastic genetic changes.
It follows that understanding natural selection is a fundamental requirement for understanding the brain and its mind, both of which were shaped by natural selection. Very few will dispute that multifaceted organs such as the eye, the heart, and the brain are the result of millennia of descent with modification. Of course, most mutations are deleterious, but given vast intervals, there were numerous mutations that produced incremental advantages. And if one of these advantages provided even a very small reproductive benefit, it would be passed along to posterity. And over vast periods of time, these mutations combined and interacted with other genetic changes to produce new organs, new brain functions, or entirely new species. In an extremely distilled form, this is the essence of Darwin’s model of species change, or what is commonly referred to as evolution—incidentally, a term that Darwin himself did not use. In the first edition of the Origin of Species by Means of Natural Selection or the Preservation of Favored Races in the Struggle for Life, Darwin did not use the word evolution even once. In the final chapter, he wrote, “There is grandeur in this view of life, with its several powers, having been originally breathed into a few forms or into one; and that, whilst this planet has gone cycling on according to the fixed law of gravity, from so simple a beginning endless forms most beautiful and most wonderful have been, and are being, evolved.
Over the last few decades, evolutionary principles have been shown to be provident and convincing explanations for many psychological phenomena. Like all paradigm changes in science, it has elicited contention and debate, some examples of which will be discussed in this book. However, the growing body of evidence has left little doubt that this approach has offered powerful new ways to understand human thinking and behavior. Unlike many earlier schools of thought in psychology, the work in evolutionary psychology has almost exclusively been limited to explanations as opposed to applications. Such accounts have provided new insights into a wide range of concerns relevant to psychological clinical practice such as jealousy, aggression, sexual orientation, love, and even psychosis.
This book will demonstrate that evolution is at least as important to clinical psychology as it is to the developmental, biological, and neurological branches of the science. The study of natural selection has revealed that evolutionarily adapted traits are best understood when viewed as products of the environment in which man resided when those traits evolved. Evolutionary psychologists refer to this ancestral setting as the environment of evolutionary adaptedness (EEA). Importantly, this does not refer to a specific time or place but rather to any setting that was sufficiently different from the present so as cognitive or behavioral traits that arose during that time are no longer optimal. That is, many of our psychological inclinations evolved to aid survival in settings very different from the one in which we now reside. This will be shown to be an essential premise of informed cognitive therapy (ICT), which adds several essential features to CBT. Most importantly, the clinicians working from this perspective must be able to apply the principles of behavioral genetics and evolutionary psychology. Evolution and behavioral genetics provides mental health clinicians the information necessary to parse the historical problem of nature versus nurture. Clinicians, as well as theoreticians, need to be aware that people now live in settings radically different from the ones in which their distant progenitors developed. Consequently, many of our methods of dealing with problems, perceiving our environment, judging others, or even assessing ourselves don’t match the current demands of our world. This divergence has led to, many psychological problems that superficially appear to be disorders that may actually be functional solutions mismatched with a new environment (Gluckman & Hanson, 2006). This premise will require that mental health professionals become conversant not only in the requirements of daily living but the demands of living eons ago. They will need to understand the role the environment in which our ancestors evolved has on today’s thinking and behaving.
More than 30 years ago I was collaborating with Albert Ellis, the founder of cognitive behavioral therapy (a term he coined in 1969, despite preferring to call his approach rational emotive behavioral therapy). While working on the book Rational Eating, we began to discuss innate traits versus those constructed by individuals themselves. Ellis made it clear that he was convinced that people were innately inclined to be the way they were. He was confident that through forceful and persistent effort, people could overcome their innate inclinations, such as irrationality, demandingness, ans self- centeredness.