This blog post examines how much evolutionary psychology can explain human behavior, critically exploring the tension between innate and environmental factors. Through this, it considers both the explanatory limitations and potential of evolutionary psychology.
Recently in Korea, social controversy has arisen over claims that high school textbooks should delete or reduce content related to evolutionary theory. At the core of this debate lies the fundamental question of whether evolutionary theory is a scientifically established fact or remains merely a hypothesis. Evolutionary theory inherently faces limitations because it must explain events from the distant past, long before humans existed, making it difficult to prove through experiments or direct observation. For this reason, evolutionary theory has long been a subject of academic and social debate.
In this context, the author of “The Old Toolbox” expands upon existing evolutionary theory, presenting a new academic perspective called evolutionary psychology. The theory of evolution posits that organisms adapt to their environment, gradually changing from simple to complex forms. Traits advantageous in the struggle for survival are passed down, while those that are not are eliminated. Evolutionary psychology goes further, explaining that the human mind itself is a collection of numerous psychological mechanisms designed by natural selection to effectively solve various adaptive problems repeatedly encountered throughout our long evolutionary history. In other words, the author of this book argues that humans are not born as blank slates whose behavior is solely determined by education and environment later in life. Instead, the human mind itself is designed by natural selection to perform specific purposes, thereby guiding behavior.
I wish to take an opposing stance to the author’s claims on two fronts.
The first reason for my opposition is that, contrary to the author’s claim that human behavior is already innately designed and manifested, I believe human behavior is actually far more strongly influenced by acquired factors such as educational processes, environment, and culture than by innate factors. Let me illustrate this with an example. Suppose a cafe has ample seating. Many people tend to prefer seats by the window or against the wall—that is, seats at the edge—rather than seats in the center. The author traces the cause of this phenomenon back to the time when our ancestors lived as hunter-gatherers on the African savanna. Back then, locations on the edge or with open views, where prey or predators could be spotted at a glance, offered a survival advantage. Thus, the psychological mechanisms adapted to this environment have been passed down to the present day, making us instinctively prefer spots with good visibility or edge seats.
However, I believe interpreting seat selection in cafes solely through this evolutionary psychological lens is an overreach. Seat choice can vary significantly based on individual preferences or habits, and one’s psychological state in a given situation also plays a major role. Some people might prefer a window seat at the edge over a center seat because it feels less stifling, while others might actually feel more comfortable in a center seat where they feel less scrutinized by others. Thus, seat selection can vary based on factors like personal experience, disposition, or mood on a given day, and it doesn’t necessarily need to be explained solely by evolutionary mechanisms. Furthermore, such an evolutionary psychological explanation risks appearing like a forced interpretation, fitting any situation regardless of context. If we assume people prefer the center seat, an evolutionary psychology explanation might suggest that humans have evolved to favor the center—the area offering the most protection from external threats—because our species has pursued safety throughout generations. However, the ability to retroactively explain any outcome through evolutionary logic can weaken the persuasiveness of such interpretations.
Next, let’s examine another case. Many people deeply immerse themselves in dramas or movies and show strong emotional responses, even though they clearly recognize these are fictional stories. The author explains this by suggesting that during the process of designing the human mind through natural selection, strong interest and pleasure were built into the activity of gathering social information about others. Considering that the ability to grasp social information played a crucial role in human survival and cooperation, this explanation might seem partially valid. However, this explanation alone struggles to fully account for the phenomenon where many people enthusiastically engage with purely fictional stories unrelated to social information, or with simple gags and humor devoid of any lesson or information. I believe there are limits to explaining why people find enjoyment and interest in stories or scenes that seem to have no practical meaning solely as products of evolutionary adaptation. I find it more convincing to explain why we listen to and immerse ourselves in fictional stories through the lens of human social traits—the desire to share meaning and exchange emotions within a social context—rather than through an evolutionary psychological explanation.
Second, I wish to point out that the core premise of evolutionary psychology asserted by the author—that ‘various psychological mechanisms were formed through natural selection’—is itself unclear. Biological evolution can be explained as follows: traits possessed by the parent generation that are advantageous for survival and reproduction are passed on to the next generation, while disadvantageous traits gradually disappear. This is a process relatively clear from the perspective of genes. However, questions remain about whether the ‘psychological mechanisms’ presupposed by evolutionary psychology can be explained in the same way from this genetic perspective. If psychological mechanisms can also be considered part of genes, wouldn’t they ultimately be reducible to the problem of biological evolution? If so, the question arises as to why it must be named as a separate discipline called evolutionary psychology.
In this book, the author cites humans’ ability to recognize each other’s faces as an example, explaining that this ability is a special ‘instinct’ we all possess today because it conferred survival and reproductive advantages in our distant evolutionary past. Here, the author views ‘instinct’ as the result of psychological adaptations passed down to offspring. However, at this point, I believe it is more valid to understand ‘instinct’ as a functional characteristic of the brain rather than a psychological phenomenon. Indeed, the author also mentions that damaging specific areas of the brain results in the loss of the ability to distinguish human faces. This implies that certain brain regions are responsible for the function of facial recognition, and such a function can certainly be genetically transmitted to offspring. Therefore, while we can acknowledge that the ability to distinguish human faces is a product of evolution, it is a stretch to interpret this directly as meaning that a psychological mechanism has been inherited. Furthermore, this ability is not a trait unique to humans. Fish use ultraviolet wavelengths to distinguish each other, and bats identify individuals through echolocation. Thus, the ability to recognize and differentiate among others manifests in diverse ways across animals. This can be explained by the functional workings of the brain and nervous system, and it does not necessarily need to be interpreted as a psychological process.
The author argues in this book that various phenomena across human life can be explained through evolutionary psychology. However, many of these explanations feel closer to theoretical hypotheses based on inference than to empirically verified findings. In other words, even though human behavior in modern society can be sufficiently interpreted from other perspectives, the explanations often remain at the level of presenting one possible interpretation within an evolutionary psychological framework. I find explanations suggesting that human behavior is shaped by inherited personality traits from parents, along with acquired factors like educational processes and social environments, more persuasive than these evolutionary psychological interpretations. Furthermore, I believe the very classification of evolutionary psychology as a distinct discipline is ambiguous. It can appear as a discipline that is part of evolutionary theory while simultaneously encompassing the realms of both psychology and genetics. This results in an overlapping field that could be explained by evolutionary theory, psychology, or genetics. For these reasons, I cannot help but remain skeptical of the evolutionary psychological explanations presented in The Old Toolbox overall, and this sense of unease does not easily dissipate even after reading the book.
