Is Human Psychology Better Explained by Evolution or Design?
Editor’s note: This article is adapted from a chapter in the recent book from South African publisher AOSIS, Science and Faith in Dialogue, which is free to download. Find more information about the book here.
“We are survival machines,” wrote atheist biologist Richard Dawkins, “robot vehicles blindly programmed to preserve the selfish molecules known as genes.”
Dawkins meant that the purpose of human beings is nothing more than to survive and reproduce. We evolved, and we did so in order to pass on our genes — nothing more and nothing less. It is difficult to imagine a more materialistic message. However, rather than our being mere “survival machines,” humans in fact have many special behaviors that far exceed the requirements for survival and reproduction.
Introducing Evo Psych
Evolutionary psychology (also called “evo psych”) is a field that aims to explain human behavior, mental capacity, and intellectual abilities strictly as the result of unguided natural selection preserving beneficial traits. Under this view, it is not just our bodies that evolved, but also our brains and behaviors, including our moral and religious impulses. That is, evo psych desires to explain, in strictly naturalistic terms, all of human nature. The project traces its roots to Darwin himself, who wrote in The Descent of Man that he sought “to shew that there is no fundamental difference between man and the higher mammals in their mental faculties.” A modern interpretation is articulated by philosopher Daniel Dennett:
Everything we value — from sugar and sex and money to music and love and religion — we value for […] evolutionary reasons, free-floating rationales that have been endorsed by natural selection.
The field of evolutionary psychology has long faced accusations of purveying “just-so stories.” In an article titled “How the Human Got Its Spots,” psychologist Henry Schlinger writes that “evolutionary psychology, while different in many respects from its predecessor sociobiology, is still subject to the accusation of telling just-so stories.” Proponents of evolutionary psychology reply that they are merely making inferences to the best explanation. But are all possible explanations even considered within this field? Evo psych defenders David Barash and Judith Eve Lipton recommend embracing just-so stories — even when they entail “mere guessing” — because “the alternative to proposing a just-so story” means the possibility that “God did it.” Design-based explanations are therefore rejected by evolutionary psychologists a priori because of a philosophical bias, not because of compelling evidence.
Critics Within and Without
The field of evo psych has many critics, even from within. Philosopher Subrena Smith argues that evolutionary psychologists cannot merely speculate about why a given modern-day behavior might have provided some evolutionary advantage to our ancestors in the Pleistocene environment of evolutionary adaptedness (“EEA”). Smith argues that evo psych cannot adequately address what she terms the “matching problem”:
[E]volutionary psychological claims fail unless practitioners can show that mental structures underpinning present-day behaviors are structures that evolved in the EEA for the performance of adaptive tasks that it is still their function to perform.
In other words, evolutionary psychologists must establish that modern behaviors (1) are similar to ancient behaviors and (2) are caused by the same neural modules that evolved in the past to program those ancient behaviors. Smith doubts that this can be demonstrated and poses an existential question for her field: “Is evolutionary psychology possible?” She answers in the negative:
Evolutionary psychologists simply do not have the methodological resources to justify the claim that the psychological causes of contemporary behaviors are strong vertical homologs of the psychological causes of corresponding behaviors in the EEA.
How to Play the Game
Most evolutionary psychologists ignore these epistemological and methodological difficulties and accept evo psych explanations provided they fulfil a simple requirement: they must speculate about how a given behavior might have helped our ancestors pass on their genes. To play the game of evo psych, all one must do is speculate as to how a given behavior provided an evolutionary benefit in some situation.
Granted, some evo psych explanations sound plausible. For example, snake phobia could have evolved because it provided a survival benefit to protect us from dangers in the wild. But is that the only possible explanation? Could not a fear of snakes be explained equally well by intelligent design? It would seem a good design strategy to give organisms a survival instinct to avoid dangerous predators.
Or consider this evo psych hypothesis: the ability of children to scream and whine loudly evolved so that they could attract attention when in need or in danger and thus to call others to help them. Again, this sounds reasonable, but why must naturalistic evolution be the only possible cause? Could not a designer find it expedient to give vulnerable members of society the ability to call for help loudly and attract those who can defend them? Thus, if the only goal is to explain the origin of behaviors that help an organism to survive, reproduce, and pass on genes to the next generation, in many cases either natural selection or ID may be a viable model.
A Struggle to Explain Human Behaviors
Evo psych explanations for other human behaviors are less compelling. For example, it is said that laughter evolved from “labored breathing during play such as tickling, which encourage cooperative and competitive behavior in young mammals,” and this led to stronger bonds between individuals in a group. Perhaps, but does this really capture the totality of our experience with laughter? What makes a joke funny? Why do some people have brilliant senses of humor? Can hypotheses like this be tested or refuted?
In some cases, they can be refuted. Raymond Tallis, a former professor of medicine at the University of Manchester, critiques “Darwinitis” — the compulsion to explain everything in Darwinian terms. He illustrates how “Darwinitis” leads evolutionary psychologists to propose persuasive but false hypotheses:
Consider the recent claim that evolutionary psychology can explain why pink is associated with femininity and blue with masculinity. Women in prehistory were the principal gatherers of fruit and would have been sensitive to the colors of ripeness: deepening shades of pink. Men, on the other hand, would have looked for good hunting weather and sources of water, both of which are connected with blue. In fact, in Victorian Britain blue was regarded as the appropriate color for girls […] and pink for boys […] Color preferences are therefore scarcely rooted in the properties of brains shaped in the Pleistocene epoch.
Any Behavior and Its Opposite
Evolutionary psychology is also critiqued because it is not predictive and can explain the opposite of a given behavior as well as the behavior itself. For example, one could imagine that fear of water evolved to help us avoid drowning in certain dangerous situations, like a fast-flowing river. On the other hand, one could envision that the love of water and swimming evolved to help us enter the water when it was advantageous, perhaps to avoid predators or find food. Or one could propose that sharing evolved because doing so would build bonds within a community, perhaps leading others to share their food with us, providing a benefit. But then stealing also evolved to help us get extra food in other situations when that behavior happened to be advantageous.
Almost any behavior and its opposite can be justified under the rules of the evo psych game, leading one to wonder what sort of behaviors the theory actually predicts. As the old adage goes, a theory that explains everything actually explains nothing. Philip Skell, a late member of the U.S. National Academy of Sciences, explained this point:
Darwinian explanations for such things are often too supple: Natural selection makes humans self-centered and aggressive — except when it makes them altruistic and peaceable. Or natural selection produces virile men who eagerly spread their seed — except when it prefers men who are faithful protectors and providers. When an explanation is so supple that it can explain any behavior, it is difficult to test it experimentally, much less use it as a catalyst for scientific discovery.
Evolutionary psychologists have long focused on trying to provide Darwinian explanations for the origin of human moral, intellectual, and religious inclinations — in part because such explanations seem difficult to produce. Former Harvard evolutionary psychologist Marc Hauser believes “people are born with a moral grammar wired into their neural circuits by evolution.” Hauser is right that we do seem to be hard-wired for morality — but a great challenge to evo psych is explaining the origin of humanity’s hard-wired morality, considering that our “moral” behaviors often involve helping someone else to survive rather than benefitting the individual exhibiting the behavior.
Evolutionary psychologists have thus envisioned a myriad of scenarios where it might be beneficial to an individual to help someone else. For example, in kin selection, you help other members of your family survive because they share some of your genes, and in helping them survive, some of your genes are passed on. Or according to the principle of reciprocal altruism, sharing food with others evolved because your friend might share food with you later when you are hungry. This helps you and your kin survive and pass on your genes. Perhaps in other cases, people perform charitable acts in public simply to earn praise and respect, potentially enhancing their own social status and likelihood of evolutionary success. This is called competitive altruism.
Under these staple evo psych concepts, there cannot ever be such a thing as truly selfless love. Instead, it is said that we exhibit “altruism” — seemingly unselfish behavior that is actually programmed by evolution simply to benefit our selfish genes. Yet human behaviors that appear to be truly selfless and “loving” are the most difficult for evo psych to explain.
Specifically, Darwinian evolution has no basis to account for extreme acts of human kindness. Most people who stumble across strangers trapped in a burning car will help them escape — a risky action that promises no evolutionary benefit to the rescuers. Evolutionary biologist Jeffrey Schloss explains how Holocaust rescuers took precisely these kinds of risks:
The rescuer’s family, extended family and friends were all in jeopardy, and they were recognized to be in jeopardy by the rescuer. Moreover, even if the family escaped death, they often experienced deprivation of food, space and social commerce; extreme emotional distress; and forfeiture of the rescuer’s attention. A prime example is Oskar Schindler, the German businessman who risked his life and social status during World War II to prevent the deaths of hundreds of Jews at the hands of the Nazis. Why would he do this if it is the “opposite of saving his genes”? Schloss provides additional examples of “radically sacrificial” behavior that “reduces reproductive success” and offers no evolutionary benefit, including voluntary poverty, celibacy and martyrdom.
The Origin of Religion
Explaining the origin of religion has thus also been a major challenge for evo psych. A popular explanation is group selection, where shared religious beliefs helped fostered group cohesion that aided in survival. But does reducing it to group cooperation really account for the essence or totality of religion? How does group cooperation explain total religious devotion to a deity? When young men or women enter monasteries or convents to pray and serve others, they sacrifice their reproductive success. Why would such sacred religious practices arise in an evolutionary world?
Or consider the religious ascetic who willingly dies at the hands of his worst enemies, believing that his own death will save them. Under an evolutionary view, he has thus become a dead end, yet we hold his actions in the highest regard. How do those behaviors help you “pass on your genes”? Evo psych explanations of religion fail to capture the totality of the religious experience and struggle to explain many religious beliefs and behaviors that are strikingly non-adaptive.
The Alternative: Intelligent Design
It is here that a design-based model seems superior to a Darwinian one. Darwinian evolution simply demands that you survive and pass on your genes. But if human behavior evolved, why do humans exhibit selfless behavior that often prevents evolutionary success? More importantly, if human morality evolved, why do humans universally have internal moral compasses that oddly whisper that selfless love is the “right” option — often whispering the loudest in our most selfish moments?
Many of the most sacred aspects of human life seem tuned not to survival and reproduction but to higher purposes. Our most cherished charitable, artistic, and intellectual activities seem far beyond the demands of Darwinian evolution. Assuming we are programmed only to survive and reproduce, why do we invest so much energy in composing music, exploring the mysteries of the universe through science, worshipping God, and erecting grand buildings including cathedrals and museums?
Of course, intelligence helps us survive, but why would the genius necessary to fly to the moon be required among our ancestors whose only needs were to survive and reproduce in the African savannah a million years ago? Contrary to Dawkins, human beings are not mere “survival machines.” We seem designed for higher purposes.