Robin Marantz Henig recently wrote about the study of the evolution of religion in the New York Times Magazine article “Darwin’s God.” In it Henig states; “According to anthropologists, religions that share certain supernatural features – belief in a noncorporeal God or gods, belief in the afterlife, belief in the ability of prayer or ritual to change the course of human events – are found in virtually every culture on earth.”

How and why did this capacity for belief in the supernatural evolve? What is it about human brains that predispose them to not just be open to belief in the divine, but have it be a common thread in virtually every culture? Henig summarizes the issue this way: Scientists studying the evolution of religion “agree that religious belief is an outgrowth of brain architecture that evolved during early human history. What they disagree about is why a tendency to believe evolved, whether it was because belief itself was adaptive or because it was just an evolutionary byproduct, a mere consequence of some other adaptation in the evolution of the human brain.”

Check out the Evolution of Religion Conference held in Hawaii in January 2007. Both Barrett and Sosis gave presentations. See what all it was all about.

Cogito members started discussing Henig’s article in our Science and Religion forum soon after it appeared (Members, check out the forum here.) Cogito invited Dr. Justin Barrett, a psychologist who is currently a Senior Researcher at Oxford's Centre for Anthropology and Mind, and Dr. Richard Sosis, a researcher in the Department of Sociology and Anthropology at The Hebrew University of Jerusalem, and the Department of Anthropology at the University of Connecticut, to answer your questions in April/May 2007. Each question was answered by both scientists. Read on for a quick summary of the issue.

Dr. Barrett, a byproduct theorist, thinks that belief in a god or gods is a byproduct of several cognitive tools our brain uses to help us survive. Briefly, these tools are: agent detection, the tendency to believe that the motion you see out of the corner of your eye is a real person or animal (priming us to believe in things we can only catch the faintest glimpse of), causal reasoning, the tendency to explain everything using cause and effect (leaving us open to divine explanations when no empirical one seems to fit), and social cognition, the ability to anticipate others’ actions and assume the existence of minds that we cannot see or feel (from which it is a short step to assuming the existence of minds or souls that are unfettered by a body)

Henig puts it this way. “The bottom line, according to byproduct theorists, is that children are born with a tendency to believe in omniscience, invisible minds, immaterial souls – and then they grow up in cultures that fill their minds, hard-wired for belief, with specifics.”

Dr. Sosis, an adaptationist who studies the role of ritual in religion as a way for people to signal their commitment to other members of the group, disagrees. “Far from being an evolutionary by-product, religion represents a critical adaptive complex evolved in response to ecological challenges faced by early human populations,” he said in an article in Human Nature in 2004. He hypothesizes in the article instead, that “the adaptive function of religion is to ensure cooperation when individuals can achieve net benefits through collective action.”

Click the questions below for our interviewees' answers

Instead of saying that we evolved to believe in God, why not say that we evolved to recognize God? It doesn't make sense that the longing for a deity, alone of all other longings, has no natural completion. If we have a tendency to believe in a God, by comparison there must be a God to believe in. Why can't it be that humans, instead of being wired to believe in something, are wired to experience it?

I have heard it said that, because people needed a cause for the things they couldn't control, they created a religion to explain these. Today, science is creating new reasons for natural phenomena. Is it possible that science will invalidate religion? Does the theory that early humans created religion to explain the world around them even make sense?

Is there scientific evidence for or against the existence of an actual god or gods? It seems to me that whether or not a god exists is relevant because the existence or non-existence of a deity will affect the evolution of belief, scientific or otherwise; otherwise you are analyzing effects and ignoring potential causes.

Do scientific explanations of the existence of religion leave any room for faith?

How does one scientifically approach testing the byproduct theory or the adaptive complex theory?

The person who asked "why not say we evolved to recognize God rather than believe in God" seems to think it best to assume the existence of God when explaining the evolution of religion. The person who asked if "there is scientific evidence for or against the existence of God" acknowledges that it is important whether or not God actually exists when explaining the evolution of religion but does not take a position. So which do you think is a more scientific assumption to work with when attempting to craft such an explanation: that a God or gods do exist or that they do not?

In the forums we were discussing if belief in a god or gods was a result of personification - the tendency of humans to assign human qualities to many things that are not actually human. Where do you think this idea fits into the study of the evolution of religion?

While religions have many things in common they also differ profoundly at a philosophical level in ways that are relevant to whether they can make friends with a scientific worldview. Specifically, I notice when people discuss the issue of the compatibility of religion and science, they always talk about religion as a "system of beliefs," and the question is whether these beliefs come into conflict with scientific evidence. But the truth is I think this is a very Christian-centric understanding of what religion is. I myself am a Jew, and as such my religious obligations have to do with what I do, much more so than they do with what I believe. Mightn't we come to different conclusions about the compatibility of religion with science depending on what religion we're looking at?

JUSTIN BARRETT earned degrees in psychology from Calvin College (B.A.) and Cornell University (Ph.D). He served on the psychology faculties of Calvin College and the University of Michigan (Ann Arbor), and as a research fellow of the Institute for Social Research. Dr. Barrett is an editor of the Journal of Cognition & Culture and is author of numerous articles and chapters concerning cognitive science of religion. His book Why Would Anyone Believe in God? (AltaMira, 2004) presents a scientific account for the prevalence of religious beliefs. He is currently Senior Researcher at Oxford's Centre for Anthropology and Mind in the School of Anthropology and Museum Ethnography. Check out his publications here.

RICHARD SOSIS is a researcher in the Department of Sociology and Anthropology at The Hebrew University of Jerusalem, and the Department of Anthropology at the University of Connecticut. His current work explores the relationship between religion, trust, and intra-group cooperation. Other research interests include optimal foraging theory, costly signaling, and the evolution of religion and morality. His primary fieldwork has been conducted on Ifaluk Atoll of the Federated States of Micronesia and Israeli communes known as kibbutzim. Check out his U. Conn website for his research interests and publications.

How did you become interested in studying the evolution of religion?

Sosis: My training is in Human Behavioral Ecology, which is one of the three main evolutionary approaches to the study of human behavior (the others are Evolutionary Psychology and Dual Inheritance or Gene-Culture Co-evolution Theory). Behavioral ecology is the application of the theory of natural selection to the study of behavior in an ecological setting, with particular emphasis on the adaptive features and biological design of behavior. Human behavioral ecologists study human behavior in the same way that evolutionary biologists study behavior in other species, but with particular care and attention to the unique aspects of humanity. Specifically, we examine how ecological variables, broadly defined, can explain variation in human behavior. Ecology is vital to the study of adaptive design because traits are only adaptive in relation to a specific ecological context. Behavioral ecologists think of themselves as biological accountants; they measure the costs and benefits of behavior in order to understand the selective pressures that have acted on human decision rules. Costs and benefits are also measured to determine whether individuals are responding adaptively to ecological conditions. The tool kit of behavioral ecologists primarily consists of simple mathematical models, which are used to generate hypotheses. Hypotheses are tested against empirical evidence and results are used to evaluate, modify, or discard the model.

My work in graduate school focused on the evolution of cooperation. I wanted to understand how cooperation is achieved when individuals have the potential to free-ride. Throughout our evolutionary history, there were likely to have been conditions in which everyone in a group would benefit if they all worked together, possibly to kill a few bison or men in the tribe next door, but individuals themselves could do even better by watching everyone else expending energy and putting their lives at risk. Obviously, however, if everyone pursues the latter strategy, at best there will be no bison for dinner; at worst, your tribe will be decimated by those who figured out how to cooperate. Thus, although everyone may gain if all group members invest in the cooperative goal, attaining such large-scale cooperation is often difficult to achieve without social mechanisms that prevent individuals from slacking off and free-riding on the efforts of others.

After completing my dissertation on the cooperative activities of remote Micronesian fishers, I was thinking about topics that behavioral ecologists had studied – mating strategies, foraging patterns, time allocation, social hierarchies, to name a few. I realized that behavioral ecologists had made significant progress in understanding a wide array of social phenomena, but they had largely ignored one of humanity’s universal and most important cultural institutions, namely religion. I asked one of my dissertation committee members about this surprising lacunae and he attributed it to the fact that many evolutionary scholars were genuinely ignorant about religion and therefore felt uncomfortable studying it. Growing up as a Jew in America and spending considerable time in the Middle East, religion had always been quite visible in my surroundings and it certainly played a strong role in my self-identity, even though my understanding of it was poor. The idea of studying religion immediately intrigued me and discovering the work of two pioneering scholars in the field sealed my fate. While most behavioral ecologists had ignored religion, two notable exceptions were Bill Irons at Northwestern University, and his former student, Lee Cronk, now at Rutgers University. Building on Lee’s initial insights, Bill developed a powerful theory of religiosity as a hard-to-fake signal of commitment. Bill had posited an important link between religion and cooperation; specifically that religion evolved as a social mechanism that prevented individuals from free-riding on the cooperative efforts of others. Upon reading his work, I realized his theory was ripe for testing and that my previous research on cooperation had given me the tools and preparation needed to rigorously evaluate it. I am not sure Bill is aware of this, but I initially disagreed with his theory. Much to my surprise (and at times dismay!), my findings have been quite supportive of his ideas. I have tested the theory employing a variety of approaches, including experimental, ethnohistorical, and cross-cultural methods. For example, economist Bradley Ruffle and I showed that prayer frequency on Israeli religious communes was a significant predictor of individual cooperation, which we measured with economic experiments. In a more recent study with colleagues Howard Kress and Jim Boster at the University of Connecticut, we found in a cross-cultural sample of societies that the intensity of male rituals was positively correlated with the frequency of warfare, which requires high levels of intra-group coordination and cooperation. I have also pursued some theoretical work to refine the theory based on my empirical findings.

Barrett: When I started my undergraduate studies I was interested in religious concepts, particularly how people thought about God. At the time, most all study-of-God concepts concerned how personality or personal history impacted understandings of God’s character or how different God concepts predicted other psychological outcomes and social relations. I wanted to look more closely at the foundational attributes of God that make God a god—not just whether God is loving or wrathful but how do we understand God as all-powerful, all-knowing, and outside of time?

I turned to cognitive psychology for insights into understanding religious concepts. Before long I discovered myself in the beginning stages of a new scientific field, cognitive science of religion, which applies what we know about ordinary human minds to religious thought and action. As evolutionary psychology and other evolutionary sciences have began to dominate discussions about human psychology and mental processes—cognition I became interested in studying the evolution of religion as well.

That said, most of the insights about religious thought and action generated from this field (e.g., how natural, ordinary human conceptual systems bias us toward acquiring religious beliefs) do not have to make any appeal to evolution. If certain features of human cognition turn out to be adaptations or adaptive by-products or non-adaptive, that may be interesting, but understanding why human minds are the way they are is a secondary matter not strictly necessary for developing a scientific account of religion.

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