Is Atheism an Evolutionary Adaptation?

Another good title for this post might be, “Over the Top Evolutionary Psychology.”  There can, in fact, be too much of a good thing.  Any lingering doubt I may have had on the matter was dispelled by some links to articles on the “evolution” of atheism at the This View of Life website.  It would seem that a new journal, Religion, Brain and Behavior, has been spawned to “develop, support, and catalyze research initiatives into the manifold functions of religion,” apparently from an evolutionary point of view.  The latest issue focused on “a scientific study of atheism,” a subject of passing interest to me, since I happen to be an atheist.  Reading further in the opening editorial, I found that “Atheism is becoming a topic of fascination for researchers in the scientific study of religion because the naturalness of religion makes atheism unexpected.”

Now it seems to me that I am an atheist because I have devoted some thought to the matter and concluded based on the evidence I am aware of that there is no God.  I think that explanation of atheism should be allowable if one also accepts the fact that the human brain did not evolve merely as a convenient lightweight stuffing material for the skull.  The scientists at Religion, Brain and Behavior, however, are having none of it.  Apparently, rejecting the “moderate” point of view that there is such a thing as human nature, and it is significant, they have gone the Blank Slaters one better.  Dismissing the notion that the ability to reason logically and to distinguish truth from falsehood had anything to do with the evolution of the human brain, they seem to have concluded that everything, or at least everything touching on religion, is a manifestation of “human nature.”  In short, they conclude that both atheism and religious belief are actually evolved traits.

If atheism really is a trait that enhanced fitness, it must have some survival-enhancing function.  In a word, it must be “for” something.  Hence the title of one of the issues main articles, “What are atheists for? Hypotheses on the functions of non-belief in the evolution of religion,” by Dominic Johnson, embellished with a list of no less than 118 citations of other learned authors.  According to Johnson,

Although there was a significant rise in the prominence of atheism after the Reformation in Europe several authors argue that atheists and skeptics were present throughout human history and are common among traditional societies, suggesting that atheism stretches back some way into human evolution.

We are faced, therefore, with the possibility that atheism and atheists have been present throughout human evolutionary history. This sits awkwardly with evolutionary theories that suggest religious beliefs and behaviors are universal, have powerful cognitive underpinnings, and are important to survival and reproduction. How can we square the circle?

Johnson has an elegant answer to this intriguing question:

The key conclusion is that non-belief unambiguously represents our phylogenetic inheritance…

In other words, our primate ancestors were once all too stupid to imagine such things as supernatural beings, so, like lions and tigers and bears, they were all atheists.  Now it seems to me that, besides being unflattering to atheists, this conclusion ignores a rather significant fact.  There is a qualitative difference between lack of belief because of inability of conceive of gods, and lack of belief because of the reasoned conclusion that gods don’t exist.  That distinction apparently hasn’t occurred to Johnson, who charges ahead, citing a laundry list of reasons that atheism may have evolved, such as,

Evolutionary game theory shows that traits often do best when they coexist with other different traits. In many natural systems, this forms an evolutionarily stable equilibrium, with declining fitness returns preventing departures from the right mix of types in the population – so-called “frequency dependent” selection.

The presence of atheists may indirectly improve the fitness of believers by catalyzing their beneficial interactions.


The presence of atheists may force the community to bolster religious doctrine in the face of skepticism.

It seems to me that, if any of these hypotheses are true, atheism must have “evolved” in an awful hurry.  If we exclude the “lions and tigers and bears” variant of atheism for the reasons cited above, the ability to disbelieve in gods must necessarily have followed the ability to conceive of and believe in them in the first place.  Now, unless there were Homo erectus philosophers who discussed these weighty matters around their campfires, one must conclude that atheism “evolved” in a matter of no more than a couple of hundred thousand years, give or take.  For that matter, religious belief itself would have had no greater span of time in which to “evolve.”

Allow me to suggest an alternative to all these interesting adaptive hypotheses.  Religious belief did not “evolve.”  The cognitive abilities of the human brain evolved, until at some point we became capable of wondering how all this stuff around us got here.  When this happened, it must have seemed just as obvious as the fact that the earth didn’t revolve around the sun that it was there because it was created, and by a being or beings much more sophisticated than humans.  Sometime thereafter, deliberate rejection of such beliefs became possible.  Isn’t this, at least, more “parsimonious” than the notion that every human belief must be directly connected with some kind of a “human nature” widget in the brain?

Apparently Johnson doesn’t agree.  As he observes in the conclusion to his article,

Personally, I am skeptical of the main adaptive hypotheses proposed. I favor the null hypothesis of natural variation, in which cognitive mechanisms underpinning religious beliefs vary in whether and how much they generate belief. At one end of this spectrum – one of the tail ends of the distribution – we will have people with very low levels of belief, even atheists, just as we always have extremes of other biological and psychological traits.

In response, I quote a response from one of the commenters at This View of Life.

I suggest that it is essential to distinguish between atheism and anti-theism in this regard. If the object of this evolutionary study is atheism, per se, then we are wasting our time. We may as well study whether or not non-belief in Santa Claus or the Tooth-Fairy is adaptive from an evolutionary point-of-view.  Having said that, if there is an evolutionary basis to non-belief in the super-empirical it lies in the phylogeny / adaptivity of human intelligence and reason.

Rendered into the vernacular, this elegant bit of academic jargon becomes, “Atheism may exist because human heads evolved to serve as something other than ornate hat racks.”  I concur.  I don’t have a particularly high regard for human intelligence, but neither do I have such a low opinion of our powers of reason that I consider them incapable of ever distinguishing truth from falsehood.

Author: Helian

I am Doug Drake, and I live in Maryland, not far from Washington, DC. I am a graduate of West Point, and I hold a Ph.D. in nuclear engineering from the University of Wisconsin. My blog reflects my enduring fascination with human nature and human morality.

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