Followup toRational vs. Scientific Ev-Psych, The Tragedy of Group Selectionism, Evolving to Extinction

Perhaps the real reason that evolutionary "just-so stories" got a bad name is that so many attempted stories are prima facie absurdities to serious students of the field.

As an example, consider a hypothesis I've heard a few times (though I didn't manage to dig up an example).  The one says:  Where does religion come from?  It appears to be a human universal, and to have its own emotion backing it - the emotion of religious faith.  Religion often involves costly sacrifices, even in hunter-gatherer tribes - why does it persist?  What selection pressure could there possibly be for religion?

So, the one concludes, religion must have evolved because it bound tribes closer together, and enabled them to defeat other tribes that didn't have religion.

This, of course, is a group selection argument - an individual sacrifice for a group benefit - and see the referenced posts if you're not familiar with the math, simulations, and observations which show that group selection arguments are extremely difficult to make work.  For example, a 3% individual fitness sacrifice which doubles the fitness of the tribe will fail to rise to universality, even under unrealistically liberal assumptions, if the tribe size is as large as fifty.  Tribes would need to have no more than 5 members if the individual fitness cost were 10%.  You can see at a glance from the sex ratio in human births that, in humans, individual selection pressures overwhelmingly dominate group selection pressures.  This is an example of what I mean by prima facie absurdity.

So why religion, then?

Well, it might just be a side effect of our ability to do things like model other minds, which enables us to conceive of disembodied minds.  Faith, as an emotion, might just be co-opted hope.

But if faith is a true religious adaptation, I don't see why it's even puzzling what the selection pressure could have been.

Heretics were routinely burned alive just a few centuries ago.  Or stoned to death, or executed by whatever method local fashion demands.  Questioning the local gods is the notional crime for which Socrates was made to drink hemlock.

Conversely, Huckabee just won Iowa's nomination for tribal-chieftain.

Why would you need to go anywhere near the accursèd territory of group selectionism in order to provide an evolutionary explanation for religious faith?  Aren't the individual selection pressures obvious?

I don't know whether to suppose that (1) people are mapping the question onto the "clash of civilizations" issue in current affairs, (2) people want to make religion out to have some kind of nicey-nice group benefit (though exterminating other tribes isn't very nice), or (3) when people get evolutionary hypotheses wrong, they just naturally tend to get it wrong by postulating group selection.

But the problem with this hypothesis is not that it's "unscientific" because no replicable experiment was proposed to test it.  The problem is that the hypothesis is, as a matter of prior probability, almost certainly wrong.  If you did propose a valid experiment to test it, I would expect it to turn up negative.

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There are lots of good stories about individual fitness advantages from religion that have nothing to do with burning heretics at the stake.

The emotion of religious faith might just be a feeling of intense admiration originally evolved to be directed at other human beings, but hijacked by religion.

Aren't there clear negatives to being part of a personality cult if you aren't the leader or a senior figure?

Hell no. You can meet people, work together, be a local group alpha (acting like a leader is inherently sexy) and reproduce. Small socialist groups full of young people are at it like rabbits, for example.

An ordinary cult would be a far more effective way to achieve this than a personality cult, though.

Heretics were routinely burned alive just a few centuries ago. Or stoned to death, or executed by whatever method local fashion demands. Questioning the local gods is the notional crime for which Socrates was made to drink hemlock.

These pressures would also strongly select for cheats who simulate faith without having the real thing, leading to a religious form of Batesian mimicry.

Religious mimicry could explain belief in belief, especially for costly beliefs that are weakly monitored or enforced.

...and thus strengthening the "see how many people believe already?" "argument". Alternately, if they are found out, several others - orbiting around No True Scotsman and several kinds of fear.

Also, not Batesian - it's the same species, and it's a lot of risk raising your offspring to only pretend.

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people mean different things things by religion. also, for those looking up the arguments, david s. wilson is the major proponent of group selection-functionalism right now. scott atran and pascal boyer are the major proponents of the cognitive byproduct thesis. i tend to favor the latter. not only do i (and they) think it is a byproduct, but i suspect that religion is produced by the functional constraints of modal human psychology, just like a running engine produces heat. you can stop the heat production if it is turning off the engine. also, i don't think that the byproduct thesis precludes some element of functionalism overlain on top of it...but part of the issue here is that i think religion in terms of cognitive operation is a very different entity than religion as a set of beliefs hooked into an institutional framework.

to be more evolutionarily precise, i'm saying that propensity to religion might be a correlated response of selection for other traits. e.g., agency detection and theory of mind. these are very nifty tools which we humans are pretty strongly hard-wired for. but i think there's a good deal of circumstantial evidence that they breed in us a tendency to imagine spooks all over the place.

This pressure exists once religion is already in place, but doesn't explain why it appears and spreads.

However, selecting for cheats doesn't matter, since they must teach their religion to their children in order to properly simulate faith. Moreover, I suspect that most people who didn't actively choose their religion, but passively accepted it as children don't fully believe it.

Manon, if a number of religious types are just going through the motions (which I suspect is true) then does this help us pin down exactly what benefit religion brings? To me that would suggest the sense of belonging, the tribal instinct.

"...religion must have evolved because it bound tribes closer together..."

I think it's important to bear in mind that unlike today, religion was once pretty much indistinguishable from tribe. Profession of belief in Local Happy Agent was just part of life, not a subject for debate. Socrates would certainly agree, as would Copernicus. It's only comparatively recently that religion has been separate from nationhood or tribe, and its central tenets questioned. The fact that it's still around in a weakened state could simply be analogous to, say, our fight or flight mechanism. Or an appendix.

Eliezer, that's 'accursèd', counterintuitive though it may be. Rare enough for a literature graduate to have any authority around here so I thought I'd speak up! :p

Lots of people think that the main thing religions do is to bind people together. The etymology of the word works that way, right? re-ligio.

If they think that's what religion does, then it's only natural they'd think that's what it gets selected for. No mystery there.

Does it take group selection? People can stay in family groups with kin selection. No mystery. Suppose that people in groups all tend to survive better than loners. That's plausible. Then anything that helps people work together in larger groups (without too many side effects) could be individual-selected. Each individual is selected for the ability to join groups and the ability to maintain them, because the more time he spends alone or in a broken group, the worse his survival. Each individual is selected to correctly choose which others to throw out -- throw out good members sand the group is weakened. Fail to throw out members that will make the group collapse and each individual member is threatened.

It's only group selection when it's religious groups competing against nonreligious groups. It's individual selection when it's individuals in groups competing against loners.

There are similar problems with getting Tit-for-Tat strategies to accumulate in repeated ecological Prisoner's Dilemma tests. If there isn't a subgroup population of sufficient size, it never comes to dominate the population.

Sometimes particles tunnel out of very deep potential wells, is all I can say.

Ben, thanks, fixed.

A just-so story isn't one that cannot be used to generate hypotheses and tests. It's one that isn't used to generate hypotheses and tests.

The best-known just-so story, "How the Elephant Got His Trunk", contains many implicit claims about the nature of inheritance and the origination of traits. It's a just-so story not because these claims cannot be tested, but because neither the people telling the story nor those listening to it have any desire to determine what those tests are or perform them.

It's only comparatively recently that religion has been separate from nationhood or tribe, and its central tenets questioned. The fact that it's still around in a weakened state could simply be analogous to, say, our fight or flight mechanism. Or an appendix.

this is due to the fusion of religion with philosophy and the emerge of super-states which required super-religions. the first religious skeptics emerge in the record precisely when religion shifted from being informal implicit paganism toward a more formal structured system. e.g., the seeds of puranic hinduism, buddhism, jainism gave rise to the carvakas. the mystery religions were countered by lucretius and the epicureans. the religious enthusiasm of the mohists and some daoist groups was countered by the philosophical naturalism of xun zi.

It's only group selection when it's religious groups competing against nonreligious groups. It's individual selection when it's individuals in groups competing against loners.

no. david s. wilson connects group selection with functionalism. so the character of a religion counts, and the character of another religion counts. as a case study think of the syncretistic abangan islam of java, and the more orthodox santri islam of java. the latter is rising in frequency in relation to the former. why? rational choice theorists would argue that the latter is a more appealing product, it offers more goods & services. group selectionists or functionalists would assert that santri islam is better suited to the anomie and dislocation which post-village life imposes upon the typical javanese. if, for example, santri mosques served as a better social insurance system than the village institutions of the abangan one can imagine that over time group level effects would aid the santri. wilson would argue that the santri are a more integrated and efficient 'social organism.' rodney stark, a rational choice theorist, has made the same sort of argument for ancient christianity, suggesting that its self-help ideology and normatively enforced altruism & humanism (e.g., no exposure of babies, helping the sick, etc.) resulted in greater natural increase vis-a-vis pagans. finally, do note that cognitive psychologists tend to record no deep level differences in how religionists conceptualize their supernatural agent of choice, so that's the deeper substrate layer.

There are similar problems with getting Tit-for-Tat strategies to accumulate in repeated ecological Prisoner's Dilemma tests. If there isn't a subgroup population of sufficient size, it never comes to dominate the population.

Sometimes particles tunnel out of very deep potential wells, is all I can say.

lt's separate cultural and genetic dynamics here. on the fine scale level between group genetic variance is simply often weak tea to within group variance, and as eliezer implies 'cheater' strategies are pretty good. in meta-population dynamics when one group exterminates another is it usually total genocide? my reading of the ethnography suggests that usually men kill men and boys. they keep women who are fertile. this means that between group competition results in genetic assimilation of losers via their female lineages. but, it often implies cultural annihilation. the descendants of the sabine women carried their genes, but not their culture (or at least proportionately less of their culture, and no identity as sabines).

how is this relevant to religion? i think it suggests that the case of cultural group selection for religion is viable, but genetic group selection is less so (that is, selection for religiosity on a biological level because of its functional benefits). the conversion of african tribe after tribe to christianity or islam en masse isn't one of genetic replacement by muslims or christians, it is one of flips of group identity.

The selection pressure for faith is almost surely memetic, not genetic. You can focus on the genetic adaptations that it hijacked, but in doing so you will miss the big picture.

Secondly, for understanding religion, I strongly recommend Pascal Boyer's Religion Explained.

Tom, I agree Boyer's book is good, and reviewed it here. See also the work of my colleague across the hall, Larry Iannaccone.

From the New York Times Magazine, March 2007:

Intriguing as the spandrel logic might be, there is another way to think about the evolution of religion: that religion evolved because it offered survival advantages to our distant ancestors. This is where the action is in the science of God debate, with a coterie of adaptationists arguing on behalf of the primary benefits, in terms of survival advantages, of religious belief...

The advantage might have worked at the group level too, with religious groups outlasting others because they were more cohesive, more likely to contain individuals willing to make sacrifices for the group and more adept at sharing resources and preparing for warfare...

When Wilson was a graduate student at Michigan State University in the 1970s, Darwinians were critical of group selection, the idea that human groups can function as single organisms the way beehives or anthills do. So he decided to become the man who rescued this discredited idea. “I thought, Wow, defending group selection — now, that would be big,” he recalled. It wasn’t until the 1990s, he said, that he realized that “religion offered an opportunity to show that group selection was right after all.”

Dawkins once called Wilson’s defense of group selection “sheer, wanton, head-in-bag perversity.” Atran, too, has been dismissive of this approach, calling it “mind blind” for essentially ignoring the role of the brain’s mental machinery.

And much more. source.

Eliezer - who is this "the one" you keep talking about? Do you mean Neo? ;)

I've just read a little on evolutionary psychology and processes, so forgive me if I make an obvious error--I am trying to figure out how one would separate individual selection--choosing for your own fitness, versus selection for the fitness of a group of individuals.

I presumably am trying to bring into the world as many children that can survive and thrive, if I understand right, and this might, and does with humans, imply I am concerned for their well-being, since not being concerend for my infant child's wellbeing hurts my own fitness.

But could it be I am also interested in my brother's fitness, and my cousin's fitness, and so forth, because they have some of my genes? So from idividual traits that favor ones own genes being passed on, one acts in a somewhat group-oriented way (what is good for my children, my brothers, cousins, people who look like me, think and talk like me--assuming they are more probable to have more of my genes than not) et c. Is it that we favor people who are as much like us (physically and in behavior perhaps too--perhaps including belief-inclinations) as possible because they are more probable to be related to us genetically, and therefor helping them helps out own genes pass on and propagate?

mike, for interdemic selection (one form of group selecction) there are models where altruists help the group grow but decrease in frequency over time, but then there is a disturbance where the groups reassort. at this point the altruists are at less an advantage and the groups without altruists go extinct, and the process begins anew as altruist frequencies decrease globally. see d.s. wilson's Unto Others for exposition (or an intro pop genetics book).

Razib, did you mean "at less of a disadvantage" and "as altruist frequencies increase globally"?

Razib, I see you argue that different religions can compete, and what they compete for is converts who perhaps are comparing the benefits the competing religions provide them. Whether individuals make rational choices or whether they irrationally gravitate to the religions that appear to bring prosperity, either way the religions compete.

But I'm talking about how religions could have gotten their start. If people who are predisposed to religion are better at living in larger-than-kinship groups, and if people who live in larger groups survive better, then the spread of predisposition-for-religion can be explained by individual selection without requiring group selection arguments.

The benefits of religion are completely obvious to anyone who isn't completely surrounded by other well-off, well-educated types: it gives people a reason to work hard, behave well, and raise their kids to do the same. The failure of religion during the 20th century under the evil Enlightenment onslaught has delivered large swathes of humanity into alcoholism, degradation, and despair.

Robs, religions tend to thrive among people who work hard and behave well and such. The two tend to go together. But just as priests do well in that environment so do politicians. How can we tell whether these people are helping to maintain the prosperity, or merely parasitising it? In general parasites do better with healthy hosts.

I do not claim that religion is useless. I claim that you are assuming your conclusion that it is not. Ideally we might find some sort of data. We might for example look at examples where people who previously had no religion get proselytised into a religion and see how much better they get at working hard and behaving well and all that. To actually find out we should test our ideas against reality rather than just assuming that our beliefs are objectively true.

I think that before speculating about the selection pressure leading to religion, we should ask whether religion arose as a grass-roots phenomenon, or was usually imposed (or suggested, like a fashion) from the top down. The former case would lead you to expect religion to provide a general selective advantage. The latter only requires religion to provide a selective advantage to the religious elites.

What made me think of this was discussions with a Catholic theologian, which uncovered 4 irreconcilable points between us. All of these points are arguments in which theologians wish to use God as an extralogical operator to get them out of conclusions that are unacceptable to them. Most religious people have never even thought about these arguments, and have emotional reasons for being religious. If religion came from the top down, I might argue that religion is the "logical" conclusion of primitive logic; this argument would not be tenable if religion is a grass-roots phenomenon.

I'm curious... you all have thought about this more than I have, so I'm looking forward to learning... Maybe there isn't a natural-selection benefit to religion. What about the benefit that an INDIVIDUAL gets from espousing religion? Those who do so effectively can be given great power. Or what about religion having the ability to impose order on illiterate and/or unthinking groups? Believing that your sins will be remembered by an omniscient being and that you will sizzle for a very, very long time is an effective way to implement social control. Combine the two -- eternal damnation with "I decide what's damned" -- and you get something very, very powerful.

Thanks, all.

J. Thomas is right. Religion can evolve in primitive man for purely selfish reasons. Group selection may be relevant only for competition between religions. Hence, all the prisoners' dilemma arguments and tit for tat and all that is irrelevant. The vocal heretic is the loner who loses group support and thus has a very difficult time surviving.

So, back in the primitive tribe, surely there were plenty of people who had doubts about their tribes Ugu Bugu god. But as long as one did not wish to get tossed out of the tribe by the chieftain who at least appeared to worship and pray to Ugu Bugu, it paid the individual to go along to get along. All hail Ugu Bugu!

Leaders (and wannabe leaders) invented religion for selfish reasons. They make the people simple enough to believe in literal God(s) afraid of death and hellfire, while as Barkley pointed out, they make the rest of us fear ostracism. But even if you are both smart and know plenty of other freethinkers, religion forces you to waste time and mental energy paying lip service to it, thus (the leader hopes) keeping everyone too busy to plot any kind of rebellion. This idea was already thousands of years old when Hobbes wrote about it in Leviathan.

Religion that is not part and parcel of government is a very new idea historically, and I doubt it will survive much longer, except perhaps as part of some new entity that replaces some of the traditional functions of government (I'm thinking the "phyles" in Stephenson's The Diamond Age).

I read somewhere that if one were to be an x treme nitpicker, a good place for that to occur would be in evolutionary psychology.

I see 'religion' as an expression of intellectual capacity of curiosity rather than the evolutionary event of an adaptive mechanism I'll call the neural ability to be curious.

As to the many why's of the widespread nature of myths (religions) around the planet, all myths were attempts to explain or achieve something.

Of course, rather than curiosity, mabe: 'Well, it might just be a side effect of our ability to do things like model other minds, which enables us to conceive of disembodied minds.'

I think all this faith in evolutionary explanations going on around here is a side effect of our ability to model God.

"Leaders (and wannabe leaders) invented religion for selfish reasons."

This explanation is just plain silly. Judaism, Hinduism, and Greek paganism, e.g., were never "invented" by anyone.

"were never "invented" by anyone" - Dubious claim, Gene.

What is claimed here is that, whether in any way reflecting something real or not, religious practices frequently came into being as particularly effective deceptions. Step 1: convince others you can do magic. Step 2: make yourself less of a target by pretending to be a chosen servant of an invisible dragon. This also ensures obedience even in your absence. Step 3: profit better than any warlord. Step 4: the invisible dragon survives you.

Perhaps we have not evolved to be susceptible to religion as such, but modern religions function as superstimuli to some need which we previously evolved.

Among them, the need to cope with reality, of fall physically ill from depression. I think that counts as a susceptibility.


The "stone the heretic" evolution argument you're making here doesn't really seem to work, because that only becomes a possible state of affairs once 95% of a population is already religious, and by that point, whatever genetic code makes it possible for people to be religious is already basically universal in the population. It may fix the genetic code, but it's not a good hypothesis for how that genotype became universal in the first place.

I could easily come up with more logical hypotheses for a religious mindset being an evolutionary advantage as far as individual fitness goes. For example, perhaps a "religious" mindset is less prone to the "extensional despair" failure mode then a "non-religious" mindset, and perhaps that particular failure mode is detrimental to your chances of surviving adolescence.

I think the beginnings of religion in pre-civilized societies seem quite natural if you put yourself in their places. Their environment consisted of things that behave predictably, like a rock or spear flying through the air, or things that sit there and do nothing, and things that behave unpredictably, like their fellow human beings, animals (more or less), the weather, volcanoes, etc. As it happens, if you try to imagine what other people are thinking, or what they will think if you say or do this or that, that might just be the one area where people, or maybe not oneself, but the wise people in the group might achieve some mastery. The weather -- well, we're still working on that. If is in our nature, when we have mastery in one area and none in another, to hope to make find some analogies from the area we somewhat understand and apply them in the more mysterious area.

So, in these societies you have people explaining every unpredictable thing, and convincing themselves they're actually understanding something about them --- things like weather, disease, floods, droughts, etc, in terms of the volition of some sentient being visible or invisible. Religion goes through all sorts of transformations partly as a result of how the society evolves, and some people discover it is a way to get some control over others by claiming to be more knowledgeable about the mysterious things.

It's really only in the last few hundred years that understanding of things in mechanistic terms finally accumulated enough to give (some) people confidence that maybe that was really the dominant paradigm, rather than the gods, witches, ghosts and other magical beings paradigm, and religion has millennia of entrenchment and institution building, and has come up with such ingenious lock-in clauses as "God will hate you and send you to hell if you don't believe -- believing certain things is labelled virtuous. The idea of trusting institutions of knowledge accumulation by experimentation, and choosing what to believe on the basis of "rational" procedures is still pretty new, and few people have gotten the hang of it. With most people, if they look to science very much for explanations, they are passively accepting what they were taught to do, and they're very succeptable to falling into a belief/social system that makes them feel good in some way.

Yeah, that's one common theory for the start of religious belief; basically, that we evolved a natural ability to both try and predict the future, and to predict what other people would do, and that religious thought and religious belief was a side effect of that, especially for dealing with unusual events that weren't obviously predictable based on what people knew at the time. That's quite possible.

What Eliezer was talking about is an entirely different theory; the theory that religious belief (or some genetic predisposition to religious belief) was actually itself something that was selected for by evolution; not as a side effect of some other trait, but as something that was directly selected for, something that gave individuals a fitness advantage.

I agree with him that the group selection argument doesn't really seem to work here, I just don't think that his theory (the "stone the heretic" hypothesis) makes sense either.

What were the costly sacrifices in hunter-gatherer tribes?

Is killing heretics typical in religions in general, or are theology-based exclusivist religions a relatively recent invention? My impression is that polytheism where it's easy to add gods and customs was the human default for a very long time.

One of the functions of religion-- maybe the main one-- is that it forms an in-group where people are more likely to help each other. I don't know why organizing around fantastic stories seems to be easier than organizing around practical purposes.

I don't know why organizing around fantastic stories seems to be easier than organizing around practical purposes.

IMHO, this ought not be any more surprising than that our taste buds respond more strongly to certain artificial flavors than to natural ones. Once a receptor evolves naturally, I'd expect it to be possible to construct artificial super-stimuli that it responds to far more strongly than to natural stimuli. Humans have certain evolved characteristics that govern how we organize into groups, and we have developed narratives that make use of those characteristics to control how we organize in groups.

Another possibility is that fantastic stories are rightly felt to be more stable than practical purposes. If the important thing is maintaining cooperation, then a practical purpose could be accomplished or go badly wrong, but the fantastic story isn't going away.

Also true. And after a couple of generations, the familiarity of stable centers-of-organization would make them easier to organize around than novel practical purposes.

That said, there are enough practical purposes that were consistent enough from generation to generation during the period that most of our religions evolved that in that case I would expect to see, say, farming exert the same kind of social-organizing influences that, say, Christianity did.

Which maybe it did... I don't really know that much about the comparative roles of farming and Christianity in the social organization of the last couple of millenia.

Eliezer, here is a reasonably probable just-so story: the reason you wrote this article is that you hate the idea that religion might have any good effects, and you hope to prove that this couldn't happen. However, the idea that the purpose of religion is to make tribes more cohesive does not depend on group selection, and is absurd in no way.

It is likely enough that religions came to be as an extension of telling stories. Telling stories usually has various moralistic purposes, very often including the cohesiveness of the tribe. This does not depend on group selection: it depends on the desire of the storyteller to enforce a particular morality. If a story doesn't promote his morality, he changes the story when he tells it until it does. You then have an individual selection process where stories that people like to tell and like to hear continue to be told, while other stories die out. Then some story has a "mutation" where things are told which people are likely to believe, for whatever reason (you suggest one yourself in the article). Stories which are believed to be actually true are even more likely to continue to be told, and to have moralistic effects, than stories which are recognized as such, and so the story has improved fitness. But it also has beneficial effects, namely the same beneficial effects which were intended all along by the storytellers. So there is no way to get your pre-written bottom line that religion can have no beneficial effects whatsoever.

If you mean that the "binds tribes closer together" and related aspects are being grossly underestimated, I agree. The "costly sacrifices", too, may have been poorly assessed - the net effect for individuals, in their true circumstances at the time, may have been frequently positive. Or - this is not to be discounted either - believed to be positive.

"E.Yudowsky declares that attempts to explain religion with evolution are 'prima facie absurdities'" - if that hasn't appeared in the Watchtower yet, it might still. The danger of speaking at all about hypotheses that address only one of the factors in play.

I am not familiar with the claims you're referring to, but I would, instead, draw a parallel between "group selection explains religion" and "mutation explains evolution".