31-Religious Belief - Robert Sapolsky's Human Behavioral Biology

Let's get started. As we stumble into our next to last lecture, we are looking at one of our strangest topics, I think, of the course after all these other ones, getting to the biology of religious belief. And right off the bat, just as a warning put up here, along the way we're going to be talking about what some people might find to be some pretty disturbing religious practices, and I fell into that category, so just be forewarned.

And what we're doing here is approaching it just like any other aspect of human behavior. We're going to start off examining the behavior, and then we're just kind of mixing all the buckets together with a little bit of hormones, but a lot of brain stuff. And then, with a semblance of familiar structure, we are going to stagger to genes, ecology, and evolution at the end.

Now, right off the bat, right off the bat, I need to emphasize in talking about the biological bases of religious behavior, we're going to be looking at some of it in the context of certain neuropsychiatric disorders. What am I saying? I know you'll see, but what I am definitely not saying is that religious belief is psychiatrically suspect, anything like that. And throughout, keep in mind that while looking at all sorts of features of the biology of religious belief, there's just as much biology going on with people who are incapable of religious belief, who have lost it. And it's simply, there's a whole lot more religious people than non-religious ones. So, we know much more about it. Okay.

So we start off with behavior. And right beginning there, we see the absurdity of talking about religious behavior. So much so that we're going to be done with a topic in a mere seconds because of the variability. It's been estimated there's more than 10,000 different religious traditions that have been invented on this planet, about 6,000 languages. So that gives you a sense of that ratio. So there's all these different forms of religion. And then there's people who are spiritual but not religious. And then surprisingly, there's heterogeneity among people who are atheists, and different ones who are atheists but they're really like whatever apatheists is the term given for it. All sorts of whether people get to their atheism through intellectual processes or emotional ones, all sorts of subtypes of atheism. So everything we're looking at here is going to be ridiculously smoothed out in terms of this is one of the more variable outposts of human culture.

Now, a theme I already said that's going to run through much of this lecture is, in lots of instances, in some thoroughly fascinating ones, religion offers sanctuary to people who otherwise would be peripheralized, troubled, impaired in their daily functioning because of some sort of neuropsychiatric disorder. And what religion repeatedly does is not only give them sanctuary and protection, but incorporates whatever their problems are into the religious practices.

So we start off. The very first one takes us back to our last lecture, what we were left with at the end, schizophrenia. And at the end, we got to the evolution of schizophrenia. No other species has anything that looks like it. And are there any downsides to it? Yeah, decreased reproductive success, shortened lifespan. Are there any upsides evolutionarily? Some indication that individuals with schizophrenia have a lower risk of cancer. But what I noted at the end is there may be one major advantage evolutionarily floating around here, and it doesn't have to do with schizophrenia, but something related to it, which takes us back to this whole world of medical genetics where a full-blown version of some sort of genetic disorder is a disaster: homozygotic. And a partial version, heterozygotic, is actually advantageous. And the textbook example, sickle cell anemia: full-blown version, blood disease that is a disaster; partial resistance to malaria, a whole bunch of these. And there's a possibility that schizophrenia and its evolution can be thought of in that context.

Now, this goes back to that classic work by Seymour Kety, trotting this out the third time, though. This was the Danish adoption study that they did with every case in Denmark, or whatever Scandinavian country they wound up in, looking at whether there was or whether there was or wasn't schizophrenia and the adoptive family and the biological, and we know this whole thing. And the number nine was the first screaming evidence of a genetic component to schizophrenia. All you've gotten from your biological mother is genes. We know that's not really the case, but nonetheless, this being a whopping big vote for a biological component to it. Okay.

So, how did they carry out that study? That took them years to do. Kety and a small team of researchers went over there and they went through, as I've said, every single adoption case that existed in the country at that time, being able to access records of who were the biological parents, adoptive parents, and spent years interviewing all these people, interviewing biological relatives of individuals with schizophrenia, adoptive relatives. And in the process, they had done something unique. Take your average, I don't know, psychiatrist who works with people with schizophrenia, and I don't know, 10 patients, 20, whatever over the course of the year. If they're young, a couple of times a year you'll meet with their parents for a progress report. And what these guys had done instead was, in the process of doing this for years and years, they had just talked to more relatives of people with schizophrenia than anybody had ever done before, because they were going through hundreds, thousands of cases. They just had the largest exposure to close relatives of people with schizophrenia ever. And they noticed something interesting. They noticed that not every single family member of somebody with schizophrenia, absolutely nothing remotely like that. But at a higher than expected rate, a lot of these relatives were like a little bit weird, a little bit off. People could be a little bit off in the exact same way and not have a close relative with schizophrenia. Not every relative of people with schizophrenia shows this profile, but at a way, way higher than expected rate, some sort of odd features. And when you look at them, they wind up being kind of a mild version of schizophrenia, what has come to be called schizotypal personality. And people debate whether it should be called schizotypal personality or schizotypal personality disorder. Is this a disorder? Is this a quirk? Is this an idiosyncrasy? It's people who are perfectly normal but are kind of odd in a number of fairly consistent ways. Odd perceptions. They will report feeling a presence of someone in the room when they're in an empty room, things of that sort. Social withdrawal, very socially disconnected. Two classic professions of schizotypal individuals: one is you're up on top of a fire tower watching over mountains looking for forest fires, and you're by yourself 24/7. Or you go into a movie theater, and in the back there, there's the person running the film, or whatever, who sits there in the dark all day, tending towards occupations that were extremely solitary. Social withdrawal, mild concreteness, concreteness along the lines of domains that most of us would see as parables, uh, metaphorical, whatever, they take literally. For example, just to show you where we're heading, very literalist, concrete interpretations of the Bible. The world really was made in seven days. It is really possible for someone to have walked on water, to have turned blood into wine, whatever it is that went on, that these were not just instructive metaphors, parables, but quite literal. Mild concreteness along those lines. Finally, the really interesting one is what came to be termed metamagical thinking: just being really interested in like, you know, kind of borderline suspect stuff like horoscopes or extrasensory perception or UFOs, or people who were really, really, really into their science fiction, fantasy, whatevers, and cosplay, and go off to these Star Trek conventions, and all of those. This is not a mental illness. Going to a Star Trek convention is not a sign of a mental illness, nor any of these. It's just sort of an odd, quirky personality that has some resemblances to schizophrenia, but a milder version of all of these, and thus termed schizotypal personality.

So looking at this, the question becomes, who are individuals who were schizotypal? And it turns out almost a hundred years ago, an anthropologist named Paul Radin gave what I find to be very convincingly the answer to that question. Radin studied northwest Native American populations and wrote various dictionaries and stuff, and like a very accomplished anthropologist. And Radin at the time began to talk about how in lots and lots of traditional societies, indigenous cultures, there would be an individual who he would call "half crazy." Half crazy. Who was he talking about? Shamans. This made perfect sense. In lots of cultures, shamanism is about tricksterism, things of that sort, sleight of hand, and things like that. But in lots and lots of cultures, what are shamans? They go into trances. They talk to the dead. They turn themselves into a hyena during the full moon. They sojourn alone, living for days and days in the desert, and then come back with the good word, things of that sort. Shamans in culture after culture are shot through with metamagical beliefs and actions and often social withdrawal. And what you see there is shamanism has been around forever. And there's been this whole thread of anthropologists noting this. One anthropologist, George Devereux, talking about shamans as being healed madmen. Another anthropologist, Devereux. This was mostly in the 1930s and 40s, talking about how religion is organized schizophrenia and schizophrenia is personal religiosity, talking about shamanism as a root of all of this. And this winds up, for my money at least, and lots of people at the time, making a ton of sense.

Now, one of the all-time grand pooh-bahs of anthropology, this guy Alfred Kroeber, had something really interesting to say about this. He was one of the dominant anthropologists of the early part of the 20th century. Incidentally, anyone who is a science fiction fan and reads and adores Ursula K. Le Guin's writing, Ursula K. for Kroeber, she was the daughter of Alfred Kroeber, which probably explains the very anthropological and zoological tint to a lot of her writing. In any case, Alfred Kroeber, early in the last century, was considering this whole issue of people who were psychiatrically suspect, half madmen, healed madmen, half and associating it with shamanism. And he wrote a really interesting essay called "Sanction or Sanctuary," where the whole point of it is, in culture after culture, as we heard last week, people who are mentally ill, people with schizophrenia, are peripheralized, are out-grouped, or mistreated, or persecuted, or all of that, including people with milder versions. And he's emphasizing that in lots of indigenous religions, not only is religiosity there a place of sanctuary for individuals with a personality profile like this, but in fact is sanctioned. It is celebrated. Amid people with schizophrenia having a decreased reproductive success, in culture after culture, shamans are proclaimed. Shamans are powerful members of society. Shamans often have very elevated reproductive success rates, all of that. So this argument all along, saying this is a traditional role filled by people with schizotypal personalities.

Now, Kroeber made this very, very clear distinction, which comes down to, for example, this quote: "In general, the psychopathologies that get rewarded among primitives are only the mild and transient ones." And he at one point said, "Yes, yes, uh, you know, it's great having shamans, but society is ill-served by somebody who 24/7 believes that he is a tree." And a great example of this, Kroeber mostly studied North Plains Native Americans. And he was at one ceremony once, and with the sort of informant there, and watching it, and it was this shamanistic ceremony, and the shaman was this frothy, amazing, over-the-top, all sorts of histrionic stuff going on. And at some point, the informant leaned over to Kroeber and said, "Wow, can you believe our shaman? He's like the best. Nobody does these rituals like he does. He is just over the top with all of that. We are so lucky to have him as our shaman. But thank God we don't have two of them." And what we just saw is cultures could deal with a certain number of individuals like this. You don't want half the population to be shamans. You want people to speak in tongues during religious rituals. You don't want them to speak in tongues in the middle of the quiet moment of a hunt or something like that. It is partial. It is controlled madness in the terminology they gave there. Kroeber, by stating it in terms of these are people whose psychopathologies are mild and transient, who are hearing voices at the right time, what he just defined was schizotypy, half a century before the word even came to exist.

So you look at that, and what that begins to suggest in traditional human cultures, we've got the same kind of heterozygotic, homozygotic argument that we've seen in other cases. Heterozygotic, you got the shamans. Shamans, like every culture has come up with shamanistic individuals and celebrated their metamagical stuff, and all of that. And if the price is, if the homozygotic price is every now and then you deal with a cousin with what we would call full-blown schizophrenia, the trait is carried along by the adaptiveness of the partial version. That is the argument that comes out of that for the evolution of schizophrenia. There has not been selection for genes pertinent to schizophrenia; there has been selection for milder versions of those genes with schizotypy.

Okay. So what about in the West? What about in the West? And you notice we already heard from Kroeber's quote the word "primitive" pop up. Hackerneck in the '30s was probably the most leftist anthropologist of this whole time period, which is to say he was not a flaming racist, unlike sort of the backbone of anthropology then. Hackerneck was outraged at words like "primitives" and things of that sort, and saying like, "How dare we, how dare we, sort of, uh, you know, be offensive about their religions, and traditional cultures, saying that they are mired in the irrational." No, they're not irrational. They're serving a purpose for them, all of that. And his argument was, you can't make that distinction between Western culture and indigenous traditional ones. And my view is you can't make that distinction either, but for a different reason. Yeah, traditional cultures, shamanism, and their religions are totally irrational. And religiosity in the West is totally irrational as well. And we will see sort of the formal definitions of that, of how it fits. It's been sort of people at the time saying our culture is unique in having banished irrationality. That might be a little bit over-optimistic there.

Here are some recent statistics from a poll looking at Americans, American adults, American adults who are allowed to vote and drive motor vehicles, and things of that sort. And what did this recent poll show? 25% of Americans say that they believe in ghosts. 36% believe in mental telepathy. You can project your thoughts into somebody else, or pick them up. 47% believe that not only are there alien life forms out there, but they have visited us, and there are UFOs. And more than half of Americans believe that the devil is not a metaphor, that the devil is a literal being in some version of flesh and blood. We have not banished the irrational in Westernized cultures. We have instead celebrated it forever. In some cases, the metamagical irrationality of the West is fairly recent. This is like some new age, "nouveau peasant" belief stuff with hot tubs, or who knows, things like that. But in lots of cases, instead of this fast-food spirituality, it is metamagical thinking that is stretched back for centuries, for thousands of years, have legacies all throughout our history. And the West has been mired in metamagical thinking, in the form of Western religions. And just to put that sort of in perspective, it is not normally a sign of robust good mental health to report that you hear a voice coming out of a burning bush. To report that you just spent the night wrestling with an angel. To report that you just had a conversation with someone who died a few days ago, and you encountered them walking around. Where did these notions come from? Where did the idea come that the world was made in seven days, or that when snakes are talking to you about apples, be careful because they're up to no good? These were not made by committees. These were made by schizotypal individuals who were immensely influential and wound up supplying the metamagical thought for their whole culture for centuries, for millennia afterward.

Now, of course, this brings us back to Kroeber's point. You don't want somebody who always thinks they're a tree. You don't want somebody who is bursting out in glossolalia in the middle of a quiet part of a hunt. All that. You want to control it. You want it partial. It is controlled madness in the terminology they gave there. Kroeber, by stating it in terms of these are people whose psychopathologies are mild and transient, who are hearing voices at the right time, what he just defined was schizotypy half a century before the word even came to exist. So you look at that, and what that begins to suggest in traditional human cultures, we've got the same kind of heterozygotic, homozygotic argument that we've seen in other cases. Heterozygotic, you got the shamans. Shamans, like every culture has come up with shamanistic individuals and celebrated their metamagical stuff, and all of that. And if the price is, if the homozygotic price is every now and then you deal with a cousin with what we would call full-blown schizophrenia, the trait is carried along by the adaptiveness of the partial version. That is the argument that comes out of that for the evolution of schizophrenia. There has not been selection for genes pertinent to schizophrenia; there has been selection for milder versions of those genes with schizotypy.

Okay. For example, Charles Manson was diagnosed with schizophrenia long before he like burst onto the national consciousness in the 1960s. All of you are way too young to know about him. Another one, Jim Jones, led Jonestown in Guyana. It led to this mass suicide of almost a thousand people with this religious group that he had founded. And he had been diagnosed with amphetamine psychosis. Oh, that takes us back to the schizophrenia lecture. I left that out. That whole thing, you block dopamine receptors, and schizophrenic symptoms become less. I bet you there was too much dopamine. Dopamine hypothesis: Do the opposite. To take someone who is not schizophrenic and give them a drug that releases excess dopamine, a drug like an amphetamine, and they begin to look psychotic, an amphetamine psychosis. Somebody comes into an emergency room, and they're tangential and hallucinating and all of that. And if you pump their stomach out and suddenly they start making a whole lot more sense, it was probably amphetamines rather than schizophrenia. Okay, so Jim Jones, diagnosed with amphetamine psychosis, when it is taken too far. These are like disastrous cult movements that are splotched in all sorts of madness. But get it right. Get it right to the exact perfect extent and do it in the right place and time. Get this schizotypal stuff just perfect to fit what is needed at the time, and with any luck, for millennia afterward, people won't have to go to work on your birthday.

So I think what we see here is the beginning of this notion of one domain where religiosity in the form of metamagical thought, metamagical belief, all of that, providing a sanctuary for what otherwise is someone sitting alone in a projector booth. This gives you sanctuary, and it sanctions what you're doing, and it elevates this, and celebrates it in lots of circumstances.

So another domain in which this comes through, thinking about sort of what the backbone of religiosity is, and much of it is sort of the, the steel superstructure of religion, is, is the large sort of abstract thoughts as to how you go about deciding: Is there an afterlife? Is life sinful or otherwise? Is there a purpose to be here? What is our responsibility to all of that? And lots of religions summarize into these sort of conceptual notions: there's the Holy Trinity, "I am that I am," "There's no god but Allah," all of that. So a lot of religiosity is built around that stuff. In these current times, a lot of religiosity is built around something that is still relatively recent: the notion that religiosity is about community, about pro-sociality, about good acts. But all throughout, there has been another thread going through religious belief of the highly orthodox, highly fundamentalist religious among us, which is the importance above all else of rituals and ritualism.

Now, to begin to appreciate that, we look at our next sort of neuropsychiatric disorder, and this is one that like lots of us are familiar with and have elements of or certainly know people with, OCD: Obsessive Compulsive Disorder. Obsessions: thoughts that won't stop. Compulsions: actions you cannot prevent, actions that compel you, that you have to do, and you have to do often in wildly maladaptive ways. Okay, all of us have elements of this. My guess is most of you are too young to have ever had the experience of going to a mailbox and actually putting a letter in there. Instead, you just like hit send and it goes off. Back in the old days, you'd have something really important, like an application or some checks or something like that, and you go to the mailbox and you like put the letter in the mailbox, and you check to make sure it goes down, because it's important. And you check again just to make sure that it's not stuck there on something. And you begin to, but it's probably, you know, it couldn't hurt to check once more to see if it really went down. And you start walking away. What if there's a hole in the bottom? And before you knew it, you're on your knees looking underneath. And we would all do stuff like that. Actually, maybe we didn't all do that, but I certainly would if it was important enough. Just getting caught up in this ritualism of that at a very particular time.

Here's another example of this. Okay, here we have two satellite photos. And this first one, this is a picture of a tray of Rice Krispie Treats. And this is what it looks like after any of us is left alone in a room with that and a small knife. We all cut off this edge and eat that little piece. Why do we do that? Because we think eating just a little piece doesn't count as cheating on our diets. Or are we thinking it'll be fresher if you minimize the amount of like interface with air? No, it just feels like weird having this little piece sticking out, and you just got to smooth it out. We all have that impulse at that time, and we trim it off. And this is remarkably common, and this is not a psychiatric disorder, obviously. But then there's the world of people for whom these impulses, these obsessions, these compulsions take over your entire life. To get a sense of what goes on with somebody with full-blown OCD, which falls into a category as destructive to your everyday functioning as a major depression, as schizophrenia, all of that. What's one of the most common things at the top of the list? Washing, cleansing, purifying yourself. People with serious OCD will spend five, six hours a day washing their hands in rituals, enormously ornate rituals. You first do a cleaning in water of a particular temperature that you have to check with a certain type of soap, and then you can dry your hands with a certain specified towel. And then you do a second washing at a different temperature, with a different type of soap, then a different type of antibacterial something or other. And you go through this whole sequence, and an hour into it, finally, finally, finally, you are clean. And inevitably, as you're stepping out of the bathroom, your elbow hits the door, and you've just gotten soiled, and you got to go and do it all over again. People with severe OCD like this cannot hold down jobs because they are gummed up with rituals like these for hours and hours every day. Hours of rituals built around food preparation, about having symmetrical stuff, utensils symmetrical. You can't start on an assignment until your pens and pencils are perfectly parallel with each other. You are driven to distraction if there is some sort of asymmetry around that you can't fix. And the whole point of these is, this is not just quirks. These are people whose lives are ruined by this disease. And that was a remarkable recognition when people began to, you know, view OCD as a separate psychiatric disorder, that you can have your life destroyed by things seeming so sad you can't get out of bed, or being so thought-disordered and you're hearing voices that you can't put two coherent sentences together. But your life could also be destroyed by this sense that you got to wash and wash and wash, and it is never enough, and somehow you always get dirty again.

When you look at OCD, there is a structure to the compulsions. Number one, as I said, on the list of every culture out there with OCD, way at the top of the list are rituals of personal hygiene: washing, ornate rules about it, ornate sequences, things that you feel soil you and trigger you having to start the process all over again. Second most common category of compulsions: ones related to food safety, food purity, food purification, food prohibitions, all sorts of things that you do built around that. Third most common: ritualistic compulsions built around when you are entering or leaving a place of significance. You have to have walked a prime number of steps before you could enter the building for a job interview. That's one of the ones that comes up. You're finally taking a chance on going out and getting a job, and you know, you just know it's not going to work out right if you do anything other than walk a prime number of steps to get to the front of the building. And if you didn't pull that off, or if it felt like you kind of cheated, you got to go do it again and again and again, and you never show up for the interview. Rituals of entering and leaving places of emotional significance. And number four on the list: numbers, numerology, compulsions about you have to do something a certain number of times before you could pick up the fork. You have to tap it X number of times on the table, things of that sort. And these are the most common compulsions in OCD.

So, how do we make sense of OCD? The person does not have insight. They do not say, "Help me. For some reason, I need to wash my hands six hours a day." They say, "Help me. For some reason, I can't get clean." There is no insight into it in lots of cases. And what you see is, not surprisingly, OCD is categorized in sort of a psychiatry Bible as a subtype of an anxiety disorder. It's this free-floating, permeating anxiety, dread. Dread of what is menacing all around you. And if you do the rituals just right, if you enter the right number of steps, if you pull this off, if you've been clean enough, if you do, you can hold off the dread. And it always proves to be temporary because it always comes back. Psychiatrist Judith Rapoport, who wrote a great book 30 years ago, um, case studies of individuals with OCD, I think the book was called The Boy Who Couldn't Stop Washing, had a metaphor, a metaphor straight out of everything we know about a fixed action pattern. Lots of us recognize the fixed action pattern of when a dog is getting ready to go to sleep. It goes over to its blanket or its pillow or whatever it is, and it circles around, sort of patting it down. And then it circles around some more, and then it's about to settle, and then it does a little more circling, and then a few more times it maybe once, and then finally settles down. In Rapoport's view, OCD is the dog circling the blanket who could never, ever stop. It can never, ever feel as if you have kept that dread permanently at a distance. You've only held it off. You've only held off the anxiety for a while.

So, where does religiosity come in? Like, there's all sorts of ways of being great at religion. You could do wonderful works. You could be a religious leader that takes the form of being a military leader at the front of a crusade. All sorts of versions. But then there's a whole world of people who are really good at their religion insofar as they are really good and ornate and devout and orthodox and fundamentalist in the carrying out of rituals. So just to give a sense of it here, we'd have four of these like world religion ones. And what we see, okay, in the first one, if you were going to be in the upper strata of religion, and this particular religion honored all of that, what's involved is you have six hours of handwashing and body washing a day. There are rules as to the first sight you're supposed to see in the morning, which foot first steps outside in the morning. There are rules about what direction you are facing when you're sitting on the toilet. There are rules when you are doing certain rituals as not only the number of breaths that you take, but the ratio of one nostril that you hold closed and then the other nostril, rituals of the ratios of washing the left hand and the right hand, stuff like that. There's a magic number. The number 24 is considered magical in this particular religion. There's food prohibitions which could be defined as a food which is absolutely palatable and a totally reasonable source of nutrients, like during a famine, and sacred values that people would starve to death before they would eat this. So a whole bunch of these.

So another one of these religions. What's going on? This one has all sorts of rules. I think washing 12 different times in the day, that there's a whole ritualistic thing that when you enter or leave a place of emotional significance, a gesture you're supposed to make at the doorway. There's food prohibitions out the wazoo. And in much the same way of sacred values, people will starve to death before they violate these food prohibitions. There's all sorts of magic numbers. There's the magic number 18, which is full of significance. There's a really interesting magic number in this religion: the number 613. What is 613? Those are the number of rules you are supposed to follow each day in order to be a devout, observant member of this religion. 613. What is that about? And you will notice it consists of two numbers. The first one is the number of days in the year. And at the time that this was first invented, what people thought was the number of bones in the body. How many rules are there each day to please your deity or deities? Well, it's the number of days of the year plus the number of bones in the body. It happened that these are things, 248 that you have to do, 365 that you have to avoid doing each day, which led one sage to say, "Well, since it is so easy to inadvertently sin more in this domain than that, it's better that we hadn't been born." Here's the evidence that this is about the numerology. It is about the ritual number rather than the content itself. For centuries, people have been arguing over what are the 365 things you're not supposed to do and what are the 248. The actual content doesn't matter as much as the notion that your deity or deities want you to make sure you avoid doing as many things as there's days in the year and do as many things as there's bones in the body and the numbers for their own sake. There's ritualistic hand gestures that you see among the elite in this religion where they signal to each other. They display that they are of that upper stratum.

Next religion. This one. This one involves, okay. Once again, washing rules about how many mouthfuls of water you take to wash out your mouth and spit it out in the morning. Sequences of which hand you wash first, followed by which other one. There are rules as to the first food you're supposed to eat each day. There's rules of ritualistic things when you enter or leave a place of significance. There's rules out the wazoo about what you are supposed to do when you are going about your personal hygiene. Food prohibition, same thing again. Ornate, completely irrational. Taking people who, like in every one of these, has been circumstances where people have been seriously starving. Yet this food prohibition would be way at the top of the list of things you were supposed to stick to, and its own set of magical numbers: 7, 10, and then multiples of both of them. What else?

Now we have another religion, another major one. And there's number of prayers, number of prayers for this occasion, for that occasion, for depending on what you've done, depending on what you haven't done. You are told the number of prayers you need to make. There's ritualistic hand gestures that are made when you enter a place of significance or leave it. You are supposed to make these gestures. The number three is considered magical. There's all sorts of food prohibitions, and there's all sorts of rituals around eating ritualistic food. What are all of these looking like? These are all looking like the rituals of obsessive compulsive disorder. These are Hindu Brahmins. These are Orthodox Jews. These are highly observant Muslims. And this is mostly Catholicism with a mixture of some other Christian sort of rituals in there. What do we see in all these cases? These are exactly the same things as in OCD. You look at the most common religious rituals out there, and they are about cleansing, self-cleansing, and purification. The second most common about food purification, food preparation, food prohibitions. Third most common, ritualistic things you are supposed to do when entering or leaving a place of sanctity. Fourth, numerology. And these religions, if you are going to be a devout person in any of them, at the highest level of asserted orthodoxy, your life is consumed with this. Six hours a day of washing. All sorts of rules as to how many hours you have to wait after eating one type of food and another. If you like soil one of your utensils in the process, how many months it needs to be buried in soil to become cleaned, all of that. What we see is it's the same business. It's the same sequence. It's the same hierarchy of ritualism as in OCD.

Now, where we're obviously heading is the notion that religious ritual in this case gives sanctuary and sanction for people whose lives might otherwise be completely taken over and destroyed by their pull towards ritualism. Now, all sorts of people have noted this. People in the secular world. Freud, for example, said that obsessive religiosity is like an organized, no, what was his exact quote? "Obsessional neurosis is an individual religiosity, and religion is a universal obsessional neurosis." Okay, that's saying what religion is about is sharing the rituals. Okay, Freud: snide, dismissive, secular, all of that. Throughout the centuries, religious leaders have recognized the exact same thing. Um, a sixth century monk who was writing about how prayer doesn't count if you're not concentrating on it. If you're not thinking about it, if you're just doing it by rote, it doesn't count. 15th century Ignatius of Loyola, when he was training new priests, said, "Be on the lookout for people who would be giving their prayers but were showing scrupulosity. All they were doing was doing the rituals for the ritual's sake." And what you're supposed to take them aside and say, "God doesn't care how many times you say this. God cares that you are thinking about this, that you are feeling it. Be on guard against people who are doing this stuff just out of mindless rote stuff."

This is not a mental illness. What it is, again, is a source of decreasing anxiety. Rather than a nameless dread, the dread gets a name. It gets a name. It is Lucifer. It is some such thing. It gets a name, and it comes with feeding instructions as to how to keep it at bay and how to please your Lord who is going to help you keep it at bay. And most importantly, it's shared. It's you and the other co-religionists. It's how you collectively keep that anxiety at bay. It's how your ancestors have been doing it for centuries. It's an enormous source of comfort in that regard. You give it a name. You are given very strict rules for how to keep it at bay. And finally, finally, unlike most people crippled by OCD, you're not alone. You're sharing this stuff.

Now, this brings up sort of a second level way of appreciating this. So, who are the great religious leaders? They can be great thinkers or metamagical, or they could be social revolutionaries, or they can be military leaders, all of that. But what this introduces is there's another way to be a religious leader, which is to be really good at rituals. Because if done right, you can make a living being religiously ritualistic. In traditional Hindu belief, among Brahmins, there's a prayer, the Gayatri prayer, that you are supposed to say 2,400,000 times in your lifetime, a multiple of this sacred number. And if you are a wealthy Hindu and you're getting on in years and you haven't quite gotten enough of these done yet, you can hire a whole bunch of Hindu priests and they come and you set them up in your backyard with a big tent and you feed them all the time and you hire them to do the 2,400,000 prayers for you. You can get hired to pray for somebody else in a ritualistic way. In Judaism, you could be a rabbi with kosher law, with orthodoxy, where you sit in a food preparation factory, and you're not preparing food. You have nothing to do with it. Your entire job is to watch to make sure that other people are preparing the food in a ritualistically acceptable way. You make a living doing that. You make a living in all sorts of... you get priests who come and bless convocations. And you say, "Oh, no, but that's not really their job. I mean, this is part of who they are." And you reflect on it, and in all these cases, these are people who are having jobs. They're getting health insurance. They're getting retirement accounts or something when they step down from being the rabbi, making sure that like the tofu dogs would bring a pleased smile to the lips of Abraham, or something that is being prepared in the right way in this factory. In all of these, you could make a living at being really good at religious rituals.

And then we begin to get some insight into this remarkable piece, this historical document about this 16th century monk. This monk, he was, what was he? He was an Augustinian monk named Luther. And Luther, by all reports, had had a fairly difficult life. Um, he was known to have had a brutal, terrifying father. A father who, the records indicate, was arrested on one occasion for having murdered somebody in a fight. A terrifying father. Our Luther grew up anxious, hypochondriac, filled with all sorts of dread. At one point, he was out walking across a meadow and a thunderstorm came up and he had a panic attack, and he at that point prayed to God and said, "If you let me survive this thunderstorm, I will devote the rest of my life to you." And he survived the storm, and he became an Augustinian monk, and he threw himself into it like crazy. He took vows of silence for days on end. He would repeat the same prayers over and over and over. The first time he led a mass, what was supposed to be, I don't know, half an hour long, it went on for four hours because he kept deciding he had stumbled over a word or he had said a word without thinking sincerely enough about it, or and had to start all over again. He had all sorts of his seniors, his like mentors, saying, "You know, this really isn't the point. The point is like you should be thinking about it." And this one remarkable thing, his father confessor, this man who in the 16th century was just phenomenally psychologically insightful, one day this monk, Luther, was sitting there and going through his confessions. Like, there's a lot to confess about, you're a monk living in a monastery. But he's going on and he's saying, "Oh, God is going to be so angry at me because when I said this prayer, my mind wandered at this point." And then later in the day, "I had this thought that was blasphemous, and God is going to be so angry at me about that." And "God is going to want to punish me for this or that," and "should be angry because I did this ritual." And at one point the mentor said, "I have no idea what the case is going on here with you, but God is not angry at you. For some reason, you are angry at God." Which was a phenomenally insightful statement. This guy eventually like summarized everything that like closed the case on what was going on there. A quote of his: "The more I wash, the dirtier I get." Why do we know so much about this individual? Because he happened to change all of history. This monk, known in German as a "Lutter," was Martin Luther. And he took his ritualism in all sorts of directions. And finally, instead of just being angry at God or his murderous father, he wound up being angry at another father figure, and Europe has never been the same.

So we look at these, like, who invented these rituals? Who invented knocking on wood? Who decided that they had a thing about the number 24 or the number seven? Why would you suppose that God is really, really worried about the number of bones in your body and how many things you make sure you do each day to match that number? Where did these come from? Once again, they didn't come from committees. They were coming from people, I believe, struggling with OCD. So there's two explanations. Why is it that the list of the most common religious rituals perfectly match the list of the most common rituals in OCD: self-cleansing, purification of food, entering and leaving, numerology? Well, you can have a convergent argument saying, "Well, yeah, of course you're going to have a lot of rules in any of these cases about like you need to keep clean, just personal hygiene, and you sure don't want to consume food that's poisonous, all of that." The alternative is that throughout history, the people who struggled with OCD and wound up being able to do it in a religious context, and at some point there was some crisis, some moment of great duress for you and your co-religionists, and that's the point where you release the secret. The secret you have had all these years, all these years: "This is how I please our Lord." And it catches on, and it becomes copyrighted and made in multiple copies on a conveyor belt. And soon it has become the ritual of shared dread throughout everyone who is a co-religionist. And this is built around the frequency with which religions view the body. The body as a place where you test your faith, where you prove how devout you are by doing something difficult with your body, by doing something damaging to your body. Self-mutilation, self-flagellation. And religion after religion, including all of these, have rituals where people beat themselves bloody. They whip themselves bloody. They pierce their fingers with things. They pierce their cheeks with a knife, all of that, to show their devotion. Self-mutilation is way up on the list of a troublesome sign for somebody with elements of psychosis. Self-mutilation in these religious settings is sanctioned, condoned, celebrated, where people will particularly celebrate the folks who are most good at it. This is a whole domain of testing your body as a measure of your faith, and taking something which would be psychiatrically suspect in one setting, and here, anything but that.

Another version of this, and this is something that is now known historically as holy anorexia or anorexia mirabilis, that during the 13th, 14th, 15th century, it became very common for nuns, various nuns, to fast, to fast and fast and fast, sometimes to the point of death, to prove their love of God, to prove that they really could subsist without food, to prove. And you see, it's the exact same thing. One particular case, this one woman who became a nun, was brought up in a very harsh household, came up with a lot of fears, a lot of anxiety. She became a nun. And early on in it, she decided that she was sinful. She was always sinful because she was a glutton. All she thought about was food and sex. And she had to purge herself of that. And she fasted. She would insist she would eat three pieces of lettuce, and everyone else would say, "Come on, eat your dinner." And she would say, "Oh my God, I'm so full. I'm such a pig. I just filled myself up on that." All sorts of ideation built around avoidance of sex. She vowed to never be in a room with a man alone again. She had all sorts of fantasies where nuns ritualistically married Jesus. She had this endless fantasy that after she died and would go to heaven, Jesus would come and put a ring on her finger, a ring made out of his foreskin. All sorts of sort of imagery that she had about nursing from Jesus's breast and such. She went through all sorts of efforts to hide the fact that she would make herself throw up after the few meals that she had. She would stick a stick down her throat, all of that. And over and over saying, "I am sinful because I am gluttonous. All I think about

"is carnal stuff, and I need to purge this from me." And purging by limiting what goes in, and purging by triggering what would come out. And if this was your freshman roommate, we have an immediate term for it in the context of Western medicine. And this, instead, was celebrated, was acclaimed.

One of the best documented cases of this was Catherine of Siena, 14th century, Saint Catherine, canonized for starving herself to death at age 33. And soon before that, get a load of this, just in terms of disturbing imagery and such, she had transitioned to. The only thing she ate and the only thing she drank was, wait for it, the scabs of lepers and pus from their sores. She subsisted on that for the final month of her life and claimed that this was the most delicious nectar she had ever eaten. She starved to death eating leper scabs and their pus and all of that. And, you know, you think about it for the poor lepers. I mean, they have this horrible disease, and now on top of it, this lady is like trying to get their scabs off them and stuff, and that's an additional hassle. Holy anorexia. And again, she is a saint. She was admired. She was respected for her devotion. And she was not alone. This was a common phenomenon. Okay.

Then there's the whole question of making sense of religion as this conflict between cognition and emotion. And a wonderful quote from the evolutionary biologist Jerry Coyne: "In science, faith is a vice. In religion, faith is a virtue." And what you see is there's this constant battle between the two. In different religious traditions, there's the notion of faith for its own sake. Faith is belief in what cannot be proven and what cannot be disproven. A great example of that in both Luke and Matthew in the New Testament: Satan shows up and he's like hassling Jesus and dissing him and like all of that. And he says, "Okay, here's the deal. You know, you're Son of God. I get, I get. Okay. So, if you're really a Son of God, why don't you go up to the roof of the temple in Jerusalem and there will be a big crowd there and jump off. Jump off because if you're really the Son of God, then God is going to catch you, and you'll have proven it." And Jesus said, "Not so fast, you trickster. There's no way I'm doing that." What's the good of believing in a God who you see has actually caught somebody falling off a building? It's all supposed to be invisible. It's all supposed to be based on faith. Religion loses all of its oomph if the things you're supposed to have faith in have been proven. Jesus himself emphasizing that there.

So, we have this constant dynamic between rationality and this drive, this faith-driven drive that we have to see causality, to see agency, to see explanation for things. One example. Now, we get people, and he gets some video, and there's this little triangle coming up this hill and this big square comes down and knocks it off, and then it does it again and it does it again. And when people wind up describing the scene, they always personify it. This jerky square was being terrible, and this triangle was pushing the triangle who's just trying to get, trying to get up the hill. Agenticity on the part of the triangle. Note that if you're doing this with infants, you'd have to put faces on them. By adults, you don't need that at all. We're doing it all on our own. We are seeing agency there.

What you find is a whole style of testing where you show somebody a pattern of random stuff: random dots, random lines, random gyrations of the stock market, all of that. And you are asking people, do they see patterns in there? Is there illusory patternicity on their part? Do they see patterns in what is random? And what you see is people who describe themselves as being more religious, on the average, are more likely to see illusory patterns. If you give somebody a religious prime, and we know what those are about here, unscramble these misspelled words here. Spot the misspelling in this paragraph and load it in with terms with religious primes versus secular ones. It's the control group. Load it in. And afterward, people see more illusory patterns in things like this. All sorts of studies have been shown. You look at people's intellectual styles. Are they analytical? Are they intuitive in how they do stuff? And there's all sorts of batteries that test this. And people who describe themselves as being seriously religious, on the average, are more intuitive than analytical than you would expect by chance. If you prime somebody to think analytically, I love this one. In this one, there's flashing of pictures, including a picture of The Thinker. Who was that? Was that Rodin? Somebody did who I should know about. But The Thinker who's sitting there, I prime somebody with that, and afterward they will say both that they are more analytical, they're more respectable. Then they respect more analytical processes, and they rate themselves less religious than if you didn't prime them with that. Or all sorts of words. Cogitate, reflect, consider, all those sorts of primes. And you make people say that they are less religious and more analytical. You stress someone, you make them learned helpless, and they are more likely to perceive patterns in random data. We look for agency. We look for explanation. And we especially look for it in times of trouble and times of stress and times of duress, and that's where it becomes its most faithful.

Now there's a great equivalent of this in the behaviorist literature. And this is something Skinner first showed many, many years ago. You take a pigeon, and the pigeon is really hungry, and you suddenly drop a little pellet of food into its cage. And what does the pigeon think? It thinks, "Whoa, what did I just do to get that piece of food to come down there?" The pigeon perceives agency that is not there. And a little while later, you deliver it randomly another piece of food. And the pigeon says, "Oh my God, I was standing the same exact way." And by the third or fourth time, the pigeon is ritualistically standing this way. The, the, uh, the pigeon is ritual-like dabbing or standing on one leg or who knows what. And you condition this pigeon into believing that it has agency when it does not. That there is a relationship between what it is doing and what is in reality the random delivering of food. And Skinner called this superstitious conditioning. And that's exactly what it is. When you are a pigeon and you are hungry enough, you see patterns that are not there. You see causality, agency on your part, and you will condition that pigeon to do the most outlandish things that it just happened to be doing when the food arrived. And what you see is, in lab rats, if you damage the hippocampus, you lower the threshold for superstitious conditioning. It's easier to condition them that way. So we have this pull towards seeing agency, this pull towards seeing explanations. And of course, religion is great for that. And of course, deities are particularly great in terms of us, once again to phrase it as before, knowing what the instructions are for their care and feeding, knowing what pleases them, what displeases them.

And there's been a really interesting evolution with this. Earlier, back when predominant religions had gods that were recognizable, gods that were in human's image, gods that had gargantuan, godly appetites, but nonetheless appetites that were the familiar ones. And there's all those Greek gods wanting the, wanting the biggest sheep slaughtered for them, or wanted more nymphs than everybody else. And they seemed so human, so understandable. They were human with godly-sized appetites. They were understandable. And in a book called The Gift of the Jews, a very interesting one, um, what the person went over, I'm forgetting his name, an Irish historian, what he went over is, counter to what is often claimed, Judaism did not invent monotheism. That was almost certainly the Zoroastrians many, many centuries before. But what Jews seem to have invented back when is the unknowable God. A God who didn't have familiar appetites. A God who wasn't understandable in terms of what he or she wanted out of things. A God that was unknowable. A God that was pee-in-your-pants terrifying because you could not know anything about them. The invention of a hidden God, an unknowable God, and as we'll see in a bit, a judgmental God. That was a huge cognitive leap in religiosity. And you then see this is an open field of things you attribute to this otherwise unknowable God. What you believe that God is about, rather than being told stories that this is a God who really likes grapes, and that's the one who really likes hunting. And they said this one is unknowable, and you fill in the empty blank there with your own projective needs.

Great example of this: studies that have been done of religious belief in people on the autism spectrum. And they're religious at about the same rate as neurotypical individuals are. But what you see is different patterns of what is God? What is God about? And for many people, God is about judgment, or God is about love, or God is about whatever like standard tropes there are with that. And what you see with individuals who are pretty far into the spectrum, you see, what does God do? God is in charge of magnetism and gravity. God makes sure electrons don't spin out of their orbitals. This completely inanimate, detached version of what God is supposed to be like.

Really interesting recent paper looking at war vets, and of course they are like God's gift to neurology in terms of head injuries. And this was looking at populations of people with different parts of the frontal cortex damaged by a bullet or a shard or who knows what. And what they showed there was, if you have damage specific to the dorsolateral prefrontal cortex, you have people reporting a higher rate of mystical experiences. You have a higher rate of rational cognition tossed out in favor of intuition and metamagical stuff. So this constant trying to balance. Now, amid all of this, religion is a sanctuary for individuals who are troubled. Religion is a place where you test your body's devotion. Religion as this perpetual sort of conflict or balancing between cognitive aspects and intuitive belief aspects.

There's also a whole ornate world of religiosity built into philosophy and philosophizing about religion. And where the most interesting stuff has been done with this in the realm of our interests is something called temporal lobe personality. This was first described by Norman Geschwind, Harvard neurologist, one of the most influential neurologists of the last century. One always has to use words like "giant of neurology." Geschwind was amazing. And Geschwind noticed somewhere along the way that there was an interesting personality profile, not everyone, but at higher than chance levels, among people with a certain type of temporal lobe epilepsy. And he wound up calling this temporal lobe personality. What were its features? Person loses their sense of humor. Person tends to perseverate, repeat highly, highly habitual stuff. They eat the same meal every night for weeks on end. They have five copies of the same T-shirt. All of that hand-in-hand with that, they become neophobic. They are afraid of novel things. They develop, wonderful term, a "viscous," a "sticky" personality. They just get a couple of friends and stick close to them and have them stick close to you. And so you look at this and you say, "Well, okay, loss of a sense of humor. New stuff is kind of scary. You want to keep your real friends very close to you. Uh, maybe that's got nothing to do with some like interesting neurological thing. Maybe it's because you have a crappy, awful disease." What's the control group? People with equally severe types of epilepsy where the seizure originates in a different part of the brain. This is specific to temporal lobe epilepsy, where the seizures begin in the temporal lobe.

Two additional features that you see that Geschwind first described: hypergraphia, and obsessive writing. This is somebody who comes in and you're their new neurologist, and they say, "Oh, hi. It's great to meet you. I think really that it's important for doctors to see you as a whole person. So, I just prepared this little document telling you about my views about the world." A 70-page manuscript. And then the next week they come in with a 30-page addendum. And what are they very often being hypergraphic about? Religious philosophy, obsessed with it. So this is the profile. This is the temporal lobe profile. And there's already been one great novel called Lying Awake about a nun who turns out to develop this. And of course, it turns out she has a tumor there and has to decide whether her religious ecstasy coming out of all of this is a disease or a blessing, and what she should do about it. But this was this profile first described by Geschwind. And it gave rise to this wonderful anecdote where Geschwind, you know, neurologist, he would go around with a neurology in residence. And then they would do rounds on their own in the morning. And like one day they come in, and the chief resident was sort of reporting on this one kid in one of the rooms, this, this kid who has temporal lobe epilepsy, and sort of his med status and all that sort of thing. And then at the end, he kind of wanted to poke Geschwind, no doubt, like a young, young stud on his way up dominance display or whatever. He said, "Oh yeah, by the way, I talked with the kid some, and he doesn't fit your profile, that temporal lobe personality." And like Geschwind said, "Yeah, how do you know?" He said, "I asked him if he was religious, and he said he wasn't." Geschwind says, "Idiot, out of my way!" and goes storming down the hall with the chief resident, all the other residents running behind him. And they come into the room, and Geschwind gets in there and does like a neurology workup on the kid and then says to the kid, "Oh, by the way, are you religious?" And the kid says, "No, I'm not." And then Geschwind asks the key question. He says, "Oh, why not?" And this like 12-year-old launches into an hour-long lecture about the inconsistencies of Christ's Sermon on the Mount and Bertrand Russell's critique of Christianity and all. And at some point, Geschwind leaves the room and just left the chief, the, the, uh, senior resident there stuck with this kid and saying, "Take notes about what he's saying." It's not that you are religious. You are obsessed with the philosophy, the very cerebral aspects of why you should or shouldn't be religious.

More aspects of this hypergraphia, there's been at least one paper and like make of this what you will, but by one neurologist doing sort of like, I don't know, after the fact, like retrospective neurology diagnosis, arguing that Saint Paul had temporal lobe epilepsy. He was described as, well, there's no evidence of him coming up with a lot of jokes. Um, he was hypergraphic like crazy. He helped write the Bible and all of that. He was known to have epileptic seizures, and of the descriptions of it sounded like temporal lobe grand mal seizures. And the guy was certainly into religiosity stuff. Who knows? But nonetheless, another version. Think about this. You struggle with these issues for years on end, perhaps trying to decide what religion means to you and the role of your deity or deities in your life and all of that. And instead, have some screwed up potassium channels so that once every few months they start firing like crazy in this part of the brain. And you arrive at the same place with the same endpoint there through a very different mechanistic pathway.

Okay, so this takes us now, coming out the other end of this stretch. What do genes have to do with religious belief? And all sorts of people have speculated about it. And the gene for this and the gene for devoutness and the gene for meekness and the gene for inheriting the earth and the gene for... And this was very popular, I don't know, '80s or so. And, well, I'm not going to say gibberish, but not far from completely, completely incompatible with anything that was known about genetics at the time. Religiosity is almost certainly genetic insofar as you got a genome that, among other things, specifies 80 billion neurons. And we get some emerging complexity stuff, and out pops structures like religiosity, along with aesthetics and philosophy and economic views and everything else there. Yeah, it's an emergent feature of us, but there is zero evidence for a gene, a handful of genes, for any feature of religiosity. And to see how paper-thin whatever genetic component there is to religious belief, all you have to do is say one word: Scandinavians. Back when, sort of mid-19th century, Scandinavian countries were highly religiously observant, Lutheran, and as devout as anybody else in Europe. And somewhere around that time, the Scandinavian socialist model of states taking care of its people evolved. And with each passing decade, fewer and fewer people in Scandinavia say that they are religious, that they have a god, that they believe in. And it is now probably the lowest rate of any European population. You don't breed out your genes for religiosity over the course of a century or so. Tells you a lot about the social context for where religiosity is coming from.

Okay, ecology. You already know about this. Takes us back to that song and dance about desert dwellers versus rainforest dwellers. And desert dwellers are monotheistic and come up with punishing afterlives and gods who pay attention to what you're doing. And rainforest polytheistics and all of that, and how you make a living. Are you a pastoralist? Are you a farmer? Are you a hunter? Very different sorts of religions that are made. One extremely interesting idea, and then shown in the data, come from the psychologist Ara Norenzayan, who's up at the University of British Columbia and does fascinating stuff. What he has shown is studying sort of the history of religious belief and what sort of deities different populations, different cultures make. And what he showed is that, judging from contemporary hunter-gatherers, 99% of human history was spent inventing gods who had no interest whatsoever in what humans were up to. Were completely disinterested. Were not monitoring you. Were not making judgments about you, anything like that. Hunter-gatherer gods are indifferent to humans. And what he showed historically is it's at a certain point of societal complexity developing that you get the invention of what he called "big gods." Big gods who monitor us, who keep track of what we're doing, who could see us when nobody else can, who could read our thoughts, all of that. Big gods who can judge us and who mete out reward and punishment. It was around there that there was the invention of hell. What was the point of societal development when that began to emerge? At the point that people were living in high-density populations, high enough that you could interact anonymously with people, that people you would encounter on a daily basis, you wouldn't know who they are. They wouldn't know you. You might never see them again. The possibility of anonymity. And what he shows is it's right around that point, at a certain size and population density, that suddenly people start inventing these big gods, these moralizing gods that are paying attention because if nobody could see what you're doing or you're anonymous and all of that, time to have somebody who can always see what you're doing.

Okay, so that is one level of this. You also see what types of cultures produce what sorts of religions. What you see is across European history, the more poverty in a culture, the more violence from on high, usually top-down violence from the feudal lords, the more disease, infectious disease load, all of that, the higher the levels of religiosity. And this is something that continues to be a pattern throughout the world.

Okay, evolution. How about the evolution of religiosity? Let's get the notion that there's a gene or even a handful of genes relevant at some sort of emergent property. But what about the evolution of religiosity? And we can view this on two levels. One, the individual. What does religious belief have to do with how many copies of your genes you leave? And what is a very clear finding throughout Western religions is religious belief is good for your health. It's good for your lifespan. It's good in all sorts of ways. People have known this for a long time, but it comes with confounds. First confound: people who are highly religious tend not to have substance abuse problems. So that doesn't wind up being a factor. People who are highly religious, most importantly, have a community, a community of social support. And we know from psychological stressors that that's incredibly important to have. And your control group has to be groups of humanist atheists who also form social communities that support each other. So you got to control for that. But once you control for that stuff, religiosity is a protective thing for health. And it makes perfect sense. Back from our psychological stressors, once you have that, you have an explanation for the things that are inexplicable, that are unknowable. It involves, with any luck, a deity who is loving. With any luck, a deity who is especially loving for people like you, with the best luck is especially loving for you above all else and all. And it is an enormously protective thing. And what you see is religiosity, independent of the community effects that you get and independent of lifestyle risk factors and protective factors, is good for your health, which is in some ways infuriating to me.

Okay, how about the evolution of religiosity on a group level? Finishing up here with group selection, because a religious group is like our textbook example of something that should be brought about at a group selection level that is glued together with cultural green beards. The fact that you could go on the other side of the planet and see somebody with just one simple symbol that they are communicating a green beard trait, and you know that this is a co-religionist, and already you are biased towards cooperative behavior with them. What does this do? David Sloan Wilson, from oh so many weeks ago. David Sloan Wilson, who championed the notion of multi-level selection for years and years and years while everybody laughed at him, and the notion that multi-level selection included cases of group selection that were unique to the human situation, and everybody laughed at him. He's done a wonderful analysis in a book of his called Darwin's Cathedral: the emergence of all sorts of separate Christian religions in Swiss cantons, 18th century, I don't know, I don't quite remember. And this whole analysis of what it is about Calvinism that they're the one that turned out to dominate the whole place and drove all these other ones into extinction. What were their group properties? What were they doing? So that even though A was subordinated to B, a group of A's, Calvinists, would subordinate a group of B's. Totally interesting book looking at the evolution and the extinction of religions in relatively recent history as a means of seeing group selection playing out.

Okay, so this total hodgepodge survey here, what has this gotten us to? Once again, what I want to emphasize more than anything is, nowhere in there am I saying anything nutty like, "Ooh, you got to be crazy to be religious," or, "Ooh, most people who are religious, they're psychiatrically suspect." Not in the slightest. What I'm also saying is that it's just as interesting stuff going on with atheism and loss of faith and agnosticism. It's just harder to study because there's fewer people like that, and you don't have centuries worth of ritualistic traditions to look at their evolution. Things of it is equally applicable. The biology of holding on to faith, the biology of losing faith are equally interesting and equally valid. I guess the final point is something that again harks back to this notion before of lots of us, me for example, spent certain formative years of their lives wrestling with the place of religion in their life, and wrestling with what they thought of why we are here and what's our purpose and is there an afterlife and all of that. And I think for lots of us, wherever we wind up at the end, it could be a huge struggle. It could be a lot of work. What do we make of the fact that instead here, biologically, this type of hiccup or that type of hiccup or this type of any of the things we know about by now biologically, and you arrive at the same place, and it feels just as valid. I find this to be fascinating.