The Jordan B. Peterson Podcast - 184. Death, Disease, and Politics | Dr. Randy Thornhill

Episode Date: July 26, 2021

This episode was recorded on May 10th 2021.Jordan Peterson’s guest today is distinguished Professor Emeritus at the University of New Mexico, American entomologist and evolutionary biologist, Dr. Randy Thornhill.Dr. Thornhill’s research shines an enticing light on scientific areas that most people have never been exposed to. We come to understand and appreciate the importance of evolutionary biology in shaping our opinions, attitudes, and in many cases the decisions we make throughout our lives. Dr. Thornhill has authored and co-authored around 250 scientific publications, and a majority of his work has been cited in scientific literature over 35,000 times.Dr. Thornhill shares his findings on attractiveness including cryptic female choice, symmetry, carotenoid pigments, and the characteristics of attractiveness. They also cover Dr. Thornhill’s parasite-stress theory, the critical role that infectious disease plays in humanity, IQ, sex, religion, and conservatism.For information on Dr. Randy Thornhill’s publications, visit: https://www.amazon.com/Books-Randy-Thornhill/s?rh=n%3A283155%2Cp_27%3ARandy+Thornhill

Welcome to the Jordan B. Peterson podcast. I'm Michaela Peterson. This is season four episode 38. This episode was recorded on May 10th, 2021. In this episode, my dad's joined by Dr. Randy Thornhill. Dr. Thornhill is an American entomologist and evolutionary biologist. He's authored and co-authored about 250 scientific publications and his work has been cited over 35,000 times. Dad and Dr. Thornhill discuss Dr. Thornhill's findings on attractiveness, as well as other subjects, like cryptic female choice, symmetry, caratenoid pigments, and the characteristics of attractiveness.

I hope you enjoy this episode and enjoy your week. [♪ OUTRO MUSIC PLAYING [♪ Hello, everybody. I'm pleased to have with me today one of the world's great biologists, Dr. Randy Thornhill. He's an evolutionary biologist and distinguished professor of biology, a meritus at the University of New Mexico, with a primary interest in animal behavior and psychology, as well as human behavior and psychology. Dr. Thornhill and his colleagues have authored or co-authored about 250 scientific publications, including four research monographs or books. His publications have been cited

in the scientific literature more than 35,000 times. A citation score is the number of times a reference to a given piece of research is cited by another researcher or in another publication by the same author. A scientific citation count in the tens of thousands clearly indicates that a researcher occupies a position in the upper echelons of scientific influence. Dr. Thornhill is a founder of the research disciplines of behavioral ecology, evolutionary psychology, evolutionary aesthetics. That's the study of the experience of beauty from an evolutionary perspective. Evolution and human behavior, the modern study of adaptation and the study of

sexual coercion. Dr. Thornehill, thank you very much for agreeing to talk to me today. Thank you for inviting me. Pleasure to be here. Thank you. Thank you. So I've come across your research a number of times in my career struck by its originality and its impact. I'd like to ask you first about something I probably ran into. Maybe it's 20 years ago. Maybe it's 15 something like that.

You did some work on the perception of attractiveness, bilateral symmetry, averageness, and sexual selection. Can you outline what you found and why? Yes, I did work some years ago now in human attractiveness, and that turned out to be very productive about attractiveness in general in animals. And one of the key traits that animals look at in judging physical attractiveness effectiveness of partners of mates is bilateral symmetry. And a colleague and I in the early 90s came up with a way to measure facial symmetry in humans. It had been worked on before, but the measurements that they used were didn't work.

So we came up with a method that did work, measuring bilateral symmetry in the face. So that is the symmetry of the two sides of the face. Why is that important? And why is it a marker for attractiveness? It turns out that, that bilateral symmetry is a measure of developmental health. And so the, the organism, uh, when it starts developing, it's designed by evolution, by selection, to achieve a bilaterally symmetric form. You can think of that, this is the case,

I wanna say organisms, I mean all forward moving organisms. All forward moving organisms have adaptations, developmental adaptations to achieve a bilaterally symmetric body because first of all, that reduces drag. So if you're moving forward and you're bilaterally symmetric, you don't have any drag in your movement. You can think about a person with a leg a bit shorter than the other.

And there's drag in the forward movement. Now more of that asymmetry, the more drag. So you lose efficiency in movement. That's fundamental to what bilateral symmetry is about. But next, bilateral symmetry is very hard. Perfect bilateral symmetry is very hard, perfect bilateral symmetry is a very hard to achieve by development. So it's a marker of quality of the individual pertaining to its developmental health. We see in many things that human beings design to move forward bilateral

symmetry. Cars or automobiles are bilaterally symmetrical airplanes are bilaterally symmetrical so we like a world to be that way. Yeah, we like to be that way actually it turns out and well, we're associating it with the more principle. If you had if you had one side of the car asymmetric compared to the other side of the car, then it'd be more direct, you know, it's not an official, you'd use more gas, think about it that way, in driving down a road with an asymmetric car. But so this, this is one component of physical attractiveness, bilateral symmetry. And we looked first, we developed this way to measure facial symmetry. That became a very hot research topic. We did the first, and then others followed very quickly. And lots and lots of research have been done now. But there's symmetry of movement that's important in how fluid ones movement is and how attractive, therefore, one's movement is,

you're not dragging your foot or whatever. And all that is really a component of the importance of health in physical attractiveness. So physical attractiveness fundamentally is a health certification. That's how we judge people's attractiveness. We don't think about it consciously. It's an unconscious calculation of the traits important in health and developmental health as bilateral symmetry is one of these.

So you measure the symmetry of the two sides of the face and we showed in our first study of this way back now that that measurement relates to how attractive faces are perceived, try to face in the same sex or opposite sex. And then that research went on to look at kids looking at faces and different ethnic groups looking at faces. It works like a charm. Why do you do it? The lots and lots of research. And so does it mean that if you show people symmetrical or asymmetrical faces

that they obviously have a preference for the symmetrical faces, will they look longer at the symmetrical faces? Will infants look longer at symmetrical faces? Yes, they do. Yeah, that's the way the infant beauty research is done. You just look at whether the baby, and they got it down now to almost newborns, you know,

looking at faces and judging these faces basically on the basis of interest, how long they look at the face versus getting distracted to something else. And symmetry is one part of the beauty, whether you're talking about babies or kids or old people or young people or whatever, facial symmetry is very important. It's not the only beauty marker in the face we look at. We can talk about that in a moment too because that gets us into some

other research we've done, but symmetry is a very important one. Now that research went on to look at how symmetry plays out in the everyday lives of people. And we did the initial studies on that, but again, that research boomed and lots of people have done it and still it's an active part of research. But the first thing we did, not just attractiveness, we did a bunch of bad in relation to symmetry.

But we looked at sex lives of people, romantically paired people, studies of couples, and looked at reports by men and women of sex partner looked at reports by men and women of sex partner numbers they've had in their lifetime that was one component of because that's a that's a measure in men in particular of what biologists call mating success so a number of number of sexual partners one has and And that research showed that for me, the more symmetric demand, the more sex partners he had. And a technical tale there, after we, you know, initially started with facial symmetry, but then we moved to the body of people. We came up with a metric for body symmetry measuring 11 traits on both sides of

the body. These traits are ear length and ear width and then we measure elbow. There's an elbow anatomy there that we measure some bones, wrists, fingers, all those men measure, of course, on both sides, measure foot width, ankle width, trace like that. Now we put that together in a composite as a measure of body bilateral symmetry. That correlates highly with facial symmetry because this symmetry is a developmental health measure

throughout the body. And that correlates with mating success of man. More symmetric man are physically more attractive and they have more sex partners. We also got into looking at men's infidelities in their relationships and found that more symmetric men engage in more meetings outside the Parapon as well.

So that's part of their mating success. We did the first study of a kind of modern study we would call it of female orgasm in in relay in in in in in in in in in in in in in in in in

in in in in in in in in in in in in in in in in in in in in in in in in in

in in in in in in in in in in in in in in in in in in in in in in in in in in in in in in in in in in in in in in in in in in in in in in in in in in in in in in in in in in in in in in in in in in in in in in in in in in in in in in in in in in in in in in in in in in in in in in in in in in� in in in in in in in in in And we found that the men's reports and the women's reports, a frequency of copulatory orgasm by the women, were very how to correlate it. So, men are paying attention to this from all of them.

And that's whether the female is sexually aroused to the zenith level of orgasm, of course. And more symmetric men were firing more copulatory orgasms too. That was a very classic study in human psychology. So I have a specific question about that. I've always wanted to ask a biologist interest in sexual behavior, but I know that there's

been a lot of discussion about the hypothetical evolutionary purpose of female orgasm. And I was wondering if female orgasm is disproportionately likely to trigger male orgasm. Because it could be an adaptation that's used to illicit pregnancy, essentially. Yeah, I don't think it is. There's no evidence that females,

that orgasm very infrequently have fewer babies and actually women who don't ever orgasm very infrequently, have fewer babies, and actually women who don't ever orgasm can be quite fertile. So I don't think it's fundamentally that. I think what it is is it's part of female mate choice and more basically, sour choice of the female. Let me explain. So when a female has an orgasm,

she has uterine contraction, of course. And that pull, it works like a suction. It pulls the content of the vagina up to the cervix. So it puts the content of the vagina in a good place. And if that content includes the male's ejaculate, and she's pulling the males ejaculate up to the cervix, where it's easier for him to get, either for the ejaculate to get into the right place

to conceive. So if she, imagine a female who has two mating partners, she orgasms with one, pulling his ejaculate up to the cervix. And she skips orgasm with the other partner. So she in effect is mated with both men. So that is, you know, same mating success of the two men, if you just look at mating success.

But she's doing something more subtle that is differentially affecting the fertilizing capacity of the ejaculate of the two men. The ejaculate she pulls up has more potential for fertilization. And that's a component of cryptic female choice first in insects. And then it applied to female orgasm too in humans. As a cryptic female choice is just the kind of female choice that is invisible if you're only measuring mating success. So in the example we talked about, the two guys mating with this female had the same mating success, they both made it with.

But one was preferred over the other by the female's orgasmic capacity with him that pulled his ejection up. And so females by showing this differential orgasm pattern that I described with symmetry are favoring symmetric partners over other men. Hypothetically healthier partners and with an advantage. That's right, higher genetic quality. And then that's that's an issue behind all this discussion so far is that female organisms are after high genetic quality partners when that when you know to be fathers of their offspring. So it's a sire choice, more the apryptic female choice, more of a sire choice than just a

mate choice. And Darwinian, Darwin chose Darwin discovered female choice and did a lot with it, for sure. And biologists had viewed female choice in a Darwinian framework up until very recently until apryptic female came along, but female is a far more sophisticated than just choosing one male over another as a mate. They do these subtle things and involved in cryptic choice to prefer some sperm of some mates over the sperm of others. Whole sweet math, that's a big area. Well, what other elements are, what other elements make up cryptic choice? You just were guessing. What else? What else?

First discovery was in some insects called scorpion flies. And what the females do there is they adjust mating duration and enhance the amount of ejaculate that the male transfers. There's no orgasm in these insects, but the longer the male can mate, the bigger the more sperm he transfers to the female. So females are adjusting ejaculate duration on the base of body size and male. So and bigger males are more fit males and so forth, better growth and more resources

growing up, the higher quality males. The females are receiving more sperm from bigger males. That's one thing I did with these insects. Another was the female, after she mates with a male, makes a choice of whether it's a lay eggs or not. If she chooses to lay eggs, then she will fertilize, we know, mother research I've done, she will fertilize those eggs with the last male sperm she made it with. So if she makes the decision lay eggs, she's going to use that my last male sperm sheet and large

males again are preferred in that component of cryptic female choice. So cryptically, if you need female scorpion finis, her preferring large-bodied males, by both receiving more sperm from them and making decisions to lay eggs with them and not other males. So those kind of subtle things that females do that aren't apparent if you're just measuring classical male mating success, you know.

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code JBP to save $5 off. And is symmetry in human beings? Is it associated with longevity? Is it associated with decreased probability of the world. And the community is associated with longevity, is it associated with decreased probability of disease in the

future, is it associated with higher general cognitive ability, like are there other factors that for cognitive ability, we did that research,

and that's now there have been thrift or repetitions of our initial research. We dated on 200 subjects, similar A, so university students, the site who will kind of study and measured that queue,

using a culture fair measure of IQ, culture fair procedure, and, culture fair procedure, and questionnaire measured that Q and then measured the symmetry in it for both sexes, the higher the symmetry of the individual, the higher the IQ. So do you remember the size of the relationship by any time? That one was about 0.3,

it's a moderate relationship, right? Q. There's measurement error in IQ, there's measurement error in measuring developmental stability as symmetry, too. So we measure 10, 11 traits. If we measure 50 traits, present we get a correlation of say 0.8 with IQ. You know what I mean?

There's all that measurement. And know what I mean? There's only measurement. And the IQ relationship would exist hypothetically because the healthier individual would be prone to a more favorable pattern of neurological development over the question of life. That's the idea, exactly. The, some colleagues went on to look at some brain features in relation to developmental stability of the outer body. So they did imaging, brain imaging studies

to look at certain brain parts. Some brain parts are bilaterally asymmetric by design. So one beer on one side and than corpus colosum, the tube connects the two hemispheres, that's just a size factor, which you can measure the size of that conference of the corpus colosum as they did. And the bigger the tube,

the higher the body symmetry of the person, bigger the corpus colosum, they measure a couple of other brain parts too, and showing that, showing that, so you can talk about a modal directionality for an asymmetric trait. So there's a there's a mode, the most common degree of asymmetry in an asymmetric trade. So like hand in this and so forth. Six is, you know, the average person or the model person, 60% right, 40% left hand use. You can measure deviation from that as another measure of developmental instability. And that was the kind of thing they did with the brain parts, these asymmetric brain parts. So that's that's deviation from averageness in a sense. In a sense, yeah. Now you also did work on

averageness and detractiveness. It's some stuff with the averageness, but we're really just to control it because you can do average facial features, you know, no size, eye size, lip size measurements of face. Right, and people have built composites of faces to produce average faces and had people rate them. Average, average-ness average faces is a more attractive than non-average. However, average is not the most attractive face. The most attractive faces deviate from average in predictable ways.

You want to talk about it? Sure, yes. So you're a average model's faces, unpredictable ways. You want to talk about it? Sure, yes. So you're an average models faces and they seem more attractive than average faces and maybe that contains. Yeah, well, yeah, but you can take a model and you can make, you know, make her a knock drop dead by the following computer manipulations. it by the following computer manipulations. What you do, if she's a female model, not a male model, if she's a female model, you do the estrogen modifications on her face through computer techniques.

So you reduce basically lower face size, chin size, jaw size, those kinds of things that are under estrogen control during puberty and adolescence. And for male face, you manipulate an opposite direction. So male faces are more attractive when testosterone is not estrogen-ost and female faces are more attractive when estrogen-ost. So the female model, facial models, get their job because they're highly estrogenized faces. Are they neautinous? The female attractive faces? Are they more neautinous?

Yeah, they're more neautinous in a sense of, so a woman who makes her living with her face, face model, her face is about the size, lower faces, about the same size as a 10-11-year-old girl. So, Neoughton, in essence. So, Neoughton is the tendency of an organism to evolve towards its childhood, morphology. Yeah. So, okay, so, Neoughtonist, Neoughtonist-averaged females are more attractive. Yeah. So, neoughtonous average females are more attractive. And so now, is that just out of curiosity,

do you think that the attractiveness of that neoughtney is a consequence of the ability of the more childlike face to elicit care from a male? Yeah, elicit care and interest and attractiveness. So basically, here's the way we think it works. So the neoughton we're talking about, we can talk about it just as the degree of estrogenization of the face. That's what we measure.

That is a marker of health in a different sense, hormonal health. So estrogen, estrogen is fundamentally the fertility and reproductive capability hormone of the female mammal, estrogen. So the more estrogenized she is, the greater her fertility and reproductive capacity is. So that's what we're responding to in the physical attractiveness of a female.

Is there an association between averaged neotenous faces and optimal waste to hip ratio? Yeah, well, yeah, the estrogenization affects not only the facial features, it affects bones and so forth. So, you know, petite people talk about petite women as attractive, she's so petite and so forth. What they're talking about is estrogenization of bones throughout the body, not just the face,

but, and that includes the, the waist hip ratio is really a marker of degree of estrogen ization of the female body, low waisted ratio. So a small waist relative to more expanded hips, smaller the waist relative to the hips is a marker of estrogenization of female body. And that again is a marker of female reproductive capacity through the estrogen effect. And that's optimal at about 0.68, is that really resourceful? Yeah, you're, you know, underwear models, female underwear models, they're down,

they could go as low as 0.66, 0.68, you know, be a model. So what other elements of attractive, okay, so a couple of things here. So the first thing that's really quite interesting is that your work points to, or this work, this entire line of work points to a profound biological basis for the experience of aesthetic attraction, at least in relationship to the perception of other people. And of course, the perception of ourselves. You're right. The tremendous amount of that's grounded in instinct, apparently. Yeah. And it's an instinct that's manifest so early that you see the preference for attractive faces, the same measured by averageness in newborns.

Do you see the same preference for test-auster-ronized males and estrogenized females among newborns? Or is anyone looked at that? Yeah, yeah. Kids and down to very recently born kids have been looked at in terms of their judgment of men's faces too. And that's they're looking at testosterone features there, you know, you call it masculinity, you would mean to call them testosterone technically. And these features that grow under the

influence of testosterone during puberty and adolescence in the male. And in the female, they're growing under the influence of estrogen. Basically, estrogen just capped in the growth of those facial bones and the other bones too. And to, but testosterone, along with growth hormone promotes the growth of the same bones in the face and body of the man. And so babies are judging men's faces the same as you and I are a personal street boy. That's what the research shows. Yeah.

This was promoted. There's a book called The Beauty Myth, for example, that purports to claim that conceptions of female beauty are what would you say? Arbitrary social constructions. What do you think about that idea? How powerful is the biological impulse towards aesthetic experience?

It's the reality. The biological research I'm referring to has been so abundant since the really starting in the 90s that really kicked it off was stuff we did initially on symmetry. And then researchers got into the hormone markers, beauty markers involving hormonal health. And the most recent latest been,

there's been another drive to look at some pigment issues in terms of a beauty marker, a carotenoid pigment in particular. But it's all health. It's all health. And the beauty myth, Gail, I forgot her name. Now I'm inclined. Yeah, right. That was just just blinding ideology, eranting, had nothing to do with reality. And then there was enough known about sexual selection processes and animals to cast that idea and end out. But since then, it's just, it just great. Well, because you see this

preferences that you've been describing, you see analogs of those and variants of them across the entire animal kingdom. And you see the preference in newborns. So it's pretty hard to construct a social constructionist view of the aesthetic experience of attractiveness, given all that information. Right. Well, the first study on symmetry that I did, the role of symmetry in sexual selection, competition for mates and mate choice, that was done on insects. At the same time, unknown to me, a Danish biologist was studying barn swalls

and tail symmetry and barn swalls. And we co-discovered this role of symmetry in sexual selection independently. He's working on barn swallows in Europe. I was working on scorpion flies. And then I got into humans too. But yeah, and then following that biologists working on all kinds of critters, you know, looked at the symmetry paradigm in their in their favorite study animal and I think by 1997, 1998, 75 species of animals that have been shown in which symmetry plays an important role in the sexual selection system of the animals. Yeah. So it's very robust, at least.

So fundamentally, we find we use markers of attractiveness for across both sexes to indicate general health and more than health is it also an indicator of general competence, it's associated with general cognitive ability. What about personality markers? Has anybody looked at that? Like are people who are symmetrical are they less likely to be high and negative emotion,

for example, or? We look for it. The guy did most of the research on sex and symmetry in humans. He's a psychologist and works in a psychology department. I'm a psychologist too, but I don't work in a psychology department. But and we got right into looking at personality, thinking of Mike Corley with personality and nothing. And others have tried it too. So it's not a symmetry,

it's not a part of the personality paradigm. Yeah. Yeah, well, it's not obvious that there's an optimal personality. Perhaps that's part of it, is that there seems to be niches for personality that are useful for all sorts of different personalities. I mean, it looks all things considered like higher general cognitive ability is better

across multiple domains, but it's not so obvious with personality, so maybe that's part of the reason that's not so robust. I was wondering more with sensitivity to negative emotion because I thought maybe that less healthy people would be higher in trait neuroticism and that might show up with symmetry, but you haven't found anything like that.

No, we didn't find anything that was condensing there. I see what you're saying, though, that would be a reasonable prediction to get into. And in the personality domain, we can get into that when we start talking about the parasite stress. Yeah, so let's move into the parasite stress theory now. Apart we do, let me just summarize the beauty thing in two minutes. Great. So the current knowledge, the reality about our judgments of physical attractiveness,

empirically based knowledge, the uncount of knowledge, there's real knowledge, but empirically based knowledge of how we judge physical attractiveness in terms of facial and bodily attractiveness. Is we use health markers? And those health markers are developmental stability, that's symmetry, hormonal health, that's another one. And senescence is a third. So as we age, we lose attractiveness, of course, and we lose function at two. And so we pay attention to age and senescence effects when we judge attractiveness, of course. So symmetry or mono-effects and senescence, then the final one,

the most recent marker of fiscal attractiveness that has been discovered is the carotenoid pigment thing. And it's pretty wild. So, carotenoids, you can't make. We don't animals don't make carotenoids. You get them from diet. We eat carotenoid-based foods or our animals that have eaten carotenoid-based foods. So you get all of our croitnoyes.

And the croitnoyes are very important in metabolism. So fundamental to metabolism. You gotta have a lot of croitnoyes. If you've got a lot of croitnoyes, then you've got excess croitnoyes. You put those croitnoyes in your skin and then the yellow colors in skin and the yellow tints in skin and then have anything to do with what your racial background is or whatever.

There's there's yellowness in the skin of African Americans, Caucasians, or whatever, Asians, there's yellow pigment there. The degree of yellow is important in attractiveness. We assess it when we look at when we look at faces, the more yellow, the more carotenoid the person has, the more excess the carotinoid, the person has, can put it in their skin. And what crotinoid says is that you have to have a healthy gut to absorb crotinoid. It's fat soluble and you can't absorb fat if you're gut sick. So the yellowness in skin is a marker, another marker of health that we use. And that's only been discovered in the last 15 years or so. From what foods are carotenoids derived? Your fruits and vegetables for the, you know, their full of carotenoids, so you want to eat a lot of those. And you get 30. So is it also a marker of your ability to provision yourself?

Well, that too, which you can provision yourself with any of that. And you know, it doesn't show up in your skin. Right. So that's not a higher quality marker of provisioning. No, it's a sign of metabolic health. Right. Right. Yeah. If you're, you know, healthy body looking like that, that's a good indicator. But this is specifically related to your overall gut health and allow, you know.

So is it reasonable to say now that we know enough about the biology of attractiveness that we could build an optimally attractive form purely based on the scientific data pertaining to health markers. Yeah, that's what we look at ankle measurements and we and symmetry and waste dep ratio. I can take a female model, famous facial model and take that face, digitize that face into the computer like off the cover of Cosmopolitan or wherever, and I've done this. And I can make that make her even more attractive through reducing the increasing the estrogenization components of her face. I can make her more attractive.

So if I want to be particularly successful on Tinder, I'd put up a representation of my face, but I'd make it bilaterally symmetrical. So I could duplicate maybe the left side of my face. I'd make my skin yellower. Yeah, make your skin a little yellower. Yeah, yeah, you can do it. I mean, the last most recent research on the yellowness thing, the thing, chronic thing, is people would do, you do experiments where they put people on different diets and they measure their, you know, take their facial picture before the experiment and six weeks after.

In six weeks, you can improve your facial attractiveness by carotenoid, including more carotenoid in your diet. So it could be pretty quick. And students love this when we talk about in class, of course, and tell them how to get prettier and hurry. Yeah. All right, so let's move to next major topic. I came across your work on parasite stress theory a few years ago. I started to get interest. There was a burgeoning literature on the role of disgust in political idiot. And I ran across your parasite stress theory. And so, and you were looking to begin with that, the relationship

between parasite stress and values. And so, maybe we could delve first of all into, well, what parasite stress is and how you would study that in relationship to value and why you would ever think to do that because it's by no means obvious. Okay. So the parasite stress, what we call a parasite stress theory of values. We also call it the parasite stress theory of sociality

is a scientific theory about how people get their values. So the causes of people's values and the theory is a theory about both proximate causation and ultimate causation. So in biology there are two general categories of causation, proximate, ultimate. Proximate causation has to do with causes of something that occur during the lifetime of the animal, the adventuring the lifetime that cause whatever effect you're looking at. That's proximate causes. Ultimate causation has to do with causes in the deep-time past,

evolutionary past, so ultimate equal evolutionary approximate equal causes during the lifetime of the individual. And this theory of parasite stress theory of values is both approximate, ultimate theory about how we get our causes. So let's start with the approximate level of causation of our values and what I mean by values. So that's kind of a big topic.

If you look at the history of research on values, it is very large, but we could think we could and almost unbound it. What psychologists have called values. So, value would be something like rank-order preference, if we're going to define value itself, right? Because we have to choose between things. And we choose the values. That's value. Oh, yeah. We were talking about the value people place on looking at one face versus another. That's a value.

That's a preference. Right. And they'll donate more attentional resources to high value faces because attention is a marker of value. Right. We can talk about what psychologists have called values and the study of values. And that's a big, big area of research, values research. And the history of it and all is really, really cool.

But anyway, we can, we can sort of boundless discussion of values in what political scientists refer to as values. And what they refer to as values is they political dimension of highly conservative to highly liberal. So it's a continuum of values. And you can measure a person's values. They work hard to come up with ways to measure a person's values. They've worked hard to come up with ways

to measure a person's values. You measure a person's values. You can put that person on that continuum somewhere. Everybody can be put on that continuum from psychometric procedure, questionnaires. So the political scientists have done values that way. Cross-cultural scientists have done values that way. Cross-cultural psychologists have done values in terms of collectivism and individualism, that dimension,

with collectivism, high collectivism, being low individualism, high individualism, being low collectivism. It turns out if you look at these two dimensions, one from psychology, collectivism, individualism, one from political scientists, conservatism, liberalism, they correspond. So, high collectivism is conservatism. High liberalism is individualism. And so, you can think about

what I'm talking about in terms of core values by those two dimensions, the conservatism, liberalism, and collectivism, individualism. And basically, as I show, they are, as we show, that those measures, those dimensions are very, very similar, if not identical. But do you take them apart a little bit and talk about collectivism, conservatism, and liberalism, individualism? So everybody knows real hard. Will indeed. Yeah, excellent. Yeah, so you measure these, you measure these,

a person's collectivism, said differently, you measure his or her individualism. And you're what you're measuring. So let's start first with conservatism. So a conservative person has sub, there's subcomponents of this value system. So the person has beliefs importantly in traditional things, traditional things things and parochial things,

local. Also the person is relatively xenophobic. It's conservative people, relatively xenophobic. And xenophobia is fear, dislike, avoidance of stuff on the outside, foreigners, people, new ideas. So xenophobia has a neophobia component. Neophobia means phobia about the new. So you like traditional stuff. You don't like new, you don't like foreign. That's xenophobia component. So conservatives have So conservatives have the xenophobia, the traditionalism, parochialism. They also are high in ethnocentrism. Ethnocentrism is a preference for people like you. You're in group. You define your in group that starts with your, with your, with're in group, you define your in group that starts with your with your with your

nuclear family, but then extends an extended family and others with like values like you. So that's your ethnocentric component. And another component of conservatism is liking to just stay home. So, philipatric love of where you're born, you stay there your whole life and so forth under highly conservative, highly conservative culture, you don't move much. So, that's conservatism. And then the antipole of those values really characterizes individualism or liberalism.

So instead of xenophobic, you're xenophilic. You like people that are different from you. You're comfortable with other kinds of people, even if they have different values, even if they have a different color, even if they believe differently. You're more comfortable with those than you are if you're conservative. And ethnocentric, as our centristism is low under individualism and more nuclear family

oriented than extended family oriented. And your in-group is really composed of people with all kinds of different beliefs and maybe colors and so forth, backgrounds, as an individualistic or liberal. And you're more prone to moving around. You have Frontier Spirit movement and adventure and going to new places is a good idea. You got a passport if you're liberal. So those are some big differences

between the two poles. And is it, how much is that, do you suppose, is it preference for familiarity versus preference for novelty? Is that at the core? No, that's at the core. That's part of the neophobia. You could put that under the neophobia.

So the fear of ordinance dislike of new, and that can be new ideas. It can be new types of folks. It can be new discussions. All those kinds of things are avoided. And it's just, you know, most generally, it characterizes outside. Okay, so let me ask you a really specific question about that. Because you could think about that two ways.

You could think about that as avoidance of the unfamiliar and dislike of the unfamiliar, or you could think about it as marked preference for the familiar. And then on the other side, you could think about it as marked preference for the novel. you know, rather than it being, is it against something or for something, or is it both on both sides? It's both, I mean, the against, the against can go all the way to hate, you know, under, under, high xenophobia, hate, and even, you know, we get into how conservatism and traditional societies and so forth promotes intergroup aggression warfare. So the point where you not only hate those outsiders, you want to kill. And so you have both components that they are, the out group, the avoidance as well as the interest in socializing with people that will like you.

Okay, so we've got the values dimensions nailed down and so on to the parasite stress. Yeah, so when you start looking at conservatism, let's start there. The connections to parasites jumped out at us. And let me try to explain. So with xenophobia, okay, you want to avoid those people over there that are different from you, okay?

And that's, that's tied to a very fundamental part of a host parasite co-evolution. So the way host parasite co-evolution works is that it's ongoing and it's antagonistic. And the parasite is trying to evolve to eat the host. The host is evolving defenses against the parasite and that continues forever. You never get out of your host parasite co-illusionary race. So you get this co-illusionary racees and parasites? And much and much, much research shows how localized those co-evolutionary races are geographically localized.

So you get different strains of TB in different neighborhoods in a big city in Morocco, for example. It's geographically very, very localized. These host parasite co-relationary racists, which means that locally, you're relatively immune to the parasites, but the parasites on the outside, and those people on the outside, in the out groups,

those parasites, you're not immune to. So that's why you have xenophobia. It is a way to avoid foreign parasites that you're not evolved to deal with immunologically. That's xenophobia components. So that's contamination. It's avoidance of contamination. Right. And yeah from from parasites that you're not immune to because you're relatively immune to the local the local and you're set you're safe with people that are just like you okay the local people because they've got immunity like yours and yours is relatively good against the local parasites but not the foreign parasites because of this localization

of the host parasite coagulation rate. Right. And so you're saying you don't have to go very far away before you know, I've troubled far away. No, you know, all these new strains of COVID popping up, they're, you know, they're going to be lots and lots and lots and lots and lots of strains. And the, you hear about some of the strains now, they're 8 or 10 or something like that, but they're popping up and, and, you know, they're more of them. The surveillance on this new

strains is pretty limited so far. I haven't done a lot of that, could have been doing other things with a pandemic. But But still you get that, you get that occurring with the COVID too, this localization of the strains. You know, there's a South African strain and so forth, so on UK strain and all that. So you don't have to go very far, okay? For the localization of the immunity you have

to not work so well. And that's where the philipatric comes in too. So philipatric, you just stay home. You stay home, you interact with people that are immunologically like you and therefore are safe, relatively safe, rather than dispersing to interact with foreigners and the habitats that may contain

these parasites you're not adapted to. So that's a filipetric component. The etnocentric component is related to, so when the diseases come, you want to have a lot of local social support. So you have all these ties with extended family and so forth, that's your social support. And then ethnographic society, is traditional society,

is anthropologists have done a lot of research on how important it is to have kin that will help you when you get sick. That's the only way you can make it, have kin and kin and friends locally that help you when you get sick. That's the only way you can make it, have kin and kin and friends locally that help you. That's the epicenter component. So if there's a high probability of illness occurring, then you're more dependent in reality on your close friends. Exactly. The higher the parasite stress is in a region,

the more likely those parasites are gonna come eventually. And so you gotta have that social support that's important for dealing and getting through you and your family getting through the parasite crunch. So that's why the ethnocentrism, philipatri and xenophobia components. And those have, you know, the component of another part, you know,

subparts of that we talked about, open this to experience, new experiences, and all that that's part of really neophobia. Neophobia. So we, okay, so there's a personality. So in, I've got a couple of specific questions about that for you. So the best predictors of conservatism from a personality perspective are openness to experience low.

Yeah. And one sub aspect or one aspect of conscientiousness, which is orderliness. Now I noticed in your research, you looked at extroversion and openness together. And you saw that the more collectivist slash conservative types who are protecting themselves, according to parasite stress theory from contamination, are likely to be more introverted and lower in openness. And that means less exploratory in general. It can cause those two things together seem to maybe make up exploratory behavior. But there is good personality data showing that the orderly part of conscientiousness is

also a predictor of conservatism. And I don't know if there's been any data because that's a more microanalysis in relation to the component. data because that's a micro more micro analysis. Yeah, nobody's looked at that component, but absolutely. The orderliness is very fundamental to conservatism. You want order. This order is chaos on the standpoint of a conservative mind. You want order and everything. Yeah, and chaos is, see, I've thought, and this is interesting too,

because maybe we could talk a little bit about the emotions that are listed in here. So for the longest time, I had been thinking about the conservative collectivist viewpoint in relationship to novelty in two elements, two manners. One is that the more conservative mind doesn't get as much of a positive emotional kick out of novelty and exploration. Because that's fundamentally motivating if you have the personality type that's associated with exploratory behavior. But then there's this idea of phobia too, like neophobia. But you know, conservatives aren't higher in neuroticism. And so, and that's really a striking finding, because if anything, it turns out that at least under some conditions, liberals seem to be higher in trait neuroticism.

But there's a role of disgust that seems to be under examined. And is it, is the neophobia, a consequence of fear or is it a consequence of disgust, which seems more tightly associated with immunity, as opposed to say fear. Yeah, well, you know, you can, you can get prejudice toward an outrood that has fear components and disgust components. I mean, you can be absolutely disgusted, you know, how to consider a person who has to interact with an outrood, well will might even have to discuss face, not discuss it, but it's also worth it. I mean, I think you see that with food, for example. Yeah, right. You get to a food or any kind of pathogen threat,

can evoke a disgust, just in my motion of disgust, in a person and theust in a person, and the more conservative they are, the more likely to get the actual disgust reaction. Yeah, well, in disgust, I rate more of moral violation, food, rotten food, dirty toilet, all that stuff, yeah. So that's some account like people have struggled

for a long time to make sense of dietary prohibitions in religious contexts, for example. And I mean, if you have dietary restrictions and markers for in-group identification, that's a good way of deciding or of determining consistently who's on your side and also marking who's on the other side. Yeah. All kinds of things come into play to indicate boundary between entry now. Okay. So when I was looking at thinking about the relationship, you know, there's

five basic personality dimensions and 10 aspects. And so, but only two of them really, really strongly predict political affiliation. And that's openness. So high openness is liberalism and and and orderliness, which is less powerful predictor, but so the conservatives are low in openness and high in orderliness. And I thought why in the world do those two uncorrelated personality predictors co-vary to predict political belief? And then I thought over a number of years that it has to be, it has to do with borders. Is the fundamental political question is the conservative likes thick borders between everything. And the liberal wants thin borders and the liberal wants thin borders because their

niche is the locale where information is transferred. And but the co the the counter tendency is the conservative tendency to say, yeah, but if you're where the information is going to be transferred because the borders are thinned, you're probably going to get sick and die. And they're both right. Yeah. Seem reasonable. Yeah, right in terms of what is you sometimes the conservatives are right that you're going to die if you get if you expose yourself to what's new and sometimes the liberals are right in that you need what's new to renew you. Right. Well, these these vays that we acquire are very strategic and they're, you know, they're they're suitable for our understanding of the culture that we live in. They're suitable

for that. They're optimal for that. So if you take measures of parasite stress across the world, countries or states in the United States or whatever, that that will correspond to conservative or collectivist values measured by measured by political scientists, these measures and put in the literature for countries and states, measures of my psychologist of individualism, collectivism, put into the literature. So we pull those data and look for the predictive relationship between parasite stress and conservatism and liberalism and and found what we expected, and strongly so. The more parasites, the more conservative, said differently, the more parasites, the more collectivists. And so does that broadly mean the more infectious diseases?

Yes, and so, yeah, there's two ways, basically, we've measured, or several ways now, we've measured infectious disease levels. So by parasite, I mean, any infectious agent, it doesn't mean just intestinal worms or something, it's any infectious agent. So virus, bacterium, worms, whatever level of parasites you're talking about is a parasite.

Infectious disease, synus with infectious disease. So you can take number of infectious diseases per country, for example, you can take number of infectious diseases per state for the US, or you can take the rate of infection so that the proportion of the population that has each of these infectious diseases in an area.

So either number of infectious diseases or the prevalence of the infectious diseases. And either of those very strongly and similarly predicts the values with more infectious diseases, more conservatism that is more collectivism, the fewer infectious diseases, the more liberalism, that's done on just the geographic level. But then, and we did all that initially.

And then others came along quickly, actually, once it got started, and it's still really blooming out there, all the research on the parasites, stress theory values done by people all over the world now. But people start doing it at the individual level. So you take a bring a person into the lab and you show them cues of immediate parasite danger. So these are just like a slideshow with with disease cues in it. So a dirty toilet,

a person with skin pox, a person sneezing, those kinds of those kinds of cues. So they see these slides and then you measure their values before and after seeing the slides and you have an immediate effect, amazing immediate effect. So let me talk about the power of these relationships. So if I remember correctly, some of the data that your team generated showed that the correlation between infectious disease prevalence, so parasite stress and conservatism was as high as 0.7.

Yeah. So staggering unprecedented strength. That's stronger than the relationship between general cognitive ability, or it's as strong as the relationship between general cognitive ability and learning, which is the strongest association I've ever seen in social sciences.

Yeah, yeah. Yeah, we get some big effects as, and I mean, there's very, there are very in terms of what particular prediction we're looking at and we've looked across so many domains of human life that, you know, there's variation in effects as, but yeah, some of these effects are tremendous. And of course, we do, you know,

through standard statistical procedure, we do controls to potential confounders in all these analyses. So that's at the, you know, you do the regional stuff with countries of the world, states of the United States in relation to values and parasite level, but then this stuff coming along with looking at individuals, really is nice too, because

you got the same patterns and the regional level. Yeah, and the individual level. Right, so we should take that apart a little bit. So the problem with comparing nations is there's lots of differences between nations that might be correlated with parasites and so it's, but then if you go to the state by state level within a country, you control for lots of those variations. You have, you have. And also in your analysis itself,

you do statistical controls of things that potentially could be problematic, confounds, or whether you're looking at between countries or between states. at Confian, whether you're looking at between countries or between states. So we have data from all those levels. Some of the more recent stuff is coming out now. People are doing, did a lot with the slideshow that I mentioned. There were 10 slides that reliably evoke greater conservatism. But then now they're looking at showing people

like a short story about COVID, COVID's real serious in your neighborhood or something like that, you know. And that does it too. So do you think there'll be a swing towards conservative political belief in across the world? Because of the, because of this pandemic, will that shape the political beliefs of an Israel?

Is there a crucial period for that to be shaped? So for example, will this have a bigger effect on say 14 to 16 year olds or 16 to 18 year olds who are catalyzing their identity. Would you would would there be a cohort that would be most effective? That's a really interesting point. And I've thought a lot about it. We don't there's no there's no data on that now.

So if you I mean the way that you could empirically attack such a thing would be to look at, to look at people of different ages in relation to like the effect of these experiments on them. Do you get a bigger effect size when you show slides, disease slides to one age group versus another? Yeah, or would last a major. Yeah, our last one.

We don't know how long it lasts either. That research surprisingly has not been done. You bring people into the lab. And you show them these slides and you get the effect. Also, one nuance of that is if you measure what we call the perceived vulnerability to disease, that's a 14 item questionnaire that's validated and measures a person's concern about infectious disease and that's an individually variable thing. More conservative people are the higher their score on that, of course.

And worry about infectious disease. So people that are high on this going into the experiment show a bigger effect when they see the slides. They shift more in terms of degree of conservatism. Do you do you know if there's any effects of personality on that? So if that hadn't been looked at hasn't been done yet, but it would there would be some covariance there because the people that are high and worry about infectious disease are basically conservative people. So they're going to have less openness to, you know, new things and more introversion and all that kind of stuff.

I'm really yeah. So when I first came across your parasite new things and more introversion and all that kind of stuff. So when I first came across your parasite stress hypothesis, I was reading a fair bit of the literature on disgust generated, fair bit of it by Jonathan Height and his research team. Because he was one of the first psychologists to look at disgust as an independent emotion. But I was reading a book called Hitler's Table Talk, which was a collection of his spontaneous utterances at Meal Times collected over about three years. And it really affected my reading of it because the number of times that he referred, that he used parasite metaphors really stuck in my mind. And I started to look at all of the Nazi propaganda from before the Second World War,

in terms of parasite stress hypothesis, especially after I also realized that Hitler's extermination campaign arguably had its origins in public health policy because they started out with tuberculosis interventions and then they went to clean up the mental hospitals and so on. And like the, you know, and Hitler went on a factory clean up binge, essentially, after coming to power. And they used

as variant of cyclone gas as an insecticide in the factory cleanups. So this was all quite terrifying reading what you were writing and reading this at the same time. And I don't know what you, I mean, I'm going to ask you to comment about that, what you think about that. But there's metaphor for parasites. That's that's a fundamental metaphor that that Germans, the Nazis, send to view themselves as under assault by parasites. Did you do?

Mussolini was the same way. So you said Mussolini was the same way. Not exactly the same way. It was just a replica of Hitler or a replica of him. Mussolini was, you know, his fascist dictator of Italy when Italy was fascist and Hitler fascist leader of Nazi fascism. But Mussolini, he for example, outlawed handshaking in Italy. He does the most disgusting thing to touch a person's hand. He was as much germophobic as Hitler. And Hitler bays four times a day. That's still going on in some parts of the world. in these 30-minute showers in the Middle East, people talk about where you get

the highly conservative people that really clean up. But with regard to fascism, I've been very interested in fascism, of course, because it's over there on an extreme pole of conservative end of things. It's got all the components of conservatism in writ large. And so I've been interested in the origin of fascism in in Germany and in Italy and Japan about the same time, the three, the three big fascism, to have been some other fascisms too.

I'm just been some other fascisms too. But a recent study you'd be interested to know has looked at infectious disease in German regions, cities, in relation to voting for Nazi, for Periedler's party, Nationalist Socialist Party. And the more, the way it works is, so he had, he has data from 1918 to 1920 the number of Spanish flu cases in all of your... I never thought about Spanish flu as a contributor,

because that came right after World War I, of course. Yeah, right after World War II. It was one of the things that devastated, I'd already devastated Germany. Yeah, and Germany, yeah. In the world, in general. Yeah. Yeah.

Germany was really hit hard by the Spanish flu, as Italy was to. And what this guy did, he got data, there's a data collection managed by the University of Michigan on the data from Third Reich and before the Third Reich became before the Third Reich became officially a Third Reich in German. And these data include the number of cases of death

due to Spanish flu in all these German cities. Also, they got a number of deaths from plague and tuberculosis and so forth too. tuberculosis was still a big problem by that point too. Wouldn't just, wouldn't just Spanish flu, but if Spanish flu was the main killer, but tuberculosis probably number two. Plague one, a big deal by that point.

So these data, these data have number of votes in these different cities for the Nazi party. They have the number of votes for the Communist Party and number of votes for various things. So the Communist Party was considered extremist then, as was the Nazi Party. And the votes are from the year's 1930 to 1933, I think. So the critical years for the rise of, for a really Naziism to rise of, for a really Naziism to get being there. And the more, the more people dying from the Spanish flu in 1918 to 1920, in a city, the greater the vote for the Nazi party in 1933. 33, 33. So, so that's a connection that's that was of interest to me. And this paper is just this recently appeared. Any idea about the size of the relationship and what about economic

are there are there are the confounds of economic well-being in the cities? Very important. He controlled he was able to control through the same data set for employment in those cities and for average wages in those cities. Two variables related to economic state. I mean, that's the traditional thing. Historians will tell you, well, the Germans were so economically distraught that they bought this stuff, you know. But the parasite stress theory values adds a new new mirror here, I think, for for fractures. And Italy have searched and searched for data on on flu death in Italy, but I don't think there's going to be anything like it. For some reason, a third Reich has collected lots and lots of data. Somehow University of Michigan, I don't know the history of the acquisition by the University of Michigan of these data, but it is a

reliable data source that is used now in sociological research. A youth studied other elements of parasite stress theory too. It's relationship with altruism, to relationship with human cognitive abilities. Yeah, yeah. So, yeah, we did study of IQ and relation to parasite stress and across the world and across the states in the US. And that worked out very well. The thinking was simply that if you've got,

you know, you think about that human immune system, it is tremendous. It's everywhere in the body. And it's very, very costly system in terms of the energy and in terms of tissue to make and maintain this immune system. Humans have this huge brain too, very sophisticated nervous system, there's very costly. So we assumed that these two components of the body, immune system and nervous system would trade off. And so under under high infectious disease, you got to make a good immune system or you're going to die. But that's going to cost you in terms of neural development and so forth. So we predicted that more infectious disease, lower IQ, predicted it for across regions of the world, countries and states.

So we went to the IQ literature, which is massive. That's a big topic in psychology, as you know, study of IQ. And there were data for essentially all the countries of the world. And there were data for the states. And we pulled those and looked at the predictions. And the predictions were met for both cross national predictions, about 0.8 between parasite stress and IQ.

More parasites, lower IQ, about 0.8. For the US, it's about 0.7 US states. Within states. Yeah. Between the 50 states, you take average IQ. Okay, so let's pull back just a bit for everybody. I mean, it's important for everyone who's listening to realize just how important a role infectious disease actually plays in the shaping of human evolution, cultural evolution included. So, for example, there are estimates, correct me if I'm wrong, Dr. Thornehill, but there are estimates that 90 to 95% of the native inhabitants of North and South America died as a consequence of contact with Europeans because of the transmission of measles, small pox, and mumps, primarily, although they were also prone to many other diseases that were brought in by the Europeans who had lived in tight packed cities, often with animals as close companions, had had had what would you say exposure to a wide variety of extremely toxic diseases developed

immunity, but then brought those diseases to the new world and basically decimated the entire population. Right. So this is a non-trivial event by any side. The Europeans, by the time they started moving out of Europe into the new world, the Europeans, I mean, they had all their diseases, but they had relative immunity to lots of risk toward diseases, turns out. And so they brought all that stuff over here and killed most of the native, new world people. Yeah, the great most.

I had read that when the pilgrims hit Plemith, the natives were desperate to see them because they had lost so many people, they couldn't harvest their crops. Yeah. Yeah, it was a mess and continued to be a mess a long time. Right. So when isolated populations of human beings have come into contact in the past, the upside is the trading of cultural resources, essentially, and that can be a tremendous upside. But the downside is the extension of infectious diseases. And we're caught between those two catastrophes,

well, those two, an opportunity and a catastrophe, which present themselves simultaneously. Yes, openness and just liberalism is great in terms of its benefits. You got interaction with lots of different kind of people. You get a bigger social network, got a bigger mating pool. You know, you don't care if they're different from you.

You wanna interact with them. And you can innovate out of catastrophe. Yeah, new ideas, new ideas, innovations. You coming from the outside that you can use locally, but that only work under low infectious disease because we get high infectious disease, all that outgroup contact interaction, okay. Yeah. Yeah.

Well, that's exactly what we've seen in the last two year and a half, two. Yes, absolutely. So we're right in the middle of it. And the mortality, you know, the more human mortality from infectious disease before the pandemic was still greater than any other measured source. So there's a recent work that's looked at, you can just sort of summarize it this way. You can look at you can look at genes that are that have that play known roles in human life. So their genes associated with immunity and those have been described by immunologists, which, which genes are involved. They're genes involved in diet. The genes involved in digesting, protein and all that kind of,

so all these, you know, gene functions are known. If you then you, you look at where in the human genome there's the most turnover of new alleles, new genes. Those are genes that are evolutionarily very active. It turns out that the immunity genes are the evolutionary hotspots in the human genome. And that says there's more mortality from infectious disease than from other measured problems that humans face. Most mortality still is from infectious disease. That was done at 50 sites, human sites throughout. So that provides evidence that that's actually the worst threat facing the world's threat. Yeah. Hence, hence its powerful effect on such things as values. Absolutely. Absolutely.

It's the main mortality factor. And if you look at the anthropological evidence about the importance of infectious disease versus other things, there's a lot of evidence for that. A nice review recently that some people did. But infectious disease is the main killer of infants and older children in the ethnographic records of traditional societies.

Infectious disease is the big one. Next is infanticide, that's number two, for parents killer kids strategically, because they can't raise them under resource limitation or the kids are sick or whatever, in phanicides become, that's number two, but infectious disease is the main killer. So, okay, so here's some radical ideas, I suppose,

because reading all this, learning this, okay, before we go there, let's do one other thing. Main objections to the theory, practical and empirical. What's, what, I read a paper recently, and I'm afraid I can't cite it in detail, but it'll serve as an example, claiming that with proper control for technological development, the causal or the effect of parasite stress on political belief vanished. Now, you cite many, many papers in your books and in your paper. So I know me saying that this is a canonical study, but it's very used. This is a very, very, very, very provocative theory. I mean, it op

ends in some sense. My sense sense when I first encountered it, was that it op-ends almost everything we think about politically. And so, and what's the saying that extraordinary claims require extraordinary evidence? We've got to look at the counter evidence too. So what do you think are the main weaknesses of the idea as far as you're concerned

and how have you addressed them and have they been successfully addressed? Yeah, we've addressed them as they have come out and the parasite stress theory of values has gotten when it first came out, it got so much attention that that attracted a lot of people to try to falsify, you know, and that's the way that works in science. Yeah, I think so. We went through that, we went through that phase. And now all the research is looking at very interesting spin-offs in productive ways of the parasite stress theory.

And no criticism said come out recently. But the kind of thing you're talking about where it's really a modernity, modern things and so forth. That controls our bad. That's an old idea in the literature that basically people just get more modern, they get more liberal and so forth. And we take that on in a number of ways.

And the one way I'd like to, you might be interested in, we look at the cultural and social revolution of the 60s and 70s in the West. So what happened, and I was there, you had a liberalization of baggage, basically, as a bottom line, but you had more, you know, more, you know, the women's movement started then there was a sexual revolution, same time. Right. Which aids put the, put a terrible crimp in,

another infectious agent? Yeah, and ethnic groups, that minority groups that had been ostracized and so forth got more attention, positive attention. It was democratization of law, or voter laws and all that change. So it was more than just people talk about that time as the sector revolution time, 60s and 70s.

But really, it was a much broader social revolution involving human rights, increasing human rights and liberties, basically liberalization. So what the hell happened? Well, here's what happened. It was infectious disease changes that began in the 20s that led to all these liberals in the West in the 1670s. And these infectious disease changes are well done. To the control of infectious diseases like malaria. Yeah, well, we have bigger than that. It started out in 1920 with chlorinated water. That started in a way. So we're talking about the rest of the world in change.

They didn't go through the social revolution. Many places in the world still have it because of disease levels are high. all the Africa, basically much of Asia. But 1920s, chlorinated water started in the West and quickly spread throughout the Western world. By the Western world, I mean, US, Canada, Western Europe, Australia, New Zealand, those places. So, so, chlorinated water, and that knocked out lots and lots of infectious disease, put a little chlorine in public water. Also in the 20s began some systematic garbage collection before people just threw the garbage out of their hailing. four people just threw the garbage out in the hailing. So each treatment plants started the end two and there was more indoor plumbing in the starting in the 20s.

Now let's jump to the 40s. 40s big, big changes with regard to emancipation from parasites. Had child vaccination programs that began in the 40s. Also antibiotics, first good antibiotics right after World War II, 1945, in the 40s. So this was really by that point a new world in terms of lower infectious disease compared to the world that all generations of humans had experienced in the West prior to those 20s and 40s. There were some antibiotics in the 30s, but sulfa drugs and so forth, but they

had terrible side effects. So the real good antibiotics didn't come along until the 40s and broad spectrum kind of antibiotics. And of course, that spread so rapidly that the use of antibiotics that quickly saw resistance to antibiotics popping up, you know, the evolution of resistance and parasites. Yes, which is a serious problem we have now because we have diseases that are resistant to almost all the broads, bads and even in carcass. It's a looming catastrophe, which we should obviously pay attention to. Right. Arms raised between the parasites and the drug companies now with that. So up to the 40s. And then also in the 40s, you had insecticides coming along.

Good insecticides, chlorinated hydrocarbons, and organophosphate, insecticides that heal uh, HESPACES, including mosquitoes. So, uh, vectors, uh, important vectors of disease in the, in the, uh, in the West, mosquitoes, uh, so the knocked out malaria, knocked out yellow favor with that. And, um, and, uh, So, it knocked out malaria, knocked out yellow fever with that.

And so, all that was going on to emancipate people. And then the generation two or two later, you get the rise of liberalism throughout the West. So, all these liberal young people growing up in a relatively disease-free environment by all these health interventions became the hippies. They were healthy enough to be free. Yeah. And so that does really raise the question again of what COVID, this COVID pandemic and the lockdown is going to do to the political temperament of the West or the world for that matter. But it's a particular change in the West because we're not accustomed to this sort of thing anymore.

It's so interesting because of course I've thought of the liberalism revolution being a secondary derivative of the birth control pill, which is a biological revolution of immense magnitude, but I hadn't ever considered in depth even after the use of birth control and all that by women. That takes some willingness to try new things. Right, exactly. Well, that's it. That might be dependent itself on, yes. That's a way from tradition, you know, taking birth control. So there's another perverse implication of the theory that you've developed, too, which is that conservatism, insistence upon hygiene and disease prevention is a precondition for liberalism. If it's successful, right?

So it's in some sense, the conservatives are battling off the disease so that people can stay healthy. But the consequence of that is as soon as that they're healthy, they become liberal. Yeah. Yeah. God. Isn't that something? Yeah. Well,

I think it's here's you can look at it like this. So if you've got how conservatism in a place, then those conservatives are doing things that promote promote, well, they're not, they're not, they're not using modern technology, they're not, you know, open to new ideas, they're not open to science and all that. So those are attitudes that help the infectious disease really. Right, right, right. Right. So they're reliance on traditional, that's right. Traditionalism also an impediment to tremendous impediment. It reduces their contact immediately. So it works against them that way. I mean, if you're not, you know, pro science and open to new ideas and innovations and

all that kind of stuff, that is tremendous limitations. And so, you know, you know, you put in septic tanks and you think, or chlorinate the water. Okay, so, so another high-pacetion, you don't get a vaccination. Right. Well, okay, so let's talk about two things, then. One is, I've been struck and tell me what you think about this. The COVID has become a politicized issue in Canada and in the US, but it doesn't seem to have happened the way you might have predicted if you were relying on parasite stress theory, because it seems to be that the conservative types are the ones who are objecting most strenuously to the lockdowns and to the inoculations, whereas the liberal types, I mean, and maybe I'm wrong about this, but seem to be more in favor of the restrictions of movement and so on. And that actually, I know I can't get my head around that exactly.

Yeah, no, you're right. That is the pattern. And that's been studied now. And you know, there's some papers on it. And here's the way, here's what's going on. I think. And here's the way, here's what's going on, I think. In the US, in particular, the conservative government at the time, when COVID was getting off the ground, the Trump administration, was very negative about COVID. I mean, he called it hoax and all that didn't believe it and no problem. And so that is the authority. We need to talk about authoritarianism because here's this is where it comes in. You have the king, Donald Trump,

saying that it's no problem. This disease is no problem. And it's just gonna go away. It's a hoax and all that kind of stuff. And that is the word from God, basically, to highly liberal, highly conservative people. And that's the way authoritarianism works. A people that are highly authoritarian,

and that's conservatives, that's strong, there's a lot of evidence there. Authoritarianism is very highly correlated with conservatism, in fact, a component of it. The more authoritarian the people are, the more likely they will follow these guys that they label as a leader and to the point that they'll follow them anywhere the follow them off a cliff basically as

they did in in Germany as they did in Italy and as they did in the United States during this COVID day. So you believe that what happened was that the evidence that there was in fact a dangerous epidemic was rendered non-credible. And so conservative tendency to prevent the disease didn't kick in. That's right. Exactly. And do you think that's a good point?

The president was the authoritarianism that conservatives are carrying. And had Trump acted another way, you know, said, this disease is really important. I want you folks to wear a mask and be careful in distance and all that kind of stuff. Then there would have been a different outcome because that would have been the authority message. So it's one, it's one element of authoritarianism slash conservatism interfering with another. That's right. Okay. Parasite stress and sex. Yeah.

There's been some look at values in relation to sex, so conservatism. Conservatives are conservative. There's old studies that there's one paper I should send you. You've got all kinds of correlations in there with everything on the Sun in relation to conservatism and liberalism. But you know, interest and different positions, copulatory positions and all that. The conservators more likely to stick to the missionary style and whereas the liberals are more adventurous with regard to positions. And is there a relationship between adventurousness in sexual position and the risk of transmitting sexually transmitted diseases? But, you know, liberals are more interested in, be more interested in partners that are in different ethnic groups, and the nest been studied, you know, limit your sexual interest just to your in group,

if you're liberal, you're happy with people of different color and different backgrounds, and all that kind of stuff as sex partners. So, so those kinds of things have been done with regard to sexual behavior. We did the variable social sexual orientation. It's a variable, it's validated in psychology and it measures really a person's attitude about promiscuity or sex without commitment to call it sex without commitment.

And that varies among individuals. They're attitude about sex without commitment. their attitude about sex without commitment. And we looked at their data on, I think it was 120 countries measures. So we took those data and looked at them in relation to parasite stress and values. And the more parasites, the less interest that women show in non-committal sex, so the more parasites. And that's mediated, I presume, by a cultural response to the presence of the parasites. Yeah, that's concern. Yeah, and I will have any studies been done that are analogous to the the political studies where where people are shown images that are reminiscent of of parasitic

presence and then asked about their sexual preferences with regards to monogamy or uncommitted relationships. No, that ended up. No, that ended up. Now, there's a PhD thesis for relationships. No, that hadn't been done. No, that hadn't been done. Now, there's a PhD thesis for someone. Yeah, we just did the, we just took the SLI data, social, sexual orientation, inventory data for men and women across these countries and looked at it in relation to parasites, and values. And as I mentioned, as infectious disease increases, women show more restriction. And it's women specifically? Women specifically. The effect for men is not reliable. This is not very big and probably not even reliable, statistically significant. But for women, it's highly significant. For more parasites, the more restricted women are. And that goes along with conservatism.

So conservatism, there's a set of purity and protect the jewels kind of attitude that is instilled by a conservative culture in women. So in women, well, so there's a question. Yeah, it's okay, you know, it's a double standard. Well, when you get parasite stress increasing, then is the conservative proclivity manifested to begin with in the women and then spread to the men? I mean, because they're more primarily concerned, let's say, with sexual contamination. I mean, the role of the genders in determining the manner of change, the

men are changing and other components. So they men are hot to try regardless of their... Well, that's what I was thinking. But the men are changing in terms of becoming more as an affiliate and at the centric and those kinds of things. So the sexual changes don't drive the rest of it. No. Because I mean changes in sexual behavior often drive the rest of it. No. OK, because I mean, changes in sexual behavior often drive changes in other phenomena.

It'd be important. Yeah. Yeah. You also write about parasite stress and religiosity. Yeah. We did a big study of that looking at religion scholars looking at their data on commitment and participation of people in religion across basically all the countries of the world. And we had state data too, and US state data on participation and commitment of

people. And predicting that more parasites, more religiosity, measured either as commitment or participation and more conservatism, of course, more religiosity, that's well known already, more conservative people. And then those would be traditional markers of religiosity like church attendance, such as church attendance. Yeah, rather than spirituality per se.

Number of times a month you go to church and stated commitment that you have, do you believe, do you believe in the local religion, that kind of thing. This religion scholars, you know, have done a good job and then published all that in the literature. So you can pull their data and then look at it in relation to parasite stress, more parasites and more religious. People are, and we expected it from following ideas

that was known that religiosity is very tightly correlated with conservatism before. That had been shown by lots of folks in the past, but religiosity has a couple of parts to it that were of interest to us from the standpoint of the parasite stress theory. One is the boundary issue that religions often show. So in fact, religion scholars define religions in terms of boundary. So this group over here believes in this God, the group over here believes in this God, and group over here believes in this God are gods, and so forth. So those are boundary markers.

Those boundary markers. Yes. And so the boundary would be like a xenophobic kind of function, you know, to end group out group kind of separation. The other part of religiosity that was an interest from the standpoint of the Paracetus teres theory is the Adnocentric part. So you get that in group binding with your colleagues at church and so forth that can be extremely strong. And so that we looked at it and found that

you basically a new theory of religion, more parasites, more religiosity across countries, the world and states. And what sort of effect size is that? Those. I don't remember offhand big effects. I mean, we published in a major brain of behavioral sciences, major top-tiered germs. and it was, we published in a major, brain of behavioral sciences, major, you know, top to your journey. But again, you could, you know, back to your earlier question

about showing people these immediate parasite threats with slides or some other way that they're manipulating that now, they're doing all kinds of things with that. And see if people get leaving God more or something like that. Immediately. That would be cool. Yes. Yes. It would be. You changed it. It's a belief in spirits by by that.

Well, you also wonder too. If, you know, I'm just thinking here, ideas are just flashing through my mind about beliefs and spirit to begin with because the belief in spirit causing illness, for example, is sort of an early analog of a disease theory. Yeah, yeah, I mean, people were all, yeah, there's a study that I can't remember exactly what it is. I've got it on my pile over here. The claims that the fundamental belief we have in a spiritual world really boils down to spirits as diseases. Yes, disease causing entities. They are invisible agents that are trans-indiscible.

But you can transmit them too. Yes. The evil eye and all this other stuff in cultures that suggest transmission of this spirit. And of course, before the germ theory, before germs were known, parasites were known to cause disease, it was all invisible. So, spirits feel that.

And, which is, you know, as, as, which is as channels for the evil that these spirits have. That's part of it too, into inquisition and so forth. And so all that sort of cool. And everything that's unknown, right? Because the well that end is. Well, it's down to a disease. Right, right, right.

And there were right, the disease was killing everybody. Most of the people, anyway, you know. So, yeah. was killing everybody, most of the people anyway, you know. Yeah. Well, you know, that was all actually too interesting. I guess I'd like to close with this. So you've been studying this a long time. And it's very I mean, I'm not going to be a person who is not going to be a person who is not going to be a person who is not going to be a

person who is not going to be a person who is not going to be a person who is not going to be a person who is not going to be a person who is not going to be a person who is not going to be a person who is not going to be a person who is not going to be a

person who is not going to be a person who is not going to be a producing for about five years, I would say maybe 10. It hasn't permeated my thought system entirely, but you've been wrestling this with this for three decades, two decades anyways. Absolutely. And a sense on my life. Let me explain. I was born and raised in the old South, heart of Bixie, Alabama.

So I was born into a culture that hadn't really changed in 100 years, except they had cars and stuff, but ideologically there would be no change since the Civil War. Very conservative place. And for reasons I may, you know, I think about a lot how come I came out of it liberal rather than not conservative. I would say, you know, I would find what these people were doing day in day out, a senior face all the time if you live in a conservative culture, the inhumanity. And why are they doing that? And what's wrong with you people, that kind of thing. And then finally, Hill, I just decided, I was gonna step back and just try to think about it, study it.

And I finally got around to that in my scientific research, most of my research was on sexual selection processes and so forth. I only got into the bay, you stuff about year 2000. And so I've had this very, very strong interest in how these people I grew up with, got to be that way. Then when I went off to university, I went into a relatively liberal place. So I was then I became interested in how these people,

how these liberals got there, got their mindset too. I was more like them. So I go back a long way in my interest in this. And they, you know, So, I go back a long way in my interest in this. And it's just, it's been really satisfying to understand, to cause, to do the science on it, and really understand the causal stuff. And stuff that happened in my family and so forth.

I mean, I'm trying to do a popular book for the intelligent reader on all this. But it was one incident where in the old South, middle class, upper class families, white families, would hire a black woman to raise the kids, or black women to raise the kids, or black women to raise the kids, and my family did death. And I was closer to this woman really in many ways

than I was my birth mother. And she died when I was 13, my black mom died. And she got sick, and my family wouldn't let me go see her and she was sick because she was sick and they were conservative and they were worried about me. I mean they were trying to protect me but I didn't understand that at the time and in my mind she was my mother. She raised me. She was with me every day and from time I was born until she died, which is 13. But I couldn't

go see her. And finally, let me go to her house. She lived in a little shack, wouldn't shack on the other side of the tracks, so to speak. And because it was regional segregation, everything was there. And so I got to let me stand on the porch and talk to her. She was inside in the bed dying, but I could talk to her on the porch. And we talked and she died five days after that. And they didn't even, my family wouldn't even allow, didn't even tell me whether she was buried and so forth. I mean, there was that level of conservatism and worry about disease and I'd go to her grave or something and catch a disease.

But this knowledge of Bayes has helped me with his things like that, events and there are lots of them in my upbringing that were devastating because of the conservative values that I was dealing with terrible things happening. And so I think that's one thing that really has sparked my interest in values. And then, of course, I'm liberal now, how do I get that way? My high school, I was a high school, the cater Alabama, is where I grew up, my high school of graduating class, about 200. And there were about three liberals in the class. I was one of my close friends.

He was liberal. He's a civil rights lawyer in South Alabama now. And another one, Frank close friend of mine, she was the one she works for the Democratic Party and what she would be seen. But most of the rest of them were pretty conservative and I wonder how I got out of this. And my hypothesis is that I had an interesting genetic constitution because my part of my family was Native American.

And so Native American in North Alabama, Cherokee, and so those folks had the local immunity to the infectious diseases that were endemic to that region, the Native Americans. So I got that genetic complement and I also got the European genetic complement, which had pretty good immunity to lots of respiratory diseases. And that's another story. There you go. But so I got this this odd genetic complement, Native American plus northern European, the Thorn Hills, the northern European. And that that reduced my interaction with infectious disease growing up. So like, unlike the kids around me, I didn't have all those ear infections. I didn't have all those

eye infections growing up. And unlike most of my friends. And so I think that's it because I think that's part of the ontogeny, the developmental background of the values. That is you're going through, you're going, you're growing up and how often is your immune system activated and how long is your immune system activated when it's activated. That's part of the developmental background that we propose for for values. If your immune system activated a lot and you end up conservative, it's not

you end up liberal. So I think all that is is part of my interest in this. If I've been born somewhere else, maybe I'd never got interested in values, then in the old sounds, you know. Well, I think that's a really good place to end. I don't want to end because there's like 50 other things I'd like to ask you, but that's been very talking with you. Well, thank you. It's so interesting. Your research is like I said, it's too interesting, actually. You suggested some good experiments to know the thing about. Yeah, yeah, well, they're causal experiments and they're actually relatively straightforward. I'm supposed to be retired now. But I'm trying to do this popular science book. It also be interesting to see if there's any relationship between

even self-reported prevalence of amount of time ill during childhood and adolescence and trait openness. There is a scientific study of illness, two studies of illness during childhood reported illness during childhood is one of the studies and some some components of conservatism. I don't remember if the openness is there, but some in networks and then there's another one where they had they looked at actually health records of children who then became adults, and have adults, and then you have their health records, and they did that and showed that the less health the kid had as a child, more conservative they were.

So that kind of stuff is out there. So then, okay, so maybe we could, let me ask you what you think about this. When I first came across your work, I thought, is it possible that the human race could rescue itself from the worst excesses of the kind of conservatism that degenerates into malevolent fascism essentially by wiping out infectious disease?

I think the answer to that is straightforward yes. Jesus. Yeah, absolutely. The, you know, I want to emphasize that's a parasite stress theory of values. Parasite stress theory of values and sociality is a sound to theory, enhance. It doesn't have any,

doesn't make any moral judgments about, you know, it doesn't say conservatism is more moral than liberalism or vice versa, scientific theory. No values judgments involved there because of scientific theory. But if one wanted to change the values of the future change the values of the future of people. Then you have to know, of course, what the causes of the values are. That's why you change things. You know, causes of things and you can change them. Then if you wanted to make the world more liberal,

you would reduce infectious disease. Well, you can say, imagine you wanted to make the world a place where the cost for the free exchange of ideas and people was dramatically reduced so that the countervailing tendency to that was unnecessary. Yeah. And the catastrophes that might go along with an excess of that countervailing proclivity. The most effective way forward would be to eradicate infectious disease.

And so, and then you'd have the benefit of eradicating the disease, which would be non-trivial, plus you'd have the political benefit. People be healthier, lower morbidity, and healthier throughout their lives. And also they'd be open and, you know, sort of reaching the goal of the true enlightenment, which was all about, you know, freedom of thought and individuality, science, knowledge, all that stuff.

Right. All entirely laudable goals, except when the cost becomes too high. Yeah, when diseases are out there. Well, so I've been talking to people like Bjorn Lomburg and Matt Ridley and, and, and, and I don't know. I know there, there are people who have a positive enlightenment view of the future and are having a hard time in some sense along with the rest of us generating something like what would you say, a noble

vision for the future that moderates could get behind and be motivated by. And it certainly seems in light of this discussion that and of what's happened with COVID-19, et cetera, and the fact that infectious diseases are still a primary killer. And not only that crippler of people all around the world and that they contribute radically to all sorts of political instability that one thing we could all agree on would be that less infectious diseases would be better. Yeah, absolutely, absolutely.

And I have a pretty positive view of the future. Like you've noticed on your website that you interviewed Steve Pinker. Yep buddy. He's in the same group in some sense as these other people that I just mentioned you know they're they're optimistic enlightenment figures. I can be optimistic and and he has data on how much things have improved over the last several centuries and that's because of lower infectious disease. I mean, he doesn't have a theory. His idea is, it just stops it. He'll think people got enlightened.

But how come they got enlightened? You know, Wendy and Lightman occur. And why did we allow it to occur? Yes, exactly. That's the real one. Absolutely. The better and better wanted mortality and, you know, homicides and wars and all that reduce infrequency. And all the evidence we put together says it has to do with lower infectious disease to time. That's what happened. That's what's behind that tree. And that's why that's that's that's the key to our better angels.

Thank you very much. I appreciate it was great discussion. I really learned a lot and your work is to be remarkable. You want to take? Yeah well I may call on, may we'll call on you again. you