This podcast is brought to you by the Albany Public Library main branch the generosity of listeners like you. What is a podcsat? God daddy, these people talk as much as you do. Razib Khan's unsupervised learning.
Hey, everybody, this is Razib Khan here with the Unsupervised Learning Podcast, and I am here with the you know, I say a very special guest. But this is a very special guest, in my opinion. I'm here with Steven Pinker, who is the writer of many books, among other things. So he's coming out with "Rationality" right now. "Enlightenment Now", Better Angels of Our Nature", "Sense of Style", "Blank Slate", "Language Instinct", "How the Mind Works", "The Stuff of Thought"... And I think there's a couple of other ones I see out there. But those are the primary ones. And I do have to say, for the listeners, I know "The Languages Instinct" is, is, you know, back in the 20th century, but I think that that book in particular, was probably like, my favorite. Even though "The Blank Slate" was way more accessible to me and super influential. I think "The Language Instinct" is just like, really great, because it's introduction to a field that is not, you know, part of my core knowledge set, and I thought it was really great. So Steven, could you introduce yourself to the listeners?
Sure, can. I am a professor of psychology at Harvard University, I've taught at MIT and Stanford in the past. And I'm interested in all aspects of language, mind and human nature.
Yeah, and I think people know that from your body of work, and all the books, right now, you're writing a book on rationality, or you have a book on rationality out, you know, and it's, you know, like, how we think, right? Why now, like, you know, I, I know, some of the stories of like, you know, why you, you know, wrote your book on violence in terms of how people didn't really understand the decline? Like, I mean, what's going on with rationality right now? I mean, I have some thoughts too, but I want to hear your thoughts.
Part of it is that the the issue is timely. And the frequently asked question that I get when I first when I told people I was teaching a course on rationality, and then when I told them I was writing a book is, why is the world seem to be losing its mind? Why is why is there so much fake news and conspiracy theories and paranormal whoo whoo, and quack cures is that there were just a irrational species through and through or has something changed in the the environment in the drinking water. So that was one impetus. But also, like a lot of scientists and social scientists, I've long thought that some of the tools that we use to try to improve our thinking, are just tools that every educated person should, should have at their fingertips should be second nature. Just what we call Bayesian reasoning was the best way to calibrate your credence and a hypothesis based on evidence, signal detection theory, how do you trade off misses and false alarms when you are trying to determine whether something is out there in the world based on noisy evidence. Logic. And even though there, there are curricula, sometimes called critical thinking, there isn't like one place where you can brush up on the rudiments of logic and probability, and correlation and causation and game theory and rational choice theory. So I thought it'd be a useful service to write a popular science book explaining those theories. And also, at least implicitly, I wanted to make make the case for rationality, that rationality is a is a good thing that we should all we should cultivate it in ourselves, we should promote it in the public sphere. And just making it a thing having a book with that title. And and and I do have discussions on the somewhat paradoxical challenge of how do you make a case for rationality, given that if you're making a case for anything, you're already committed to rationality? But that's part of the point.
Yeah, yeah. I mean, there's, yeah, it's interesting, because the rationality as a term and an idea has, I think, general positive connotations, but in terms of the execution, you know, our species and we as individuals leave something to be desired, I think, but you in this book, seemed to be holding a position that, you know, kind of we are fundamentally rational beings is that would that be a correct description?
Well, we have we have a capacity for rational that that is what makes us such a weird species as far as mammals go. And it is I deniable that we are a is all zoologically unusual species and the extent to which we use our brains to shape our world quite literally, we've shaped the world and we've infested the whole planet, because we We've figured out how to survive in niches that we weren't particularly adapted to. And even people who hold the most florid, wacko conspiracy theories, you know, they they hold a job, they can keep gas in the car, they get the kids to school on time. So it's not as if they're stark raving mad. So there's got to be something about rationality that accommodates both what our species clearly is capable of, but also the weird beliefs that are capturing so much attention.
Yeah, and I do want to get to those. But one thing that I do want to ask you, I feel like he's probably peaked around 2010, maybe a little earlier, maybe later, there was a vote for a bunch of books, and I read those and I was interested, that basically talks about cognitive biases, just you know, the heuristics where we understand the world, and, you know, books with titles like predictably irrational. What were you thinking at the time as a working psychologist, because I think that those books to a great extent, highlighted for a lot of people how we don't think rationally, and it kind of changed. I think, the public priors in terms of expectations. I mean, a lot of it had to do with for example, why did the financial crisis happened? Why did these people behave so irrationally? Like, what's going on? Well, how do you look back at that now like 10 years on and what did you think at the time?
Yes, and of course, the the prototype is Daniel Kahneman's "Thinking Fast and Slow". And Danny was, is one of the pioneers of the study of human judgment and decision making with his late colleague, Amos Tversky. He won a Nobel Prize for the work and where he published "Thinking Fast and Slow", just about 10 years ago, almost exactly to the week I think it was. He was telling a story that others like Dan Ariely with "Predictably Irrational", Tom Gilovich, Why... "[How] we know, what isn't so" Massimo can tell you, Palmerini, a number of people had been publicizing work like Tversky and Kahneman before Kahneman and finally had to say but you're right, it did peak about 10 years ago. It's partly behind the political movements, sometimes called 'nudge' or 'behavioral insights' to take advantage of human irrationalities want to get either to exploit them or to better still to nudge them in the right direction so that without authoritarian structures, they naturally do what happens to be best for them. So I think you'd like a lot of cognitive psychologists, I've been teaching this for decades, and it's great fun to teach, because there's so many great gotcha moments where you you give the class a puzzle, that seems easy, and everyone gets the wrong answer. It's the predictably irrational and you get to explain by what lights it is irrational. And I think that is valuable. But I, I kind of wanted to take the next step and why that is. Okay, lots of fun to show how, how stupid we are. But that can't be the end of the story. Because who is it that set the benchmarks for rationality, against which we can say humans fall short? Well, it's just other human beings. And unless you will think to say that statisticians and mathematicians and cognitive psychologists and economists are a superior breed of human, we obviously are using abilities that that everyone has. And we need a better way of understanding rationality than just saying that people are irrational that the the Mr. Spock conclusion, it's more what what are the mechanisms that we use to reason? What are their comfort zones? That is, what do they what environments do they evolve to work well in? What is what are the pathologies that distort them, at least by the lights of objective science to the extent that, that that's our gold standard. And I was influenced, of course, by Tversky and Kahneman, but also by by some of their, their their critics and people presenting a somewhat different view, that it wasn't so much that people are irrational, but just that the brain teasers that we tend to give them to demonstrate your rationality, often, we're, we're kind of trick questions. Often they involve assumptions that people will quite reasonably think don't hold. And then a second look shows that with that the conclusion that humans just have a long list of biases and fallacies and fundamental errors, is - it's interesting but only goes so far in understanding human rationality.
Hmm, well, I mean, it is interesting because we're here. We're pretty successful as a lineage. You talk about the San Bushmen of the Kalahari in the book, you know, if humans were so muddled in a rational and I don't know crazy. Maybe you would say that word. Or I could. How did how did we persist for hundreds of 1000s millions of years and spread out across the world? Could you talk a little about the evolutionary context of rationality as you understand it?
Yes, I hear I'm borrowing from an idea that was first articulated by John Tooby and Irven DeVore, and Leda Cosmides. An unacknowledged co author of that that paper that what's what's zoologically unusual about humans is that we occupy the what they call the cognitive niche, that it is a way of prospering that depends on a complex of traits of which I think three are key. One of them is technological know how being able to manipulate the world to our advantage through cognitive models. That is we develop intuitive theories about how physical objects behave, how living things behave, how other humans behave. We use those - that knowledge to play out scenarios in our mind's eye, we can do medical experiments we can see and to be tried to see into the future, where we are unquestionably brainy creatures, both literally in this size of our brains relative to our bodies. And the fact that that's, we live by our wits. And I start the book with examples of San ingenuity, to remind people, they just say, Well, of course, we're rational, we're basically hunter gatherers. Well, yeah, but actually, the hunter gatherers aren't so irrational, they distinguish correlation from causation, they engage in Bayesian reasoning, they infer the presence in age and condition and sex of animals from from remarkably sparse, clues that they leave behind. So there's that and that's what that that's the feature of Homo sapiens, that's really the subject of this book. But in addition, we have language that that makes us pretty weird among animals. And then of course, it was the subject of so in my previous books, particularly "The Language Instinct", not a coincidence, because one of the things that makes language useful is that you've got knowledge to share. If we had nothing to talk about, then it's not so clear what was the big advantage to language would have been in the first place. And know how is something that is a particularly good trade good, because it's information. So if I share it, I don't have to relinquish it myself. It's a non rival good as as economists sometimes say, or as Thomas Jefferson put it, if I light your candle, your candle is lit, but it's not as if mine went out. And knowledge is like that information is like that. Then the third feature, I think, of the cognitive niche is that we are social, we cooperate with non-relatives, again, not so common in the animal kingdom, not unrelated to the first two adaptations, namely, cognitive know how, which gives us a reason to congregate socially to exchange favors, because knowledge is a big favor can be shared at confer a large benefit to someone else at a small cost to oneself, which is the prerequisite to reciprocity, reciprocal altruism, which binds non relatives together. And of course, we wouldn't be sharing information. We wouldn't be using language unless we were social creatures and had a reason to blurt out things to each other. mortal enemies don't talk to before a football game two football coaches don't sit down and have a conversation. Communication itself is a kind of cooperation. So those three things evolved together. And it makes it is the very essence of our species, that we are a brainy smart species. Just saying, here's, here's a Wikipedia page with 200 fallacies. That's what human rationality consists of just it's not quite satisfying.
Yeah, um, you know, what is? I need to ask you then. So rationality so you know, you are, you know, you're a big proponant of evolutionary psychology, you're an evolutionary psychologists this like Swiss Army Knife model. There were these ideas about massive modularity and, you know, domain specificity versus domain general. How do you how do you relate rationality to this evolutionary psychological model of like cognitive specializations? Is it its own specialization? I mean, what would you say?
Well, mass of modularity is a kind of a term of abuse from critics of evolutionary psychology. It's not, I don't consider it to be essential to the to the approach, I think, with more specialization that is that the human brain is not just one big unsupervised learning network to to riff off the title of the show, yeah. And, but that we have we are specialized to reason and to have different emotions and motives in different domains. And I, I do think that our reasoning ability is kind of leveraged off some basic intuitions or mental models or mental modules, if you will, or ways of knowing or multiple intelligences that have different intuitions in different domains. So we reason about artifacts and manmade things in a different way that we reason about living things, which in turn differs from how we reason about inanimate objects. That, and then a lot of abstract intelligence. How do we do physics? How do we play chess? How do we articulate the principles of democracy, all these things that presumably we were not so adapted to do. A lot of it builds either metaphorically or analogically, off existing concepts. And this was the topic of an earlier book, "The Stuff of Thought", where it's pretty hard to find any passage of language that isn't based on some pretty concrete metaphors I have, I have an analysis there of the opening words, the Declaration of Independence, which is about every word, or at least originated in some physical object or physical process. Plus, we have the ability to combine ideas, and combinatorial cognition, the fact that we don't just regurgitate a fixed set of ideas, but we can embed one in another, we can juxtapose them and add them and then chunk them and have them as an ingredient in still bigger structures. The combination of analogy and combinatorics means that with a... starting with probably some finite set of ways of understanding the world, they can explode to allow us to do all these wild and wonderful things that human thinkers can do.
Yeah, yeah. I mean, that makes sense. And I do think, you know, I don't want to say miracle, but like human complexity, our society, our sociality, all these things, in hindsight, this vote for irrationality and you know how we can't think clearly - it's, it seems kind of silly to me. Now, but you know, what, I have some I have some distance between reading all those books, which they're very entertaining, very interesting and entertaining examples. I want to ask you, you talked about critical thinking I think and logic, you have your chapter on logic versus critical thinking. Can you talk about the difference? I think, you know, colloquially, the listeners will probably know, but could you get into it a little bit about how they, you know, compliment each other?
are you talking about logic and critical thinking.
Yeah, as opposed to like, if like, if you can distinguish the two in any way?
Yes. So logic is a formal system that allows us to go from true premises to true conclusions, by certain rules of inference. It's mechanical, you don't barely have to know what the what the words mean, you just know, by looking at truth tables, if P is true, and Q is true, then P or Q is true. So it's P and Q. And by a set of rules like that, you could crank out an indefinite number of true beliefs starting from some true premises. It's different from reasoning, because when you do logic, you're only allowed to pay attention to the the form of propositions, not their actual content. And you're only allowed to use a few of the rules in the system. So all of the... so if I say to you, here, here is a here's a syllogism, tell me whether it's valid or not. All plants are healthy. tobacco is a plant, therefore tobacco is healthy. You know, if you say no, no, that can't be right. Tobacco isn't healthy. Everyone knows that give you a lung cancer and emphysema. That's rational, but it's not logical, because I said, No, no, wait, you just got to forget everything you know, just pay attention to what was stated in the premises and it is a valid syllogism it's valid. It's not sound because it is not true that all plants are healthy - tobacco being the blatant counter example. But if you're doing logic, you don't think that way you don't you have to put aside everything you know. Now in some contexts, that's a very useful thing to do. Because sometimes what you think you know, might be irrelevant or distracting or confusing, or you may have reasons for setting it aside. When we design computers, we want them to be purely mechanical, and we don't want to get bogged down by their lack of common sense. But a human in a social environment with a lifetime of experience. It's perfectly reasonable to not confine yourself to a few if/then rules but rather than to throw in e verything you know, including many things that are probabilistic that nudge you, your confidence up or down, but that falls short of actual logic.
I give an example how often philosophy professors get frustrated when students introduce irrelevant considerations into some of their pristine thought experiments, which are designed just to clarify reasoning. So we know the famous trolley problem. If there are if there's a runaway trolley, the operator has collapsed and it can - it's sets on its course it's going to kill a worker on the tracks, who doesn't see it coming. If you divert it to another track, it will kill five, is it okay to... sorry, I said it backwards - Is it okay to divert it from the track with five workers and deliberately kill one? Now some students when they hear that say, Well, why don't you just shout at the workers to get out of the way? Now, if you're a philosophy professor, it's like, oh, those students, they don't... they missed the point. This is to clarify deontological versus utilitarian reasoning. But of course, in the real world, that's exactly what you would do.
Yeah, yeah. Yeah, that's, that's true. So the next thing I want to talk to you about is you have a chapter on Bayesian reasoning. And I will give, like an example to the listener real quickly about how things have changed when it comes to, you know, Bayesian probability. So when I was in graduate school, my, one of my professors, and you know, this guy's like 50 something now he's not, you know, incredibly old. He said, when he was in graduate school, they had a theory of Bayesian phylogenetics. But they assumed that it would never be implementable because they would never have the computational power to do it. And so Bayesianism, and it has always been there in large, you know, it's old, it's been around for a while, philosophically and in probability, but now it is starting to populate the world around us in a much more concrete way. Bayesian phylogenetics is kind of the gold standard. And that was a shock to him, in terms of he is now you know, pretty big into the field, a field that he was taught would never exist. And so can you talk about why Bayesian thinking is important and what it is and how it's distinguished from the general framework of, of your book, on rationality?
Yeah, you're right. One of the reasons that I had a chapter on what some people might think of is as difficult abstruse theory, it actually is, it's pretty common sensical. But one of the reasons that I had it, in fact, one of the reasons for writing the book is that it's one of Bayesian thinking, it's just one of those tools for thinking that if you, even though, we all are Bayesian in the sense that a lot of we judge evidence when it comes in, in terms of our prior beliefs, and in terms of the commoness of the evidence, and I give examples of Bayesian thinking among the San, but we don't have it as a thing as as an idea that when a problem presents itself in an unusual format, most people don't think Oh, I bet I could apply Bayesian thinking to that because they just don't have the explicit concept of Bayesian thinking even though they do it all the time. It's like the the Voltaire character who's delighted to learn that even speaking prose all his life, we all are Bayesian but if we don't have it as a concept, we may not realize that there are certain contexts and circumstances where we apply it consciously, and we can come to better conclusions. The idea behind Bayes theorem is Bayes rule. It's, it's pretty obvious that is if you imagine that you your degree of credence in a idea, belief, a hypothesis is not black and white, we can think of it as being on a scale from zero, you're sure it's false to one, you're sure it's true. And anything in between. The way you ought to change that credence in response to evidence is you start off with the priors. And that's a term that's escaped from Bayesian reasoning into common parlance in the last decade or so just one more sign of how Bayesian - as you as you note, Bayesian reasoning is becoming more and more influential, and more and more fields, including journalism with the term priors is a Bayesian term, we start off with the priors. That is, what's your degree of belief in it before you even look at the evidence based on everything you know, so far? You multiply that by the - or you scale it - If I use multiply it sounds scarier than it is you adjust it, let's say, yeah, the likelihood that is if the idea is true, how likely is it that you'd see the facts that you're now seeing you divided by the commoness of the evidence that is how common are those experiences across the board whether the idea is true or false? That's Bayesian reasoning. Where, famously people often fall short of Bayesian reasoning is that they don't take the - according to Tversky and Kahneman they neglect the base rate of the mean source of priors. And they just reason by stereotypes. If I give you a description of a student, we'll call her Isabel - And she likes to write sonnets and she spends summers in Italy. And she's considered very impractical and creative, and artistic. What is the probability that she is a an art history major? What is the probability that she is a psychology major? Well, most first reaction is as a no brainer. Of course, she's an art history major. But then when you think they're probably, like, 250, psychology majors for every art history major. So regardless of her traits, or stereotype, you're pretty, you'd be better off going with the odds and say, there's likely a she's a psychology major. Not doing that would be a kind of failure of Bayesian reasoning.
Yeah, yeah. Well, I mean, another, I think, for the listener, a pretty well known and famous one is the issue where you have like really low frequency, you know, low frequency, you know, like, say, test results that are true positives, and then you get a test result, and what's the probability that the person actually has this really low frequency condition, and people are just like, freaking out, like, Oh, my God, I got it, I got a, I got a positive test result, but your base rates really low. So there's a really strong chance of a of a false positive. So this is, this is a practical issue in terms of base rates. But sometimes, there are issues of like updating from your base rate. So I will say, you know, you mentioned COVID-19, in the book, I feel like there are some medical doctors that I knew who would not, and did not update their priors very radically when the pandemic started, because, you know, they'd had to deal with the H1N1 scare, they'd had to deal with the Ebola scare, they had to deal with a lot of scares, and so I understood where their prior was coming from. But they were pretty sticky. And they were not updating pretty late into March. And this is just my personal experience of having to try to countermand the authority of some medical doctors who were telling people that I knew that they shouldn't be worried, because this is just another scare. Now, obviously, they've updated at some point, but, you know, perhaps they should have updated a little earlier.
Right? Well, no, that that's absolutely right. Now, part of the paradox is even though that in the literature on Judgment, and decision making, heuristics and biases that you noted, was the topic of a number of bestsellers. The the generalization that people that psychologists and behavioral economists always make is that people forget the priors, they or they say, forget the base rate. And they're just buffeted around by the last piece of evidence that they see. Now, you just pointed to a case that's the opposite. People will stick to their priors. Yep. And aren't updating as quickly as they should. So that's one of the reasons why just saying people look like base rates, you got to be a little more subtle than that. Because sometimes people don't update when they should. And then in the case of COVID, I actually, without citations, I didn't want to embarrass some people, some some friends, actually, there were some experts in cognition, who at the early days of the pandemic, tried to poopoo it saying, Oh, well, the chance - your chance of dying of COVID are comparable to risks that we commonly assume like driving and swimming in pools, but didn't appreciate that, at the start of the pandemic, you might be at the kind of inflection point of exponential growth, and exponential growth is deeply unintuitive. And there are famous examples like the... that 3am cognitive reflection test, one question of which is, if you've got, lily pads, lily pads on a pond that are doubling every day, at the end of 30 days, the pond is completely covered. on what day is the pond half covered? And the answer is on day 29. But and people you know, kind of get that when you explain it to them. But it isn't that intuitive and blast off of exponential growth is not so intuitive. And the - what I think some of the the - deniers in the early days of pandemic probably weren't intuitively appreciating is Yeah, the death rates pretty low now but with some people coughing on others who then can cough on others, you can get exponential growth that it can zoom to high levels faster that you think.
Yeah, I will say, you know, I was pretty worried pretty early, and I can give My reason is I've had less to do with some... I mean, I don't have a deep knowledge of virology pandemics or epidemiology. It's just the revealed preference of the way the Chinese government behaved in the middle to the end of January of 2020. told me that if this is generalizable, we were in a world of hurt. Now, the one hope that I had, was there was something special about China that made it particularly vulnerable, which, unfortunately, is not correct. It turns out the case fatality rates that were reported in Wuhan in January 2020, have been replicated everywhere. We've had good data. So...
Yes, I mean, the, in that case, when you discount the data coming out by the lack of transparency of China, and that we often really don't know what's going on there.
Yeah, yeah. I mean, this is this is kind of like a Bayesien, you know, Bayesian and thinking experiment where it's, you know, this is not a transparent government, how much should you trust it, etc, etc. And so there's a lot of uncertainty here. And we're trying to make decisions in a world of uncertainty. We're trying to make rational decisions. Right?
Exactly. Which is, yeah, and there's no algorithm for doing it.
Yep. So I want to like, you know, your your book, obviously has a bunch of chapters on different types of reasoning, or rationality and, and all this stuff. But there's also, you know, there's a normative or, you know, you have in your subtitle, "why it matters". And I want to talk to you, I want you to talk about rationality and morality, which is near the end of your book.
Yes, one of the limitations that many people see in rationality is that it can't tell us about moral, it can shed light on moral question, namely, that you you can't get from an 'is' to an 'ought' of a this the argument originated with David Hume and became a staple of 20th century analytic philosophy, that it's just a an error, to use, try to use rationality and logic to determine what's what's right or wrong. And there is an element of truth to that, which is Hume absolutely right, that you can't logically prove to me that I should care more about, you know, genocide of 100 million people than a scratch on my pinky, that I haven't made a logical error. When I say, Well, I just - my pinky hurts. And I care about that. And I don't care about those 100 million people. Well, okay. Yeah. And Hume also noted that you can't... if I were to say that I prefer to be healthy and happy and safe and well fed to being miserable, and in pain and lonely, that's not logical, either. There are brute preferences. That... and that reason always is in service of, he put it the passions, but of our wants, and our needs, which are not themselves logical. Okay. On the other hand, once you acknowledge that there are certain things that I want, like, you know, I'd rather not be in pain, I'd rather be well fed call me irrational, but that just the way I'm put together, once I, I am in conversation with you about anything, such as I know that you could make me miserable. And I'd like you not to, I mean, you could, you could step on my foot, you could beat me up, you can hurt my kids. And so my own well being depends on what you do. Well, you start with those, and you kind of get morality pretty quickly. Namely, I can't insist to you that you treat me well, but at the same time, reserve the right to treat you badly. And hopefully, you'll take me seriously. Because there's nothing inherently logical about the difference between me or you. Anything that I insist on for me, I've got to pretty much have to grant to you. That's the basis of the golden rule and the categorical imperative, and the view from nowhere and the veil of ignorance. And so while it is technically true, that you can't get an ought from an is you get to an ought pretty quickly if you combine if you start with self interest and the sociality, that is, there are some things that I want, I can't deny them to you if I want to be in any kind of discourse with you. So that's a theoretical argument. And then I end the book by saying that not not only is that does that show that reason, is not irrelevant to morality, once you grant the premise of self interest and sociality, but in practice, a lot of the great moral movements began with an argument that that you actually had philosophers or activists, thinkers, who laid out an argument for some barbaric practice of the day like, like sadistic torture is a form of criminal punishment, or slavery or persecuting religious heretics are the absolute right of kings. They showed why those practices were not consistent with other values that that people claim to hold. And often the treatises the manifestos would be published in pamphlets that would go viral would get translated into other languages, they'd be debated in pubs and salons and coffee houses. And then they would often then become the law of the land. So I wouldn't say that all moral movements begin with an argument that all arguments can successfully launch moral movements, but an awful lot of them did.
Mm hmm. Yeah, I mean, that that's, that is very rational and reasonable. So um, you know, I want to say that this is obviously you know, your usual book, it's well written, it's, it's brisk. There's a lot of interesting ideas, and we've just scratched the surface. And so I definitely recommend all the listeners, check out the book, if you like to previous Steven Pinker books, you will like this book. And if you didn't, like previous Steven Pinker books, I don't understand why you're listening to this podcast, but just, you know, that's just being a Bayesian here - But, uh, so I want to, like, talk to something else right now. You know, when I read "The Blank Slate", um, wow, was a while ago now. But I really enjoyed the breadth of the topics that you you touched on. And you did talk about human evolution. And obviously, you know, you're, you're, you're an evolutionary scientist, you know, evolutionary psychologist. So these are priors in your own system of understanding. And we've learned quite a bit since you wrote "The Blank Slate", from Paleogenetics and fossils and whatnot, you know, the admixture and all these things, you know, natural selection going on for, you know, millions , 1000s of years into the present. What, what, if anything, has have the new results? Have they changed your views on things? What's the most surprising to you?
Well, certainly, so the book was published in 2002. And I guess, I number of surprises. We - Neanderthal admixture in modern populations came as a surprise to an awful lot of people. I guess the the evidence for recent adaptation, complicating the idealization that we are we're all hunter gatherers out of time, we probably need some modification. The... I think the growing conclusion has been that you're not going to find the as a basis for adaptations single genes with noticeable effects, then everything is the seems to be the sum of lots and lots of genes with eensy-weensy effects are also rare genes with with big effects, the so called fourth law of behavioral genetics. So I guess, I can't say there's surprises, but those are big, big developments in the last 20 years. Hmm,
Well, so um, you know, so I recently reviewed Page Hardens book, "The Genetic Lottery", which again, like listeners should check it out. It's a interesting book, you might not agree with all of the prescriptions, but I think as a review of the scientific literature and behavioral genetics is great. And, you know, a reader of mine on Twitter pointed out to me that you had been received - reviewed positively in The Nation, in the year 2002, by Steve Berlin Johnson, and I read the review. And, you know, I know Steve's an optimistic guy, things get better. But um, you know, I joked and I'm only half joking, I joke that I should create a Twitter account, waging a campaign against that piece, because it's so dangerous. And I think The Nation would actually pull it off its website, and maybe even get Steve Berlin Johnson in trouble. I feel like the climate in this country on topics that you talked about in "The Blank Slate", which I thought to be frank was pretty definitive that the blank slate was false. I feel like it's gone in reverse. It's, and this is not like, this is not a continuous monotonic process. I feel like something has happened, particularly in the last 10 years. You know, one of the reasons that you were, I mean, I mean, you're you're a prominent public person before this, but in the whole, you know, Larry Summers affair, that wouldn't even be a discussion today, like there would be no discussion. So I feel like, you know, liberals, the left, whatever you want to call them, they've taken a really, really strong turn against some of these ideas about human nature that you were trying to push into the mainstream, rightfully so I think 20 years ago, what do you think about that assertion?
Yeah, it's interesting that a number of the Catholic abuses of the scientific and public intellectual reasoning arena that I documented in "The Blank Slate" in '02 all of the elements of what we now call cancel culture, there were there were threads of it then going back even to the 70s in the reaction to E.O Wilson's, sociobiology But it has, it has exploded, you say the last 10 years, we've probably even more so in the last five years and still more so in the last two years, I think. After, I think a period following "The Blank Slate" in which there was a bit of a window, but it has, I think it has gone in the other direction certainly with with the whole set of movements that are sometimes called critical social justice and wokeism, it has taken a... an extreme form the denial of human nature, particularly when it comes to sex differences. And it is... I did luck out with that Nation review. Because, as I explained in a chapter at "The Blank Slate", there is a kind of historical alignment between the left and the blank slate and the right and somewhat dark vision of human nature. Although I pointed to a number of counter examples, even back then, like Peter Singers book a "Darwinian Left", like Noam Chomsky, like some of the behavioral economists, who use research on human nature as a justification for interventions in the economy. But the that alignment has, has reasserted itself, and a lot of the canceled culture that existed prior to '02 has really exploded since.
Yeah, I mean, I feel like you know, we were talking about political correctness in the 80s, late 80s, and 1990s. And it was little islands in academia, and now it's exploded to the whole of society. So, you know, Steve Berlin Johnson review talks about sex differences, and how, you know, that, you know, opposition to sex differences, and social constructionism is basically going to be a sign that you're like a creationist or a flat earther. And, I mean, I've literally laughed as I read the review, because it was unfortunately, so wrong. And you know,
So wrong in terms of its predictions. It's intalectual environment.
Yeah I mean mean, he just was anticipating that, you know, who, yeah, what reasonable person would reject sex? You know, and now you have like, what's happening to Carol Hooven with her book, "T", which, you know, that's great book. And I know, I think you blurb the book. And
Yeah, so she's a former student of mine. Yeah. Yeah, that's terrific book.
It's a great book. I've read it. And - but as I was reading it, so you know, there are articles that talk about how testosterone is not important. And I'm a geneticist, okay? Like I'm focused on human population genetics and other things. I can't like, immerse myself in the literature of every field. I assumed, frankly, that those articles in those books were false, because like, I have strong priors, right? I'm reading Carol's book, like, it was like, okay, she just deconstructed and reviewed the literature of like how testosterone matters and how there's a basically, let's be honest, like artifactual manipulation of like pooling the data sets in certain ways and whatnot. And it's ridiculous that here we are, in 2021, she has to write a book, where she has to, like debunk things that are prima facie, just, you know, okay, this doesn't make any sense to anyone. But, um, you know, you wrote a book about the decline of violence. And also, you know, you wrote "Enlightenment Now", recently, you know, I think these are optimistic books. And there is a reason for optimism, I think you're a big supporter of our world in data, you know, the massive decline in poverty. I mean, since you wrote "Blank Slate", China has become an upper middle income nation. A lot of Chinese are, you know, that were poor are no longer poor, and that's good. On the other hand, we have no, I don't want to soft pedal, the Uyghur, the Uyghur, you know, issues in western China, but so on the aggregate, I think that that's a defensible argument still, but to be entirely frank, I feel like we're kind of in a darker moment in our society. And in terms of the intellectual traditions of both of us, I feel that we come out of and respect and view as the culmination of the Western enlightenment. I feel like we're kind of in a dark moment right now, like, do you have anything to say to make me feel more hopeful?
Yes, well, we did go through phases like that earlier and the 60s and 70s were another phase of - where a lot of intellectuals proudly declared that they were Marxists. That the as you know, people like E.O Wilson and Arthur Jensen and Hans Eysenck and Tom Bouchard were sometimes assaulted... Michael Bailey. So it is a - we have gone through moments of, of tremendous intolerance. They, I don't want to predict that we're going to reason our way out of them. But there are younger people who are getting sick of being intimidated out of speaking their minds out of being told what to think. There are there is a push back in a number of organizations I'm sure you're familiar with like, heterodox, like Fire, like Fair Light and Academic Freedom Alliance like Free Speech Union like Counterweight. And it says... A lot of it - a lot of this, this repression comes from bullying campaigns by minorities and intimidated administrators who just don't want to make trouble. And so they acquiesce to the bullies. There is at least an opening for the reasonable I don't want to say necessarily majority, but probably are a majority to - to start pushing back.
Well, you know, I want to hear that. I want to feel that, because the last five years last couple of years has been pretty dispiriting to see what's been happening in this intellectual climate of the West that I think we both love. I want to ask you about some other things. If you have some time, some the replication the replication crisis has happened since you wrote "The Blank Slate". And so I was wondering, like, what do you think about the replication crisis? Now that it's, it's, you know, I mean, it's kind of past its high tide in terms of I think people have integrated it into their thinking. A lot of the behavioral economics and the heuristics and biases literature, frankly, is coming under serious scrutiny right now, as we record, based on some of the stuff related to the replication crisis, I think it's going to hit medicine. I think it's going to hit biomedicine to be entirely Frank. And I think that's going to be a much bigger deal. Because, yes, there's some serious money on the line, but
Right. Well and it was from medicine that one of the first bellwethers, the replication crisis came that famous article by John Juanettes say yes to the publish, most published research results are false and that paper referred specifically to the medical literature Back then, I talked about some of the cognitive shortcomings that led to replicability failures in the new book in "Rationality" one of it being a failure to distinguish between prior and post hoc probability - the Texas sharpshooter fallacy were referring to the guy who shoots a bullet into the side of a barn and then pay up to target around the hole. And a lot of scientific practices haven't properly safeguarded against the Texas sharpshooter fallacy. In particular, the way we use this concept of statistical significance, which people, including editors of science journals, some of our best science journalists repeatedly misunderstand as a Bayesien concept that is, when a result is statistically significant. They say Oh, that means that it's, there's only a 5% chance that it's false. Now, that is just a mathematical error. The statistical significance level, is the likelihood is not a posterior probability. That is, if the hypothesis were false, what are the chances that you get the data that you get? Which is not the same as the probability that the hypothesis is false? Yeah, in fact, and as we know, if you are studying something completely bogus, say there's a great XKCD cartoon where they test 20 different flavors of jelly bean to see if any of them give you acne. And they find that the green jelly beans are associated with acne at a significance level of p is less than point oh five, ie one out of 20. ie exactly what you would expect. If jellybeans don't cause acne, then you publish the result that says that green jelly beans are associated with acne p is less than .05, put the other 19 studies in the file drawer. And that's a recipe for for artifact - for a replication crisis.
Yeah, yeah. So ...
Also just a failure of Bayesian and applying proper Bayesian reasoning to science and some of the perverse incentives that you want etus pointed out, namely, if you're a Bayesian scientists, you evaluate every new finding in terms of your priors, what is the entire body of evidence up till now lead us to think is plausible or implausible? And if a result goes against everything we believe you maybe everything we believe is false, but it's just as likely - In fact, it's more likely that the data are false. And that the the premium bet that science places and the even greater premium that science journalism places on the revolutionary finding the surprising finding the counterintuitive finding the Kuhnian scientific revolution, the upstart who proves that his elders were full of baloney, all of that selects for error, because it throws out base rates and it favors the just those results that are least likely to be true. And so the all the flukes get an inappropriate hearing. So those are some of the the I think the reasons behind it and the least in psychology, where it all hit the fan was that preposterous study by In the early 2000s, claiming to demonstrate pre cognition that is ESP in college students, Darryl Ben was published in one of the prestigious journals. And if one was a Bayesian one would say, Well, if he got statistical significance, then he's probably one of the one out of the 20 people who will get statistical significance when there's nothing going on. That's what statistical significance means. Why do we suspect that? Well, everything we know about the laws of physics suggests that there's no such thing as pre cognition. If you have a study that claims to find it, there's a pretty good bet that it's that it's one of those studies that turned up ... differences by chance, but because somehow, within social psychology, it wasn't considered to be cricket to bring up the laws of physics and plausibility and consistency with our knowledge, it got a pass. And anyway, I'm sorry, I'm going on because I think the replicability crisis happened. It's all to the good that we're, we're much more aware of it that, that we're have bad habits that, you know, the irony is when I was an undergraduate, the 70s, my stats press Professor talked about thesis as errors, but it just did not affect the way we went ahead and did science.
Mm hmm. Yeah, I mean, there's science is a cultural social process, right? So you know, we've been talking for a while, so I want to, you know, let you go. But um, you know, we talked about "Rationality", your new book, you know, we talked about science and, and you know, what's happened in our culture some serious heavy topics. So, last fall, I was on social media on Twitter as I am a fair amount. And um, yeah, yeah..
Yeah I follow you
yeah, yeah, which you do, but you show up on my timeline in a very, very surprising way. Some people who don't know who you are, are making fun of this dancing Boomer.
Um, that would be me. Yeah.
So I'm having to like explain to like random people who you are, which I you know, I mean, like to be frank, Steven, you You're pretty famous as a scientist, but you're still a famous scientist. You're scientist famous, right? And so, you know, now you're famous as a dancy meme. And, you know, some people are kind of mean about it. Some people just start like laughing about it. There's all sorts of reactions. You're just you're a phenomenon for like a week. Like, you know, my wife is like, still seeing the Steven Pinker dancing like he's still on my timeline. He's just people are just, yeah, they're still read, you're still being rediscovered, you know, like, it'd be - what was your reaction to becoming a meme?
You know, I don't think I was aware that I would become a meme. This was - what you're referring to is that when the election was more or less called for Biden, after those few weeks of counting a few days of counting votes. My wife Rebecca Goldstein, and I broke out into a dance to the tune of Ella Fitzgerald singing, the "Wicked Witch is Dead". And we decided to set up the cell phone and film a little dance and I did not realize that it would go viral. And I can't claim that I was a particularly graceful or or lithe dancer, I think. I think Rebecca is pretty good. But but but but not me. So I was I was certainly setting myself by filming that and putting it on my Twitter feed.
Right. So someone was, you know, you're pretty well known for your hair. I explained that you were a well known evolutionary psychologist. And they're like 'I thought scientists cut their hair...' and I was like 'you're discovering the world of Steven Pinker'. Like the hair has been a talking point for the whole time that I've known of you.
Actually I was the type specimen the the the the first exemplar the luxuriant flowing hair club for scientists.
Yes. Yes. Yeah. Someone someone recently said that. I think they saw you in Berkeley. And they, they knew that it was you. I mean, you're just your hair. Okay. Your hair is distinctive. It's, it's kind of like some sort of green beard. I don't know. Anyhow, so the book is "Rationality: what it is, why it seems scarce, and why it matters". You know, just go out and get it guys. It's really great. Steven's older books are also great. You know, I love Like I said, I mentioned "The Language Instinct", I think. I think "The Blank Slate" has influenced me the most but I have to be honest, like, "The Language Instinct" I read in probably like two sittings back in the 1990s when I was just, you know, you know, it's just it's not my field. But it's it's really a fascinating book. And it's been great to talk to you, Steve.
Thanks so much Razib thanks for having me on and keep up the great work.