Richard Haier: IQ Tests, Human Intelligence, and Group Differences | Lex Fridman Podcast #302
let me ask you to this question whether it's bell curve or any research on race differences can that be used to increase the amount of racism in the world can that be used to increase the amount of hate in the world my sense is there is such enormous reservoirs of hate and racism that have nothing to do with scientific knowledge of the data that speak against that that no i don't i don't want to give racist groups of veto power over what scientists study the following is a conversation with richard heyer on the science of human intelligence this is a highly controversial topic but a critically important one for understanding the human mind i hope you will join me in not shying away from difficult topics like this and instead let us try to navigate it with empathy rigor and grace if you're watching this on video now i should mention that i'm recording this introduction in an undisclosed location somewhere in the world i'm safe and happy and life is beautiful this is a lex friedman podcast to support it please check out our sponsors in the description and now dear friends here's richard higher what are the measures of human intelligence and how do we measure it everybody has an idea of what they mean by intelligence in the in the vernacular what i mean by intelligence is just being smart how well you reason how well you figure things out what you do when you don't know what to do those are just kind of everyday common sense definitions of how people use the word intelligence if you want to do research on intelligence measuring something that you can study scientifically is a little trickier and what almost all researchers who study intelligence use is the concept called the g factor general intelligence and that is what is common that is a mental ability that is common to virtually all tests of mental abilities what's the origin of the term g factor by the way it's such a funny word for such a fundamental human thing the general factor i really started with charles spearman and he noticed this is like a boy more than a hundred years ago uh he noticed that when you tested people with different tests all the tests were correlated positively and so he was looking at student exams and things and he invented the correlation coefficient essentially and he when he used it to look at student performance on various topics he found they all the scores were correlated with each other and they were all positive correlations so he inferred from this that there must be some common factor that was irrespective of the content of the test and positive correlation means if you do well on on the first test you're likely to do well in the second test and presumably that holds for tests across even disciplines so not within subject but across subjects so that's where the general comes in some something about general intelligence so when you were talking about measuring intelligence and and trying to figure out something difficult about this world and how to solve the puzzles of this world that means generally speaking not some specific tests but across all tests absolutely right and people get hung up on this uh because they said well what about the ability to do x isn't that independent and they said i know somebody who's very good at this but not so good at this other thing yeah and so there are a lot of examples like that but it's a general tendency so exceptions really don't disprove you know your your everyday experience is not the same as what the data actually show and your everyday experience when you say oh i know someone who's good at x but not so good at why that doesn't contradict the statement of about a he's not so good but he's not the opposite he's not a it's not a negative correlation okay so we're not with our anecdotal data i know a guy is really good at solving some kind of visual thing that's not sufficient for us to understand actually the depths of that person's intelligence so how this idea of g factor how much evidence is there how strong you know given across the decades that this idea has been around how much has it been held up that there is a universal uh sort of horsepower of intelligence that's underneath all of it all the different tests we do to try to get to this thing uh in in the depths of the human mind that's a that's a universal stable measure of a person's intelligence you used a couple of words in there yeah stable and we have to be precise with words well hoping we can get away with being poetic we can there's a lot about research in general not just intelligence research that is poetic science has a phonetic aspect to it and good scientists are are very intuitive they're not just hey these are the numbers you have to kind of step back and see the big picture when it comes to intelligence research you asked how well has this general concept held up and i think i can say without fear of being empirically contradicted that it is the most replicated finding in all of psychology now some cynics may say well big deal psychology we all know there's a replication crisis in psychology and a lot of this stuff doesn't replicate that's all true there is no replication crisis when it comes to studying the the existence of this general factor let me tell you some things about it it is it it looks like it's universal in uh that you find it in all cultures the way you find it let's step back one one step the way you find it is to give a battery of mental tests what battery you choose take a battery of any mental test you want give it to a large number of diverse people and you will be able to extract statistically the comment the commonality among all those tests it's done by a technique called factor analysis you people uh think that's that this may be a statistical artifact of some kind it is not a statistical artifact what is factor analysis factor analysis is a way of looking at a big set of data and look at the correlation among the different test scores and then find empirically the clusters of scores that go together and there are different factors so if you have a bunch of mental tests there may be a verbal factor there may be a numerical factor there may be a visual spatial factor but those factors have variants in common with each other and that is the common uh that's what's common among all the tests and that's what gets labeled the g factor so if you give a diverse battery of mental tests and you extract a g factor from it that factor usually accounts for around half of the variance it's the single biggest factor but it's not the only factor but it is the most reliable it is the most stable and it seems to be very much influenced by genetics it's very hard to change the g factor with training or drugs or anything else don't know how to increase the g factor okay you said a lot of really interesting things there so first i mean just to get people used to in case they're not familiar with this idea g factor is what we mean so often there's a uh this term used iq which is the way i iq is used they really mean g factor in regular conversation the way cause we what we mean by iq we mean intelligence and what we mean by intelligence we mean general intelligence and general intelligence in the human mind from a psychology from a serious rigorous scientific perspective actually means g factor so g factor equals intelligence just in this conversation to define terms okay so so there's this stable thing called g factor you said now factor you said factor many times means a measure that's a potential could be reduced to a single number across the different factors you mentioned and uh what you said it accounts for half half ish accounts for half ish of what of variance across the different set of tests so if you're if you do for some reason well on some set of tests what does that mean so that that means there's some unique capabilities outside of the g factor that might account for that and what are those what else is there besides the raw horsepower the engine inside your mind that generates intelligence there are test taking skills there are specific abilities someone might be particularly good uh at mathematical things mathematical concepts even simple arithmetic people are some people are much better than others you might know people who can memorize and short-term memory is another uh component of this uh short-term memory is one of the cognitive processes that's most highly correlated with the g factor so so all those things like memory uh taste test taking skills account for variability across the the test performances but you so you can you can run but you can't hide from the thing that god gave you the genetics so that g factor science says that g factor is there each one of us have each one of us has a g factor oh boy some have more than others i'm getting uncomfortable already well iq is a score and i q an iq score is a very good estimate of the g factor you can't measure g directly there's no direct measure you estimate it from these statistical techniques but an iq score is a good estimate why because a standard iq test is a battery of different mental abilities you combined it into one score and that score is highly correlated with the g factor even if you get better scores on some subtest than others because again it's what's common to all these mental abilities so that a good iq test and i'll ask you about that but a good iq test tries to compress down that battery of tests like tries to get a nice battery the nice selection of variable tests into one test and so in that way it sneaks up to this gfa and that's another interesting thing about g factor now you give first of all you have a great book on the neuroscience of intelligence you have a great course which is when i first learned you're a great teacher let me just thank you uh you your course at the teaching company i hope i'm saying that correctly the intelligent brain the intelligent brain is when i first heard about this g factor this mysterious thing that lurks in the darkness that we cannot quite shine at light on we're trying to sneak up on so the fact that there's this measure stable measure of intelligence we can't measure directly but we can come up with a battery test or one test that includes a battery of um variable type of questions that can reliably or attempt to estimate in a stable way that g factor that's a fascinating idea so for me as an ai person it's fascinating it's fascinating there's something stable like that about the human mind especially if it's grounded in genetics it's both fascinating that as a researcher of the human mind and all the human [Music] psychological sociological ethical questions that start arising it makes me uncomfortable but truth can be uncomfortable you know i i get that a lot about being uncomfortable talking about this uh let me go back and just say one more empirical thing uh it doesn't matter which battery of tests you use so there are countless tests you can take any 12 of them at random extract a g factor and another 12 at random and extracted g factor and those g factors will be highly correlated like over 0.9 with each other that's very so it is a ubiquitous it doesn't depend on the content of the test is what i'm trying to say yes it is general among all those tests of mental ability and tests of mental you know mental abilities include things like geez uh playing poker your skill at poker is not unrelated to g your skill at anything that requires reasoning and thinking anything from spelling arithmetic more complex things uh this concept is ubiquitous and when you do batteries of tests in different cultures you get the same thing so this says something interesting about the human mind that is a computer is designed to be general so that means you can [Music] so it's not it's not easily made specialized meaning if you're going to be good at one thing miyamoto musashi has this quote he's an ancient warrior uh famous for the book of five rings in the martial arts world and the quote goes if you know the way broadly you will see it in everything meaning if you do one thing is going to generalize to everything and that that's an interesting thing about the human mind so that that's what the g factor reveals okay so what's the difference if you can elaborate a little bit further between iq and g factor just because it's a source of confusion for people and iq is is a score people use the word iq to mean intelligence but iq has a more technical meaning for people who work in the field and i it's an iq score score on a test that estimates the g factor and the g factor is what's common among all these tests of mental ability so if you think about it's not a venn diagram but um i guess you could make a venn diagram out of it but the g factor would be really at the core what's what's common to everything and i what iq scores do is they allow a rank order of people on the score and this is what makes people uncomfortable this is where there's a lot of controversy about whether iq tests are biased toward any one group or another and a lot of the the answers to these questions are very clear but they also have a technical aspect of it that's not so easy to to explain well we'll talk about the fascinating and the difficult things about all of this but uh so by the way when you say rank order that means you get a number and that means one person you can now compare like uh you could say that this other person is more intelligent than me well what you can say is iq scores are interpreted really as percentiles so that uh if you have an iq of 140 and somebody else has 70 the metric is such that you cannot say the person with an iq of 140 is twice as smart as a person with an iq of that would require a ratio scale with an absolute zero now you may think you know people with zero intelligence but in fact there is no absolute zero on on an iq scale it's relative to other people so relative to other people somebody with an iq score of 140 is in the upper less than one percent whereas somebody with an iq of 70 is two standard deviations below the mean that that's that's a different percentile so it's similar to like in chess you have an elo rating that's designed to rank order people uh so you can't say it's twice one person if if your yield rating is twice another person i don't think you're twice as good at chess it's not stable in that way but because it's very difficult to do these kinds of comparisons but uh so what can we say about the number itself is that stable across tests and so on or no there are a number of statistical properties of any test they're called psychometric properties you have validity you have reliability reliability there are many different kinds of reliability they all essentially measure stability and iq tests are stable within an individual there are some longitudinal studies where children were measured at age 11 and again when they were 70 years old and the two iq scores are highly correlated with each other this comes from a fascinating study from scotland uh in the 1930s some researchers decided to get an iq test on every single child age 11 in the whole country and they did and those records were discovered in an old storeroom at the university of edinburgh by a friend of mine ian deary who found the records digitized them and has done a lot of research on the people who are still alive today from that original study including brain imaging research by the way really it's a fascinating group of of people who are who were studied not to get ahead of the story but one of the most interesting things they found is a very strong relationship between iq measured at age 11 and mortality so that you know in the 70 years later they looked at the survival rates and they could get death records from everybody and scotland has universal health care for everybody and it turned out if you divide people by their age 11 iq score into quartiles and then look at how many people are alive 70 years later the i know this is in the book they have the graph in the book but there are essentially twice as many people alive in the highest iq quartile than in the lowest iq quartile it's true in men and women um interesting so it makes a big difference now why this is the case is not so clear since everyone had access to health care well there's a lot and we'll talk about it you know just the sentences you used now could be explained by nature or nurture we don't know now there's a lot of science that starts to then dig in and investigate that question but let me linger on the iq test how are the tests designed iq tests designed how do they work maybe some examples for people who are not aware what what makes a good iq test question that sneaks up on this on this g factor measure well your question is interesting because you want me to give examples of items that make good items and what makes a good item is not so much its content but its empirical relationship to the total score that turns out to be valid by other means yeah so for example let me give you an odd example from personality testing nice so there's a personality test called the minnesota multiphasic personality inventory mmpi been around for decades i've heard about this test recently because of the johnny depp and uh amber heard trial i don't know if you've been paying attention to that but they have not been paying attention they had psychologists on the st on the stand and they were talking apparently those psychologists did uh again i'm learning so much from this trial they have uh they did different at the battery of tests to uh diagnose personality disorders apparently there's that systematic way of doing so and the minnesota one is one of the ones that there's the most science on there's a lot of great papers which were all continuously cited on the stand which is fascinating to watch sorry a little bit of attention okay i mean this is interesting because you're right it's been around for decades there's a lot of scientific research on the psychometric properties of the test including what it predicts with respect to different categories of personality disorder but what i want to mention is the content of the items on that test all of the items are essentially true false items true or false i prefer a shower to a bath true or false i think lincoln was a better president than washington what have all these what does that have to do and the point is the content of these items nobody knows why these items in aggregate predict anything but empirically they do it's a technique of of choosing items for a test that is called dust bowl empiricism that the content doesn't matter but there it for some reason when you get a criterion group of people with this disorder and you compare them to people without that disorder these are the items that distinguish irrespective of content it's a hard concept to grasp well uh first of all it's fascinating but uh from uh because i i i consider myself part psychologist because i love human robot interaction and that's a problem half of that problem is a psychology problem because there's a human so designing these tests to get at the questions is the fascinating part like how do you get to uh like what does dust bowl empiricism refer to does it refer to the final result yeah so it's the test is dust bowl empiricism but how do you arrive at the battery of questions i presume uh one of the things now again i'm going to the excellent testimony in that trial the explanation also they explain the tests uh that a bunch of the questions are kind of make you forget that you're taking a test like it makes it very difficult for you to somehow figure out what what uh you're supposed to answer yes it's called social desirability but we're getting a little far afield because i only wanted to give that example of dust bowl empiricism when we talk about the items on an iq test many of those items in the dust bowl and piercing method have no face validity in other words they don't look like they measure anything yes whereas most intelligence tests the items actually look like they're measuring some mental ability so here's here's one so you were bringing that up as an example as what it is not yes got it okay so i don't want to go too far afield on it well too far afield is actually one of the names of this podcast so uh i should mention that far afield far field uh yeah so anyway sorry so so they feel the questions look like they they pass the face validity test and some more than others and so for example let me give you a couple of things here if i one of the subtests on a standard iq test is general information let me just think a little bit because i don't want to give you the actual item but if i said how far is it between washington dc and miami florida within 500 miles plus or minus well you know it's not a fact most people memorize but you can you know something about geography you say well i flew there once i know planes fly for 500 miles you know you can get you can kind of make an estimate but it's also seems like it would be very cultural um you know so there's that kind of general information then there's vocabulary test what does uh regatta mean and i choose that word because that word was removed from the iq test because people complained that disadvantaged people would not know that word just from their everyday life okay here's another example from a different kind of subtest on what's regatta by the way a regatta is a um i think this advantage is a sailing competition a competition with boats not necessarily sailing but the competition yep yep okay i'm proudly disadvantaged in that way okay excellent so that was removed okay what you were saying okay so now here's a here's another subtest i'm going to repeat a string of numbers and when i'm done i want you to repeat them back to me ready okay 7 four two eight one six that's way too many seven four two eight one six okay you get the idea now the actual test starts with a smaller number you know like two numbers and then it is people get it right you keep going adding to the string of numbers until they can't do it anymore okay but now try this i'm going to re i'm going to say some numbers and when i'm done i want you to repeat them to me backwards i quit okay now so i gave you some examples of the kind of items on an iq test general information um i can't even remember all general information vocabulary digits span forward and digit span backward well you said i can't even remember that that's a good question for me uh what does memory have to do with you well that's all that's that's all that's okay all right so let's let's let's just talk about these examples now some of those items seem very cultural and others seem less cultural which ones do you think scores on which subtest are most highly correlated with the g factor well the d2 advances less cultural well it turns out vocabulary is highly correlated and it turns out that digits span backwards is highly correlated how do you how do you figure now you have decades of research to answer the question how do you figure right so no now there's like good research that gives you intuition about what kind of questions get at it just like uh there's something i've done i've actually used for research to send me a autonomous vehicle like whether humans are paying attention there's a body of literature that does like end back tests for example we have to um put workload on the brain to do recall memory recall and that helps you kind of put some work onto the brain while the person is doing some other tasks and this does some interesting research with that but that's loading the memory so there's like research around stably what that means about the human mind and here you're saying recall backwards is a good predictor the transformation yeah so you have to so you have to do some some like you have to load that into your brain and not just remember it but do something with it right here's another example of a different kind of test called the hick paradigm and it's not verbal at all it's a little box and there are a series of lights arranged in a semi-circle at the top of the box and then there's a home button that you press and when one of the lights goes on there's a button next to each of those lights you take your finger off the home button and you just press the button next to the light that goes on and so it's a very simple reaction time light goes on as quick as you can you press the button and you get a reaction time from the moment you lift your finger off the button when you press the button with where the light is that reaction time doesn't really correlate with iq very much but if you change the instructions and you say three lights are going to come on simultaneously i want you to press the button next to the light that's furthest from the other two so maybe lights one and two go on and and light six goes on simultaneously you take your finger off and you would press the button by light six that's that reaction time to a more complex task it's not really hard almost everybody gets it all right but the your reaction time to that is highly correlated with the g factor this is fascinating so reaction time so there's a temporal aspect to this so it's what what role crossing it's the speed of processing is this also true for ones that take longer like 5 10 30 seconds is time part of the measure with something yes yes and that is why some of the best iq tests have a time limit because if you have no time limit people can do better yeah but it doesn't it doesn't distinguish among people that well so that adding the time element is important so speed of information processing turn and reaction time is a measure of speed of information processing turns out to be related to the g factor but the g factor only accounts for maybe half or some amount on the test performance for example i get a pretty bad test anxiety like i was never i mean i just don't enjoy tests i enjoy going back into my cave and working like i've always enjoyed homework way more than tests uh no matter how hard the homework is because i can go back to the cave and hide away and think deeply there's something about being watched and having a time limit that really makes me anxious and i could just see the mind not operating optimally at all but you're saying underneath there there's still a g factor there's the question no question boy and if you get anxious taking a test many people say oh i didn't do well because i'm anxious yeah you know i hear that a lot yeah well fine if you're really anxious during the test the score will be a bad estimate of your g factor yeah it doesn't mean the g factor isn't there that's right and by the way standardized tests like the sat they're essentially intelligence tests they are highly g-loaded now the the people who make the s.a.t don't want to mention that for obviously they have enough trouble justifying standardized testing but to call it an intelligence test is really beyond the pale but in fact it's so highly correlated because it's a reasoning test sat is a reasoning test a verbal reasoning mathematical reasoning yeah and if it's a reasoning test it has to be related to to g but if people go in and take a standardized test whether it's an iq test or the sat and they happen to be sick that day with 102 fever the score is not going to be a good estimate of their g if they retake the test when they're not anxious or less anxious or don't have a fever the score will go up and that will be a better estimate but you can't say their g factor increased between the two tests well it's interesting so the question is how wide of a battery of tests is required to estimate the g factor well because i'll give you as my personal example i took the sat and i think it was called the act where i was too also i took sat many times every single time i got perfect on math and verbal the time limit on the verbal made me very anxious i did not i mean part of it i didn't speak english very well but honestly it was like you're supposed to remember stuff and like i was so anxious and like as i'm reading i'm sweating i can't you know that like um that feeling you have when you're reading a book and you you just read a page and you know nothing about what you've read because you zoned out that's the same feeling of like i can't i have to you're like nope read and understand and that anxieties like and you start seeing like the typography versus the content of the words like that was i i don't it's interesting because um i know that what they're measuring i could see being correlated with something but that anxiety or some aspect of the performance um sure plays a plays a factor and i wonder how you sneak up in a stable way i mean this is a broader discussion about that's like uh standardized testing how you sneak up how you get at the fact that i'm super anxious and still nevertheless measure some aspect of my intelligence i wonder i don't i don't know i don't know if you can say it to that that time limit sure is a pain well let me say this there are two ways to approach the very real problem that you say that some people just get anxious or not good test takers by the way part of part of testing is you know the answer you can figure out the answer or you can't right if you don't know the answer there are many reasons you don't know the answer at that particular moment you may have learned it once and forgotten it you may it may be on the tip of your tongue and you just can't get it because you're anxious about the time limit you may never have learned it you may never you you may have been exposed to it but it was too complicated and you couldn't learn it i mean there are all kinds of reasons here but for an individual to interpret your scores as an individual whoever is interpreting the score has to take into account various things that would affect your individual score and that's why decisions about college admission or anything else where tests are used are hardly ever the only criterion to make a decision and i think people are a college admission is letting go of that very much oh yes there yeah but what does that even mean because um is it possible to design standardized tests that do get that are useful to college admissions well they already exist the sat is highly correlated with many aspects of success at college here's the problem so maybe you could speak to this the correlation across the population versus individuals so you know our criminal justice system is designed to make sure uh well it's it's it's still there's tragic cases where innocent people go go go to jail but you try to avoid that in the same uh way with testing it just it would suck for an sat to miss genius yes and it it's possible but it's statistically unlikely so the so it really comes down to yeah do which piece of information maximizes your decision making ability so if you just use high school grades it's okay but you will miss some people who just don't do well in high school but who are actually pretty smart smart enough to be bored silly in high school and they don't care and they their high school gpa isn't that good so you will miss them in the same sense that somebody who could be very able and ready for college just doesn't do well on their s.a.t this is why you make decisions with of taking in a variety of in information the other thing i wanted to say you know we talked about when you make a decision for an individual statistically for groups there are many people who have a disparity between their math score and their verbal score that disparity or the other way around that disparity is called tilt the score is tilted one way or the other and that tilt has been studied empirically to see what that predicts and in fact you can't make predictions about about college success uh based on on tilt and mathematics is a good example there are many people especially non-native speakers of english who come to this country take the sats do very well on the math and not so well on the verbal well if they're applying to a math program the professors there who are making the decision or the admissions officers don't wait so much to score on verbal especially if it's a non-native speaker well so yeah you have to try to in the admission process bring in the context but non-native isn't really the problem i mean that was part of the problem for me but it's the the anxiety was which it's interesting it's interesting um oh boy reducing yourself down to numbers but it's still true it's still the truth well it's a it's a painful that same anxiety that led me to be um to struggle with the sat uh verbal tests is still within within me in all ways of life so maybe that's not anxiety maybe that's something um you know like personality is also pretty stable personality is stable personality uh does impact the way you navigate life yeah uh there's no question yeah and and we should say that g factor in intelligence is not just about some kind of um number on a paper it also has to do with how you navigate life how um easy life is for you in this very complicated world so personality is all tied into that in some in some some deep fundamental way but now you've hit the key point about why we even want to study intelligence and personality i think to a lesser extent but that's my interest is more on intelligence i went to graduate school and wanted to study personality but that's kind of another story how i got kind of shifted from personality research over to intelligence research because it's not just a number intelligence is not just an iq score it's not just an sat score it's what those numbers reflect about your ability to navigate everyday life it has been said that life is one long intelligence test [Laughter] and who can't relate to that and if you doubt see another problem here is a lot of critics of intelligence research intelligence testing tend to be academics who by and large are pretty smart people and pretty smart people by and large have enormous difficulty understanding what the world is like for people with iqs of 80 or 75 it is a completely different everyday experience even iq scores of 85 90 you know there's a popular television program judge judy where judge judy deals with everyday people with everyday problems and you can see the full range of problem-solving ability demonstrated there and sometimes she does it for laughs but it really isn't funny because people who who are are there are people who are very limited in their life navigation let alone success by having by by not having good reasoning skills which cannot be taught we know this by the way because there are many efforts you know the united states military which excels at training people i mean i don't know that there's a better organization in the world for training diverse people and they won't take people with iqs under i think 83 is the cut off because they have found you they are unable to train people with lower iqs to do jobs in the military so one of the things that g factor has to do with his learning absolutely some people learn faster than others some people learn more than others now faster by the way is not necessarily better as long as you get to the same place eventually but you know there are professional schools that want students who can learn the fastest because they can learn more or learn deeper or all kinds of of ideas about why you select people with the highest scores and there's nothing funnier by the way to listen to a bunch of academics complain about the concept of intelligence and intelligence testing and then you go to a faculty meeting where they're discussing who to hire among the applicants and all they talk about is how smart the person is we'll get to that we'll sneak up to that in different ways but there's something about reducing a person to a number that in part is grounded to the person's genetics that makes people very uncomfortable but nobody does that nobody in the field actually does that that is a that is a worry that is a worry like um well i don't want to call it a conspiracy theory i mean it's a legitimate worry but it just doesn't it just doesn't happen now i had a professor in graduate school who was the only person i ever knew who considered the students only by their their test scores yes and later in his life he kind of backed off that but um well let me ask you this so we'll jump around i'll come back to the book i tend to uh i've had like political discussions with people and um actually uh my friend michael malus he's uh he's an anarchist i disagree with him on basically everything except um the fact that love is a beautiful thing in this world and he says this test about left versus right whatever it doesn't matter what the test is but um he believes the question is do you believe that some people are better than others the question is uh ambiguous do you believe some people are better than others and to me sort of the immediate answer is no it's a poetic question it's ambiguous question right like uh you know people want to maybe the temptation to ask better what better like sports so on no uh to me i stand with the sort of defining documents of this country which is all men are created equal there's a basic humanity and there's something about tests of intelligence just knowing that some people are different like the science of intelligence that shows that some people are genetically in some stable way across a lifetime have a greater intelligence than others makes people feel like some people are better than others and that makes them very uncomfortable and i maybe you can speak to that like the fact that some people are more intelligent than others in a way that's um cannot be compensated through education through anything you do in life um what do we do with that okay there's a lot there we haven't really talked about the genetics of it yet but you are correct uh in that it is my interpretation of of the data that genetics has a very important influence on the g factor and this is controversial we can talk about it but if you think that genetics the genes are deterministic are always deterministic that leads to kind of the worry that you expressed but we know now in the 21st century that many genes are not deterministic that are probabilistic meaning they their their uh gene expression can be uh influenced uh now whether they're influenced only by other biological variables or other genetic variables or environmental or cultural variables that's where the controversy comes in and we can come we can discuss that in more detail if you like but to go to the question about better people better there's zero evidence that smart people are better with respect to important aspects of life like honesty even likability i'm sure you know many very intelligent people who are not terribly likable or terribly kind or terribly honest is there something to be said so one of the things i've recently re-read for the second time i guess that's what the word reread means the rise and fall of the third reich uh which is i think the best telling of the rise and fall of hitler and one of the interesting things about the people that uh how should i say it um justified or maybe propped up the ideas that hitler put forward is the fact that they were extremely intelligent they were in the intellectual class they were like it was obvious that they they thought very deeply and rationally about the world so what i would like to say is one of the things that shows to me is some of the worst atrocities in the history of humanity have been committed by very intelligent people so that that means that intelligence doesn't make you a good person i wonder if um you know there's a g factor for intelligence i wonder if there's a g factor for goodness uh you know the niche uh good and evil of course that's probably harder to measure because that's such a subjective thing what it means to be good and even the idea of evil is a deeply uncomfortable thing because how do we know but it's independent whatever it is it's independent of intelligence so i i agree with you about that but let me say this i have also asserted my belief that more intelligence is better than less that doesn't mean more intelligent people are better people but all things being equal would you like to be smarter or less smart so if i had a pill i have two pills i said this one will make you smarter this one will make you dumber which one would you like are there any circumstances under which you would choose to be dumber well let me ask you this that's a very nuanced and interesting question you know there's been books written about this right um now we'll return to the hard questions the interesting questions but let me ask about human happiness this intelligence lead to happiness no so so okay so back to the pill then so why uh when would you take the pill so you said iq 80 90 100 110 you start going to the quartiles and um is it obvious isn't there uh diminishing returns and then it starts becoming negative this is an empirical question yes and so that i have advocated in many forums more research on enhancing the g factor right now there's there have been many claims about enhancing intelligence with you mentioned the n-back training it was a big deal a few years ago it doesn't work data is very clear it does not work you know or doing like memory tests like training and so on yeah yeah it makes it may give you a better memory in the short run but it doesn't impact your g factor um it was very popular a couple of decades ago that the idea that listening to mozart could make you more intelligent there was a paper published on this with somebody i knew published this paper uh intelligence researchers never believed it for a second been hundreds of studies all the meta analyses all the summaries and so on so there's nothing to it nothing to it at all but but but wouldn't it be something wouldn't it be world shaking if you could take the normal distribution of intelligence which we haven't really talked about yet but iq scores and the g factor is thought to be a normal distribution and shift it to the right so that everybody is smarter even a half a standard deviation would be world shaking because there are many social problems many many social problems that are exacerbated by people with lower ability to reason stuff out and navigate everyday life so i wonder if there's a threshold so maybe i would push back and say universal shifting of the normal distribution may not be the optimal way of shifting maybe it's better to uh whatever the asymmetric tank kind of distributions is like really pushing the lower up versus uh trying to make the uh people at the average more intelligent so you're saying that if in fact there was some way to increase g let's just call it metaphorically a pill an iq pill we should only give it to people at the lower end no it's just intuitively i i can see that life becomes easier at the lower end yes if it's increased it becomes less and less it is an empirical scientific question but it becomes less and less obvious to me that more intelligence is better at the high end it not because it would make life easier but it would make whatever problems you're working on more solvable and if you are working on artificial intelligence there's a tremendous potential to good for for that to improve society i understand so at that whatever problems you're working on yes but there's also the problem of the human condition there's love there's fear and all those beautiful things that sometimes if you're good at solving problems you're going to create more problems for yourself it's uh i'm not exactly sure so ignorance is bliss is a thing so there might be a place there might be a sweet spot of intelligence given your environment given your personality all those kinds of things and that becomes less beautifully complicated the more and more intelligent you become but that's a that's a that's a question for literature not for science perhaps imagine this imagine there was an iq pill yeah and it was developed by a private company and they are willing to sell it to you and whatever price they put on it you are willing to pay it because you would like to be smarter yes but just before they give you a pill they give you a disclaimer form to sign yes don't hold us that we you understand that this pill has no guarantee that your life is going to be better and in fact it could be worse well yes that's how lawyers work but i would love for science to answer the question to try to predict if your life is going to be better or worse when you become more uh more or less intelligent it's a it's a fascinating question about what is the sweet spot for the human condition uh some of the things we see as bugs might be actually features maybe crucial to our uh overall happiness is our limitations might lead to more happiness than less but again more intelligence is better at the lower end that's more that's as that's something that's less arguable and and and fascinating if possible to increase but you know there's virtually no research that's based on a neuroscience approach to solving that problem all the solutions that have been proposed to solve that problem or to ameliorate that problem are essentially based on the blank slate assumption that you know enriching the environment removing barriers all good things by the way i'm not against any of those things but there's no empirical evidence that they're going to improve the general reasoning ability or make people more employable have you read flowers of uh argan on yes that's to the question of intelligence and happiness there are many profound aspects of that story it was a film that was very good uh if the film was called charlie for the younger people who are listening to this uh you might be able to stream it on netflix or something but it was a story about uh a person with very low iq who underwent a surgical procedure in the brain and he slowly became a genius and the tragedy of the story is the effect was temporary it's a fascinating story really that goes in contrast to the the basic human experience that each of us individually have but it raises the question of the the full the full range of people you might be able to be uh given different levels of intelligence you've mentioned the normal distribution so let's talk about it there's a book called the bell curve written in 1994 written by psychologist richard hernstein and political scientist charles murray why was this book so controversial this is a fascinating book i know charles murray i've had many conversations with with him yeah what is the book about with the book is about the importance of intelligence in everyday life that's what the book is about it's an empirical book it has uh statistical analyses of very large databases that show that essentially iq scores or their equivalent are correlated to all kinds of social uh problems uh and social benefits and that in itself is not where the controversy about that book came the controversy was about one chapter in that book and that is a chapter about the average difference in mean scores between black americans and white americans and these are the terms that were used in the book at the time and are still used to some extent and historically or really for decades it has been observed that uh disadvantaged groups uh score on average lower than caucasians on on academic tests tests of mental ability and especially on iq tests and the difference is about a standard deviation which is about 15 points which is a substantial difference in the book hernstein and murray in this one chapter assert clearly and unambiguously that whether this average difference is due to genetics or not they are agnostic they don't know moreover they assert they don't care because you wouldn't treat anybody differently knowing that if there was a genetic component or not because that's a group average finding every individual has to be treated as an individual you can't make any assumption about what that person's intellectual ability might be from the fact of a average group difference they're very clear about this nonetheless people took away i'm going to choose my words carefully because i have a feeling that many critics didn't actually read these read the book they took away that hernstein and murray were saying that blacks are genetically inferior that was the take home message and if they weren't saying it they were implying it because they had a chapter that discussed this empirical observation of a difference and isn't this horrible and so the reaction to that book was incendiary what do we know about from that book and the research beyond uh about race differences and intelligence it's still the most incendiary topic in psychology nothing has changed that anybody who even discusses it is easily called a racist just for discussing it it's become fashionable to find racism in any discussion like this it's unfortunate the short answer to your question is there's been very little actual research on this topic since 19 since the book of since the bell curve even before this really became incendiary in 1969 with an article published by an educational psychologist named arthur jensen let's just take a minute and go back to that to see the bell curve in a little bit more historical perspective arthur jensen was a educational psychologist at uc berkeley i knew him as well and um in 1969 or 68 the harvard educational review asked him to take an uh to do a review article on the early childhood education programs that were designed to raise the iqs of minority students this was before the federally funded head start program head start had not really gotten underway at the time jensen undertook his review of what were a number of demonstration programs and these demonstration programs were for young children around kindergarten age and they were specially designed to be cognitively stimulating to provide lunches do all the the things that people thought would uh minimize this this average gap of intelligence tests there was a a strong belief among virtually all psychologists that the cause of the gap was unequal opportunity due to racism due to all you know all negative things in the society and if you could compensate for this the gap would go away so early childhood education back then was called literally compensatory education jensen looked at these programs he was an empirical guy he understood psychometrics and he wrote a it was over a hundred page article detailing these programs and the flaws in their research design some of the programs reported iq gains of on average five points but a few reported 10 20 and even 30 point gains one was called the miracle in milwaukee the that investigator went to jail ultimately for fabricating data but the point is that jensen wrote an article that said look uh the opening sentence of his article is classic the opening sentence is i may not quote it exactly right but it's we have tried compensatory education and it has failed and he showed that these games were essentially nothing you couldn't really document empirically any gains at all from these really earnest efforts to increase iq but he went a step further a fateful step further he said not only have these efforts failed but because they have had essentially no impact we have to re-examine our assumption that these differences are caused by environmental things that we can address with education we need to consider a genetic influence whether there's a genetic influence on this group difference so you said that this is one of the more controversial works i think the most infamous paper in all of psychology i would go on to say because in 1969 the genetic data was very skimpy on this question skimpy and controversial it's always been controversial but it was even skimpy and controversial it's kind of a long story that i go into a little bit in more detail in the book neuroscience of intelligence but to say he was vilified is an understatement i mean he couldn't talk it at the american psychological association without bomb threats clearing the the lecture hall campus security watched him all the time they opened his mail he had to retreat to a different address this was one of the earliest kinds this is before the internet and and kind of internet social media mobs but it was that intense and i have written that overnight after the publication of this article all intelligence research became radioactive nobody wanted to talk about it uh and then it it it didn't it nobody was doing more research and then the bell curve came along and the johnson controversy was dying down i have stories that jensen told me about his interaction with the nixon white house on this issue i mean it was this was like a really big deal it was some unbelievable stories but you know he told me this so i kind of believe these stories nonetheless 25 years later 25 years later all the silence basically saying you know this uh nobody wants to do this kind of research there's so much pressure so much attack against this kind of research and here's uh sort of a bold stupid crazy people that decide to dive right back in and i wonder how much discussion that was do we include this chapter or not murray has said they discussed it and they felt they should include it and they were very careful in the way they they wrote it which did them no good yeah so as a matter of fact when the bell curve came out it was so controversial i got a call from a television show called nightline it was with a broadcaster called ted koppel who had this evening show i think was on late at night talked about news it was a straight up news thing yeah and producer called and asked if i would be on it to talk about the uh the bell curve and i said you know it it she asked me what i thought about the bell curve as a book i said look it's a very good book it talks about the role of intelligence in society and she said no no what do you think about the chapter on race that's what we want you to talk about i remember this conversation i said well she said what would you say if you were on tv and i said well what i would say is that it's not at all clear if there's any genetic component to intelligence um any differences but if there were a strong genetic component that would be a good thing and you know complete silence on the other end of the phone yeah and she said well what do you mean and i said well if it's the more genetic any difference is the more it's biological and if it's biological we can figure out how to fix it i see that's interesting she said would you say that on television yes i said no and so that was the end of that so that's for more like uh biology is um within the reach of science and the environment is a public policy social and all those kinds of things it's it from your perspective whichever one you think is more amenable to solutions in the in the short term is the one that excites you but um you're saying that it's good uh the truth of genetic differences no matter what the between groups is is a painful harmful potentially potentially dangerous thing so let me ask you to this question whether there's bell curve or any research on race differences can that be used to increase the amount of racism in the world can that be used to increase the amount of hate in the world do you think about this kind of stuff i've thought about this a lot not as a scientist but as a person and my sense is there is such enormous reservoirs of hate and racism that have nothing to do with scientific knowledge of the data that speak against that that no i don't i don't want to give racist groups of veto power over what scientists study if you think that the differences and by the way virtually no one disagrees that there are differences in scores it's all about what causes them and how to fix it so if you think this is a cultural problem then you must ask the problem what do you want do you want to change anything about the culture or are you okay with the culture because you don't feel it's appropriate to change a person's culture so are you okay with that and the fact that that may lead to disadvantages in in school achievement it's a question are if you think it's environmental what are the environmental parameters that can be fixed i'll tell you one lead in you know led from gasoline in the atmosphere lead in paint lead in in water that's an environmental toxin that society has the means to eliminate and they should yeah just to sort of trying to find some insight and conclusion to this very difficult topic uh is there been research on environment versus genetics nature versus nurture on this question of race differences there is not no one wants to do this research it's first of all it's hard research to do second of all it's it's a minefield no one wants to spend their career on it tenured people don't want to do it let alone students the way i talk about it i well before i tell you the way i talk about i want to say one more thing about jensen he was once asked by a journalist straight out are you a racist his answer was very interesting his answer was i've thought about that a lot and i've concluded it doesn't matter this now i i know what he meant by this the guts to say that wow he was a very unusual person i think he had a touch of asperger's syndrome to tell you the truth because i i saw him in many circumstances he would be cancelled on twitter immediately with that sentence yeah but what he what he meant was he had a hypothesis yeah and with respect to group differences he called it the default hypothesis he said whatever factors affect individual intelligence are likely the same factors that affect group differences it was the default but it was a hypothesis it should be tested and if it turned out empirical test didn't support the hypothesis he was happy to move on to something else he was absolutely committed to that scientific ideal that that it's an empirical question we should look at it and let's see what happens the scientific method cannot be racist from his perspective it doesn't matter what the scientists if they if they follow the scientific method it doesn't matter what they believe and if they are biased and they consciously or unconsciously bias the data other people will come along to replicate it they will fail and the process over time will work so let me push back on this idea because psychology to me is full of gray areas and what i've observed about psychology even replication crisis aside is that something about the media something about journalism something about the the virality of ideas in the public sphere they misinterpret they take up things from studies willfully or from ignorance misinterpret findings and tell narratives around that i personally believe for me i'm not saying that broadly about science but for me it's my responsibility to anticipate the ways in which findings will be misinterpreted so i've had i thought about this a lot because i publish papers on uh semi-autonomous vehicles and those you know cars people dying cars there's people that have written me a letter saying emails nobody writes letters i wish they did uh that i have blood in my hands because of things that i would say positive or negative there's consequences in the same way when you're a researcher for intelligence i'm sure you might get emails or at least people might believe that finding your study is going to be used by a large number of people to increase the amount of hate in the world i think there's some responsibility on scientists but for me i think there's a great responsibility to anticipate the ways things will be misinterpreted and there you have to first of all decide whether you want to say a thing at all or do the study at all publish the study at all and to the words with which you explain it it's uh i find this on twitter a lot actually which is when i when i write a tweet i'm usually just doing so innocently i i'll i'll i'll write it you know it takes me like five seconds to write it or whatever 30 seconds to write it and then i'll think all right i like close my eyes open and try to see how will the world interpret this like what are the ways in which this will be misinterpreted and i'll sometimes adjust that tweet to see like yeah so in my mind it's clear but that's because it's my mind from which this tweet came but you have to think in a fresh mind that sees this uh and it's spread across a large number of other minds how will the interpretation morph i mean for a tweet it's a silly thing it doesn't matter but for a scientific paper and study and finding i think it matters so i don't know i don't know what your thoughts about that because maybe for jensen uh the data is there what do you want me to do this is a scientific process has been carried out if you think the data was polluted by bias do other studies that reveal the bias uh but the data is there and we like i have would i'm not a poet i'm not a uh literary right like what do you want me to do i'm just presenting you the data what do you think on that spectrum what's the role of a scientist the reason i do podcasts yeah the reason i write books for the public is to explain what i think the data mean and what i think the data don't mean i don't do very much on twitter other than to retweet uh references to papers yes i don't think it's my role to explain these because they're complicated they're nuanced but when you decide not to do a scientific study because you're or not to publish a result because you're afraid the result could be could be harmful or insensitive that's not an unreasonable thought and people will make different conclusions and decisions about that i wrote about this i wrote i i'm the editor of a journal called intelligence which published which publishes scientific papers sometimes we publish papers on group differences those papers sometimes are controversial these papers are written for a scientific audience they're not written for the twitter audience so i don't promote them very much on on twitter but in a scientific paper you have to now choose your words carefully also because those papers are picked up uh by non-scientists by writers of various kinds and you have to be available to discuss what you're saying and what you're not saying sometimes you are successful at having a good conversation like we are today that's that doesn't start out pejorative other times i've been asked to participate in debates where my role would be to justify race science well you can see just start out you know and that was a bbc request that i had that i received i have so much it's a love-hate relationship mostly hate with these shallow journal uh journalism organizations so they would want to use you as a kind of in a debate setting to communicate as to like there is raise differences between groups and make that into debate yes and put you in a role of um justifying racism you justify that's what they're asking me to do courses like educating about this this field of the science of intelligence yeah i i want to say one more thing before we get off the the normal distribution you also asked me what is the science after the bell curve and the short answer is there's not much new work but whatever work there is supports the idea that there still are group differences it's arguable whether those differences have diminished at all or not and there is still a major problem in underperformance in for school achievement for many uh mis disadvantaged and minority students and there's so far is no way to fix it uh what do we do with this information what uh is this is this now a task now we'll talk about the future uh on the neuroscience and the biology side but in terms of this information as a society in the public policy in the political space in the social space what do we do with this information i've thought a lot about this the first step is to have people interested in policy understand what the data actually show to pay attention to intelligence data you can read policy papers about education and using your word processor you can search for the word intelligence you can search a twenty thousand word document in a second and find out the word intelligence does not appear anywhere in most discussions about what to do about achievement gaps i'm not talking about test gaps i'm talking about actual achievement gaps in schools which everyone agrees is a problem the word intelligence doesn't appear among educators that's fascinating as a matter of fact in california there has been tremendous controversy about recent attempts to revise the curriculum for math in high schools and we had a stanford professor of education who was running this review assert there's no such thing as talent of mathematical talent and she wanted to get rid of the advanced classes in math because you know not everyone could do that now of course this has been very controversial they've retreated somewhat but the idea that a university professor was in charge of this who believes not that there's no talent that doesn't exist this is rather shocking let alone the complete absence of intelligence data by the way let me tell you something about what the intelligence data show let's take race out of it uh even though the origins of these studies uh were a long time ago um i'm blocking on the name of the report the coleman report was a famous report about education and they measured all kinds of variables about schools about teachers and they looked at academic achievement as an outcome and they found the most predictive variables of education outcome were the variables the student brought with him or her into the school essentially their ability and that when you combine the school and the teacher variables together the quality of the school the funding of the school the quality of the teachers their education you put all the teacher and school variables together it barely accounted for 10 of the variants and this has been replicated now you know so the best research we have shows that school variables and teacher variables together account for about 10 of student academic achievement now you want to have some policy on improving academic achievement how much money do you want to put into teacher education how much money you want to put into the quality of of of the school administration you know who you can ask you can ask the gates foundation because they spent a tremendous amount of money doing that and they at the end of it because they're measurement people they want to you know they want to know the data they found it had no impact at all and they've kind of pulled out of of that kind of program so oh boy let me ask let me ask you this is me talking but there's just the two of us well just the two of us but i'm gonna say uh some funny and ridiculous things so it's you're surely you're not approving of it uh but there's a movie called clerks you probably i've seen it i've seen it yeah there's a funny scene in there where a lovely couple are talking about the number of previous sexual partners they had and uh uh the woman says that i believe she just had a handful like two or three or something like that sexual partners but then she also mentioned um that she um what's that called fellatio what's the scientific but she went you know gave a to uh 37 guys i believe it is and so that has to do with the truth so sometimes knowing the truth can get in the way of a successful relationship of love of some of the human flourishing and that's seems to me that's at the core here that facing some kind of truth that's not able to be changed it makes it difficult to sort of it's limiting as opposed to empowering that's the concern if you sort of test for intelligence and lay the data out it feels like you will give up on certain people you will you'll sort of start bidding people it's like well this is this person is like let's focus on the average people or let's focus on the very intelligent people that's the concern and and there's a kind of intuition that if we just don't measure and we don't use that data then we would treat everybody equal and give everybody equal opportunity if we have the data in front of us we're likely to misdistribute the amount of sort of attention we allocate resources we allocate uh allocate to people that's that's probably the concern it's a realistic concern and but i think it's a misplaced concern if you want to fix the problem if you want to fix the problem you have to know what the problem is now let me let me tell you this let's go back to the bell curve for not the bell curve but the normal distribution yes 16 of the population on average has an iq under 85 which means they're very hard if you have an iq under 85 it's very hard to find gainful employment at a salary sustains you at least minimally in modern life okay not impossible but it's very difficult 16 of the population of the united states is about 51 or 52 million people with iqs under 85. this is not a small issue 14 million children have iqs under 85. is this something we want to ignore does this have any what is the venn diagram between you know when you have people with iqs under 85 and you have achievement in school or achievement in life there's a lot of overlap there this is why to go back to the iq pill if there were a way to shift that curve toward the higher end that would have a big impact if i could maybe before we talk about the impact on life and so on um some of the criticisms of the bell curve so stephen j good wrote that the bell curve rests on four incorrect assumptions it would be just interesting to get your thoughts on the four assumptions which are intelligence must be reducible to a single number intelligence must be capable of rank ordering people in a linear order intelligence must be primarily genetically based and intelligence must be essentially immutable um maybe not as criticisms but as thoughts about intelligence yeah that we could we could spend a lot of time on him yeah he wrote that in what about 1985 1984. he his views were overtly political not scientific he was a scientist but his views on this were overtly political and i would encourage people listening to this if they really want to understand his criticisms they should just google what he had to say and google the scientific reviews of his book the mismeasure of man and they will take these statements apart they were wrong not only were they wrong but when he asserted in his first book that you know that there was no biological basis essentially to iq by the time the second edition came around there were studies of mri mris of showing that brain size brain volume were correlated to iq scores which he declined to put in his book so i'm learning a lot today i didn't know i didn't know the actually the extent of his work i was just using a few little snippets of criticism that's interesting so there's a battle here he wrote a book miss measure of man that's not that's missing a lot of these scientific uh his grounding book is highly popular in colleges today you can find it in any college bookstore under a signed reading it's highly popular in this measure of men yes highly influential can you speak to the miss measurements i'm i'm undereducated about this so what is this the book basically criticizing yeah the ideas in the bulk yeah yeah where those four things came from and it is really um a book that was uh really taken apart point by point by a number of people who actually understood the data and he didn't care yeah he didn't care he didn't it's a politically listen uh because this is such a sensitive topic like i said i believe uh the the impact of the work as it is misinterpreted has to be considered because it's not just going to be scientific discourse it's going to be political discourse there's going to be debates there's going to be politically motivated people that will use messages in each direction make it the make something like the bell curve the enemy or the support for your uh for for one's racist beliefs and so uh i think you have to consider that but it's difficult because you know nietzsche was used by hitler to justify a lot of his beliefs and it's not in it's not exactly unneeded to to anticipate hitler so uh or how his ideas will be misinterpreted and used for evil but there is a balance there so i understand this is really interesting i didn't i didn't know is there any criticism of the book you find compelling or interesting or challenging to you from a scientific perspective there were factual criticisms about the nature of the statistics that were used the statistical analyses these were more technical criticisms and they were addressed by murray in a couple of articles where he took all the criticisms and and spoke to them and people listening to this podcast uh can certainly find all those online uh it's very interesting but murray went on to write some additional books two in the last couple of years uh one about human diversity where he goes through the data refuting the idea that race is only a social construct with no biological meaning he he discusses the data it's a very good discussion you don't have to agree with it but he presents data in a cogent way and he talks about the critics of that and he talks about their data in a cogent non-personal way it's it's a it's a very informative discussion a book is called human diversity he talks about race and he talks about gender same thing about sex differences and more recently he's written what might be his final say on this a book called facing reality where he talks about this again uh so you know he he can certainly defend himself he doesn't need me to to do that but i would urge people who have heard about him and the bell curve and who think they know what's in it you are likely incorrect and you need to read it for yourself but it is uh so scientifically it's a it's a serious subject it's a difficult subject ethically it's a difficult subject everything you said here calmly and thoughtfully is difficult this is difficult for me to even consider that g factor exists um i don't mean from like that somehow g factors inherently racist or sexist or whatever it's just it's it's difficult in the way that concerning the fact that we die one day is difficult that we are limited by our biology it's difficult and it's um at least from an american perspective you like to believe that everything is possible in this world well that leads us to what i think we should do with this information [Laughter] and what i think we should do with this information is unusual uh oh because i think what we need to do is fund more neuroscience research on the molecular biology of learning and memory because one definition of intelligence is based on how much you can learn and how much you can remember yes and if you accept that definition of intelligence then there are molecular studies going on now and nobel prize is being won on molecular biology or molecular neurobiology of learning and memory now the step those researchers those scientists need to take when it comes to intelligence is to focus on the concept of individual differences intelligence research has individual differences as its heart because it it is it assumes that people differ on this variable and those differences are meaningful and need understanding cognitive psychologists who have morphed into molecular biologists studying learning and memory hate the concept of individual differences historically some now are coming around to it i once sat next to a nobel prize winner for his work on uh on on memory and i asked him about uh individual differences and he said don't go there it'll set us back 50 years but i said i said don't you think they're the key though to understand why can some people remember more than others he said you you don't want to go there i think the 21st century will be remembered by the technology and the science that goes to individual differences because we haven't we have now data we have now the tools that much much better to start to measure stuff to estimate uh not just on the sort of through tests and like iq test type of things sort of uh outside the body kind of things but measuring all kinds of stuff about the body so yeah truly going to the molecular biology to the neurobiology to the neuroscience let me ask you about in the life does intelligence correlate uh with or lead to or has anything to do with career success you've mentioned these kinds of things and um is there any data you've had an excellent conversation with jordan peterson for example is there any data on what intelligent means for success in life success in life there is a tremendous amount of validity data that looked at intelligence test scores and various measures of life success now of course life success is a pretty broad topic and not everybody agrees on you know what success means but there's general agreement on certain aspects of success that can be measured uh and uh including life expectancy like you said life expectancy now there's life success uh you know uh life expectancy uh i mean though that is such an interesting finding but it you know iq scores are also correlated to things like income now okay so who thinks income means you're successful that's not the point the point is that income is one empirical measure in this culture that says something about your level of success now you can define success in ways that have nothing to do with income you can define success based on your evolutionary natural selection success you know you but for variables uh yeah and even that by the way is correlated to iq in in in some uh studies so however you want to define success iq is important it's not the only determinant people get hung up on well what about personality what about so-called emotional intelligence yes all those things matter the thing that matters empirically the single thing that matters the most is your general uh ability your general mental intellectual ability your reasoning ability and the more complex your vocation the more complex your job the more g matters g doesn't matter in a lot of occupations don't require complex thinking and there are occupations like that and g doesn't matter within an occupation the g might not matter so much so that if you look at all the professors at mit and had a way to rank order them on you know there's a ceiling effect is what i'm saying that you know also when you get past a certain threshold then there's impact on wealth for example or career success uh however that's defined in each individual discipline but after a certain point it doesn't matter actually it does matter in certain things so for example there is a very classic study uh that was started at johns hopkins when i was a graduate student there i actually worked on this study at the very beginning the study of mathematically and scientifically precocious youth and they gave junior high school students age 11 and 12 the standard s.a.t math exam and they found a very large number of students scored very high on this exam not a large number i mean they they found many students when they cast the net to all of baltimore they found a number of students who scored as high on the s.a.t math when they were 12 years old as incoming hopkins freshmen and they said gee now this is interesting what shall we do now and on a case-by-case basis they got some of those kids into their local community college math programs many of those kids went on to be very successful and now there's a 50-year follow-up of those kids and it turns out if these kids were in the top one percent okay so everybody in this study is in the top one percent if you take that group that rarefied group and divide them into quartiles so that you have the top 25 percent of the top one percent and the bottom 25 percent of the top one percent you can find on measurable variables of success the top quartile does better than the bottom quartile in the top one percent they have more patents they have more publications they have more tenure at universities and this is based on their you're dividing them based on their score at age 12. i wonder how much interesting data is in the variability in the differences so but that that's really that that's oh boy that's very interesting but it's also i don't know somehow painful i don't know why it's so painful that that's so that g factor so determinant of even at in the nuanced topic it's interesting that you find that painful do you find it painful that people with charisma are very successful can be very successful in life even though having no other attributes other than they're they're famous and people like them do you feel that painful yes if that charisma is untrainable so one of the things again this is like i learned psychology from the johnny depp trial but one of the things the psychologist the personality psychologist he could maybe speak to this because he had interest in this for time is uh she was saying that personality technically speaking is the thing that doesn't change over a lifetime it's the it's the thing you're i don't know if she was actually implying that you're born with it well it's a trait it's a trait that's right that's relatively stable over time that i think that's generally correct so to the degree your personality is stable over time yes that too is painful because what's not painful is the thing you know if i'm fat and out of shape i can exercise and you know uh become healthier in that way if my diet is a giant mess and that's resulting in some kind of uh conditions that my body is experiencing i can fix that by having a better diet that sort of my actions my willed actions can make a change if charisma is part of the personality that's the part of the charisma that is part of the personality that is stable yeah yeah that's painful too because it's like oh i'm stuck with this i'm stuck with this well i mean and this pretty much generalizes to every aspect of your being this is who you are you've got to deal with it and what it undermines of course is a realistic appreciation for this undermines the fairly recent idea prevalent in this country that if you work hard you can be anything you want to be which has morphed from the original idea that if you work hard you can be successful those are two different things yeah and now we have if you work hard you can be anything you want to be this is completely unrealistic i'm sorry it just is now you can work hard and be successful there's no question but you know what the heart i could work very hard and i am not going to be a successful uh theoretical physicist i'm just not that said i mean we should because we had this conversation already but it's good to repeat the fact that you're not going to be a theoretical physicist is not judgment on your basic humanity returning again to the all men which means men and women are created equal so again some of the differences we're talking about in quote-unquote success wealth uh number of uh whether you win a nobel prize or not that doesn't um put a measure on your basic humanity and the basic value and even goodness of you as a human being because that your basic role and value in society is largely within your control uh it's it's some of these measures that we're talking about uh it's good it's good to remember this um one question about the flynn effect what is it are humans getting smarter over the years over the decades over the centuries the flint effect is james flynn who passed away about a year ago published a a set of analyses going back a couple of decades when he first noticed this that iq scores when you looked uh over the years seemed to be drifting up now this was not unknown to the people who make the test because they renormed the test periodically and they have to renorm the test periodically because what 10 items correct meant relative to other people 50 years ago is not the same as what 10 items mean relative today people are getting more things correct now the scores have been drifting up about three points iq scores have been drifting up about three points per decade this is not a personal effect this is a cohort effect well it's not for an individual but the world what how do you explain so what's that and this has presented intelligence researchers with a great mystery two questions first is it effect on the fifty percent of the variance that's the g factor or on the other fifty percent and there's evidence that it is a g factor effect and second what on earth causes this and doesn't this mean intelligence and g factor cannot be genetic because the scale of natural selection is much much longer than a couple of decades ago and so it's been used to try to undermine the idea that there can be a genetic influence on intelligence but certainly it can be the flint effect can affect the non-genetic aspects of intelligence because genes account for maybe 50 of the variance may be higher it could be as high as 80 percent for adults but let's just say 50 percent for discussion um so the the flint effect is it's still a mystery it's still in this shape it's still a mystery although the evidence is coming out i told you before i edit a journal on intelligence and we're doing a special issue in honor of james flynn so i'm starting to see papers now on the really the latest research on this um i think most people who specialize in this area of trying to understand the flint effect uh are coming to the view based on data that it has to do with advances in nutrition and health care and there's also evidence that the effect is slowing down and possibly reversing oh boy so how would nutrition so nutrition would still be connected to the g factor so nutrition as it relates to the g factor so the biology that leads to the intelligence yes that would be the claim like uh the the the hypothesis being tested by the research yes and there's some evidence from from infants um that nutrition has has made a difference and so it's not an unreasonable connection but does it negate the idea that there's a genetic influence not logically at all so but it is very interesting so that if you take an iq test today but you normal but you take the score and use the tables that were available in 1940 you're going to wind up with a much higher iq number so are we really smarter than a couple of generations ago no but we might be able to solve problems a little better and make use of our rg because of things like sesame street and other curricula in school more people are going to to to to school uh so there are a lot of factors here to disentangle it it's fascinating though it's fascinating that there's not clear answers yet that as a population we're getting smarter we just zoom out that's what it looks like as a population getting smarter it's interesting to see what the effects of that are i mean this raises the question we've mentioned it many times but haven't clearly addressed it which is nature versus nurture questions so how much of intelligence is nature how much of it is nurture how much of it is determined by genetics versus environment all of it all of it is genetics no all of it is nature and nurture yeah so yes yes okay uh how much of the variance can you apportion to either yeah most of the people who work in this field say that that is a the framing of that if if the question is framed that way it can't can't be answered because nature and nurture are not two independent influences they interact with each other and understanding those interactions is so complex that many behavioral geneticists say it it is today impossible and always will be impossible to disentangle that no matter what kind of advances there are in dna technology and genomic informatic informatics but they're still to push back on that that same intuition from behavioral geneticists would lead me to believe that there cannot possibly be a stable g factor because it's super complex many of them would assert that as a logical outcome [Music] but because i believe there is a stable g vector from lots of sources of data not just one study but lots of sources of data over decades i am more amenable to the idea that whatever interactions between genes and environment exist they can be explicated they can be studied and they that information can be used as a basis for molecular biology of intelligence yes so and we'll do this exact question because is it doesn't the stability of the g factor give you at least a hint that there is a biological basis for intelligence yes i i think it's clear that the fact that an iq score is correlated to things like thickness of your cortex that is correlated to glucose metabolic rate in in your brain that that identical twins reared apart are highly similar in their iq scores these are all important observations that certainly more than that indicate not just suggest but indicate that there's a biological basis and does anyone believe intelligence has nothing to do with the brain i mean it's so obvious well indirectly definitely has to do with it but the question is environment interacting with the brain or is it the actual raw hardware of the brain well some would say that the raw hardware of the brain as it develops from conception through adulthood or at least through the childhood that that that so-called hardware that you are assuming is mostly genetic in fact is not as deterministic as you might think that it is probabilistic and what affects the probabilities are things like in uterine environment and other factors like that including chance that chance affects the way the neurons are connecting during gestation it's not hey it's pre-programmed so there's there is pushback on the concept that genes provide a blueprint that is a lot more fluid well but also yeah so there's a lot a lot a lot happens in the first few months of development uh so for in in nine months in inside the mother's body and in the uh in and you know the the months the few months afterwards there's a lot of fascinating stuff like including chance and luck like you said how things connect up man the question is afterwards the neuroplasticity of the brain how much adjustment there is relative to the environment how much that affects the g factor but that's where the the whole conclusions of the studies that we've been talking about is that seems to have less and less and less of an effect as uh pretty quickly as yes and i do think there is more of a genetic by my view and i'm not an expert on this i mean genetics is a highly technical and complex subject i am not a geneticist not a behavioral geneticist but but my reading of this my interpretation of this is that there is a genetic blueprint more or less and that has a profound influence on your subsequent intellectual development including the g factor and that's not to say things can't happen to i mean if you think of that genes provide a potential fine and that various variables impact that potential and every parent of a newborn implicitly or explicitly wants to maximize that potential this is why you buy educational toys this is why you pay attention to organic baby food this is why you do all these things because you want your baby to be as healthy and as smart as possible and every parent will say that is there a case to be made can you steel man the case that genetics has is a very tiny component of all this and the environment is essential i don't think the data supports that genetics is a tiny component i think the data support the idea that the genetics is a very important and i don't say component i say influence very important influence and the environment is a lot less than people believe most people believe environment plays a big role i'm not so sure guess what i'm asking you is can you see where what you just said it might be wrong can you can you imagine a world and what kind of evidence would you need to see to say you know what the intuition the studies so far like reversing the directions so one of the cool things we have now more and more is we're getting more and more data and the the rate of the data is is is escalating because of the digital world so when you start to look at a very large scale of data both on the biology side and the social side we might be discovering some very counterintuitive things about society we might see the edge cases that reveal that if we actually scale those edge cases and they become like the norm that will have a complete shift in our like you'll see g factor be able to be modified throughout life in the teens and in the in in later life so a is in any case you can make or for well your current intuitions are wrong yes and it's a good question because i think everyone should always be asked what evidence would change your mind yeah uh it's certainly not only a fair question it is really the key question for anybody working on any aspect of science i think that if environment was very important we would have seen it clearly by now it would have been obvious that school interventions compensatory education early childhood education all these things that have been earnestly tried in well-funded well-designed studies which show some effect and they don't they don't what what if the school the way we've tried school compensatory school sucks and when you what everybody said at the beginning that's what everybody said to jensen he said well maybe these maybe we need to start earlier maybe we need not do uh pre-kindergarten but pre-pre-kindergarten yeah it's always an infinite well maybe we didn't get it right but after decades of trying 50 years 50 or 60 years of trying surely something would have worked to the point where you could actually see a result and not need a a probability level at .05 on some means so that's why i that's the kind of evidence that would change my mind population level interventions like schooling that you would you would see um like this actually has an effect yes and when you take adopted kids and they grow up in a another family and you find out when those adopted kids are adults their iq scores don't correlate with the iq scores of their adoptive parents but they do correlate with their iq scores of their biological parents who whom they've never met i mean these are important these are powerful observations and it would be convincing to you if the reverse was true yes that would be more now and there is some data on adoption that indicates that the adopted children are moving a little bit more toward their their adoptive parents but it's you know it it's to me the overwhelming the way i have this concept called the weight of evidence where i don't interpret any one study too much the weight of evidence tells me genes are important but what does that mean what does it mean that genes are important knowing that gene expression genes don't express themselves in a vacuum they express themselves in an environment so the environment has to have something to do with it especially if the best genetic estimates of the amount of variants that are around 50 or even eight even if it's as high as 80 percent it still leaves 20 percent of non-genetic now maybe that is all uh luck maybe that's all chance i could believe that i could easily believe that so um but i i do think after 50 years of trying various interventions and nothing works including memory training including listening to mozart including playing computer games none of that has shown any impact on intelligence test scores is there data on the intelligence the iq of parents as it relates to the children yes and there is some evident genetic evidence of kind of of of an interaction between the parents iq and the environment that high iq parents provide an enriched environment which then can impact the child in addition to the genes it's that environment so there are all these interactions that you know um but it's not you know think about the number of books in a household this was a variable that's correlated with iq and and uh it is yeah well well why especially if the kid never reads any of the books it's because more intelligent people have more books in their house and if you're more intelligent and there's a genetic component to that the child will get those genes or some of those genes as well as as the environment but it's not the number of books in the house that actually directly impacts the child so the two scenarios on this are you find that and this was used to get rid of the s.a.t test oh the sat scores highly correlated with the social economic status of the parents so all you're really measuring is how rich the parents are okay well why are the parents rich yes and so you could the opposite kind of uh syllogism is that people who are very bright make more money they can afford homes in in better neighborhoods so their kids get better schools now the kids grow up bright where in that chain of events does that come from well unless you have a genetically informative research design where you look at siblings that have the same biological parents and and so on you can't really disentangle all that most studies of social economic status and intelligence do not have a genetically informed design so any conclusions they make about the causality of the social economic status being the cause of the iq is is a stretch and where you do find genetically informative designs you find most of the variants in your outcome measures are due to the genetic component and sometimes the ses adds a little but uh the weight of evidence is it doesn't add very much variance to predict what's going on beyond the genetic variance so when you actually look at it in in in some and there aren't that many studies that have genetically informed designs uh but when you you do see those the genes seem to have an advantage sorry for the strange questions but there's is there a connection [Music] um fertility or the number of kids that you have and g factor so you know the kind of conventional wisdom is people of maybe is it higher economic status or something like that or having fewer children i just loosely hear these kinds of things is there is there data are that you're aware of in one direction or another on this well strange questions always get strange answers yes right uh yeah do you have a strange answer for that stranger the answer is there used to there were some studies that indicated the more children in a family the the firstborn children would be more intelligent than the fourth or fifth or sixth it's not clear that those studies hold up over time and of course what you see also is that families where there are multiple children four five six seven you know really big families uh the social economic status of those families usually in the modern age is not that high uh it maybe it used to be the aristocracy used to have a lot of kids i'm not sure exactly but there there there have been reports uh of uh correlations between iq and fertility um but i'm not sure that the data are very strong that the firstborn child is always the smartest it seems like there's some data to that but i'm not current on that how would that be explained that would be an uh a nurture well it could be nurture it could be in uterine environment i mean boy the biology is complicated and this is why this you know like many areas of science you you said earlier that there are a lot of gray areas and no definitive answers this is not uncommon in science that the closer you look at a problem the more questions you get not the fewer questions because the universe is complicated and the idea that we have people on this planet who can study the first nanoseconds of the big bang that's pretty amazing and i've always said that if they can study the first nanoseconds of the big bang we can certainly figure out something about intelligence that allows that i'm not sure what's more complicated the human mind or the physics of the universe uh it's unclear to me i think we over a very humbling statement maybe it's very human-centric egotistical statement that our mind is somehow super complicated but biology is a tricky one to unravel consciousness what is that well i i've always believed that consciousness and intelligence are the two real fundamental problems of the human brain and i and i and therefore i think they must be related uh yeah and heart problems like uh walk together holding hands kind of kind of kind of idea you may not know this but i i did some of the early research on anesthetic drugs with brain imaging trying to answer the question what part of the brain is the last to turn off when someone loses consciousness and is that the first part of the brain to turn on when consciousness is regained and i was working with an anesthesiologist named mike alkire who was really brilliant at this these were really the first studies of brain imaging uh using positron emission tomography long before uh fmri and you would inject a radioactive sugar that labeled the brain and the harder the brain was working the more sugar it would take up and then you could make a picture of glucose use in the brain and we he he was amazing he managed to do this in normal volunteers he brought in and anesthetized as if they were going into surgery and he managed all the human subjects requirements on this research and uh it was he was brilliant at this and and what we did is we had these normal volunteers come in on three occasions on one occasion he gave them enough anesthetic drug so they were a little drowsy and on another occasion they came in and he fully anesthetized them and you know he would say you know mike can you can you hear me and the person would say uh yeah you know that's him and then that we would scan people under the and under uh no anesthetic condition so same person and um we were looking to see if we could see the part of the brain turn off you subsequently tried to do this with fmri which has a faster time resolution and you could do it in real time as the person went under and then regained consciousness where you couldn't do that with pet you had to have three test and the results were absolutely fascinating we did this with different anesthetic drugs and different drugs impacted different parts of the brain so we were naturally looking for the common and it seemed to have something to do with the thalamus and consciousness this was actual data unconsciousness real con actual consciousness what part of the brain turns on uh what part of the brain turns off it's not so clear but maybe has something to do with the thelma the the the sequence of events seem to have the thalamus in it boy um now here's the question are some people more conscious than others are there individual differences in consciousness and i don't mean it in the um psychedelic sense i don't mean it in the political consciousness sense i just mean it in everyday life to some people go through everyday life more conscious than others and are those the people we might actually label more intelligent so now the other thing i was looking for is whether the parts of the brain we were seeing in the anesthesia studies were the same parts of the brain we were seeing in the intelligence studies now this is you know this was very complicated expensive research we didn't really have funding to do this we were trying to do it on the fly i'm not sure anybody has pursued this you know i i'm retired now uh he's gone on to other things but it's i think it's an area of research that that would be fascinating to see the parts and there are a lot more imaging studies now of consciousness i'm just not up on them so but basically the question is which imaging so newer imaging studies to see in high resolution spatial and temporal way which part of the brain lights up uh when you're doing intelligence tasks and which parts of the brain lights up when you're doing consciousness tasks and see the interplay between them you try to infer that's the challenge of neuroscience without understanding deeply looking from the outside try to infer something about uh how the whole thing works well imagine this here's a simple question does it take more anesthetic drug to put to to have a person lose consciousness consciousness if their iq is 140 then a person with an iq of 70. that's an interesting way to study it yeah i mean if there is if there is a yeah if the answer to that this is a stable yes that's very interesting so i tried to find out and i went to some anesthesiology textbooks about how you you dose and they dose by weight and what i also learned this is a little bit off subject anesthesiologists are never sure if you how deep you are yeah and they usually tell by poking you with a needle and if you don't jump they tell the surgeon to go ahead i'm not sure that's literally true but it's well it might be very difficult to know precisely how deep you are it has to do with the same kind of measurements that you're doing with the consciousness with the it's it's it's difficult it's difficult to know so i don't lose my train of thought i couldn't find in the textbooks anything about dosing by intelligence i asked my friend the anesthesiologist he said no he doesn't know i said can we do a chart review and look at people using their years of education as a proxy for iq because if someone's gone to graduate school that tells you something you can make some inference as opposed to someone who didn't graduate high school you know can we do a chart review and he says no they they never really put down the the exact dose and no he said no so to this day that the the the the simple question does it take more anesthetic drug to put someone under if they have a high iq or less or less it could go either way because by the way our early pet scan studies of intelligence found the unexpected result of an inverse correlation between glucose metabolic rate and intelligence it wasn't how much a brain area lit up how much it lit up was negatively correlated to how well they did on the test which led to the brain efficiency hypothesis which is still being studied today and there's more and more evidence that the efficiency of brain information processing is more related to intelligence than than than just more activity yeah and it'll be interesting again that's the total hypothesis how much in the relationship between intelligence and consciousness it's not obvious that those two if there's correlation that would be uh they could be inversely correlated wouldn't that be funny if you uh the the consciousness factor the c factor plus the g factor equals one it's a nice trade-off you get you get you get a trade-off how deeply you experience the world versus how deeply you're able to reason through the world what a great hypothesis certainly somebody listening to this can do this study even if it's the aliens analyzing humans uh a few centuries from now let me ask you from an ai perspective um i don't know how much you've thought about machines but and you know there's the famous touring test test of intelligence for machines um which is a beautiful almost like uh cute formulation of intelligence that alan turing proposed basically conversation being if you can fool a human to think that a machine is is a human that passes the test i suppose you could do a similar thing um for humans if i can fool you that i'm intelligent then that's a good test of intelligence right like uh you're you're talking to two people and my your your your the test is saying who has a higher iq and uh it's an interesting test because yeah maybe charisma can be very useful there uh and you're only allowed to use conversation which is the formulation of the turing test anyway all that to say is what are good tests of intelligence for machines you know we uh what do you think it takes to achieve human level intelligence for machines well i have thought a little bit about this but you know i every time i i think about these things i rapidly reach the limits of my knowledge and and imagination so when um alexa first came out and i i think um there was a a competing one well there was siri with apple and google had alexa no no uh amazon had alexa yeah amazon had a lot of google assistant something so i i proposed to one of my colleagues that he buy one of these each you know one of each and then ask it questions from the iq test yes but it became apparent that they all searched the internet so they all can find answers to questions like how far is it between washington and miami and repeat after me now i don't know if you said to uh alexa i'm going to uh re repeat these numbers backwards to me i don't know what would happen i've never done it but the the so so one answer to your question is try you're going to try it right now let's try it let's try it no yes sir so i i it would actually probably go to google search and it will be all confusing kind of stuff it would uh it would fail well then i guess that there's a test that that it would fail well but that's not that has to do more with the you know uh the language of communication versus the content so if you did an iq test to a person who doesn't speak english and the test was administered in english that's not really the test of well let's think about the computers that beat the jeopardy champions yeah so that so that because i happen to know how those are programs are very hard-coded and there's definitely a lack of intelligence there there's uh something like iq tests uh there's a there's a guy uh artificial intelligence researcher uh francois chole he's he's a google he's one of the seminal people in machine learning he also as a fun aside thing uh develop an iq test for machines oh i'll actually email you this because it would be very interesting for you it doesn't get much attention because people don't know what to do with it uh but it deserves a lot of attention which is it basically does a pattern type of tests where you have to do uh you know one standard one is you're given three things and you have to do a fourth one that that kind of thing you have to understand the pattern here and for that it really simplifies to um so the interesting thing is he's trying not to achieve high iq he's trying to achieve like pretty low bar for iq things that are kind of trivial for humans and they're actually really tough for machines which is seeing playing with these concepts of symmetry of counting like if i give you one object two objects three objects you'll know the the the last one is four objects you can like count them you can you can cluster objects together it's both visually and conceptually we could do all these things with our mind that we take for granted the object-ness of things we can like figure out what uh spatially is an object and isn't and we can play with those ideas um and machines really struggle with that so he really cleanly formulated these iq tests i wonder what like uh that would equate to for humans with iq but it'd be a very low iq uh but that's exactly the kind of formulation like okay we want to be able to solve this how do we solve this and he does it as a challenge and nobody's been able to um it's similar to the alexa prize which is amazon is hosting a conversational challenge uh nobody's been able to do well on on his but that's an interesting uh those kinds of tests are interesting because we we take for granted all the the ability of the human mind to play with concepts and to formulate concepts out of novel things so like things we've never seen before we were able to use that i mean that's i've talked to a few people that design iq tests sort of online they write iq tests and i was trying to get some questions from them and they they spoke to the fact that we can't really share questions with you because part of the um like first of all it's really hard work to come up with questions like it's really really hard work it takes a lot it takes a lot of research but it also takes a lot you it's novelty generating you're you're constantly coming up with really new things and um part of the point is that you're not they're not supposed to be public that they're supposed to be new to you when you look at them it's interesting that the novelty is fundamental to the hardness of the problem at least a part of what makes the problem hard is you've never seen it before right that's called fluid intelligence as opposed to what's called crystallized intelligence which is your knowledge of of facts you know things but can you use those things to solve a problem those are two different things do you think we'll be able to because we spoke and i don't want to miss uh opportunity to talk about this we spoke about the neurobiology about the molecular biology of intelligence do you think one day we'll be able to modify the biology of uh or the genetics of a person to uh uh modify their intelligence decrease their intelligence we started this conversation by talking about a pill you could take do you think that such a pill would exist metaphorically i do and i am supremely confident that it's possible because i am supremely ignorant of the complexities of neurobiology and so i have written ignorance is bliss well i have written that the nightmares of neurobiologists you know understanding the complexities this cascade of events that happens at the synaptic level that these nightmares are what fuel some people to solve so some people you have to be undaunted i mean yeah this is this is not easy look we're still trying to figure out cancer yeah it was only recently that they figured out why aspirin works you know i these are not easy problems but i also have the perspective of the history of science is the history of solving problems that are extraordinarily complex and seem impossible and seem impossible at the time and so one of the things you look at at companies like neurolink you have brain computer interfaces you start to delve into the human mind and start to talk about machines measuring but also sending signals to the human mind you start to wonder what that has uh what impact that has on the g factor modifying in small ways or in large ways the functioning the uh the mechanical electrical of chemical functioning of the brain i look at everything about the brain there are different levels of explanation on one hand you have a behavioral level but then you have brain circuitry and then you have neurons and then you have dendrites and then you have synapses and and then you have the the neurotransmitters and the presynaptic and the postsynaptic terminals and then you have all the things that influence neurotransmitters and then you have the individual differences among people yeah it's complicated but 51 million people in the united states have iqs under 85 and struggle with everyday life shouldn't that motivate people to take a look at this yeah you know yeah now but i just want to linger one more time that um you have to remember that the science of intelligence the measure of intelligence is only a part of the human condition the thing that makes life beautiful and the creation of beautiful things in this world is is uh perhaps loosely correlated but is not dependent entirely on intelligence absolutely i i certainly agree with that that's so for anyone sort of uh listening i'm still not convinced that um sort of more intelligence is always better if you want to create beauty in this world i don't know well i didn't say more intelligence is always better if you want to create beauty i just said all things being equal more is better than less that's all i mean yeah but that's sort of that i just want to sort of say because a lot to me one of the things that makes life great is the opportunity to create beautiful things and and so i just want to sort of empower people to to do that no matter what some iq test says at the population level we do need to look at iq tests to help to help people and to also inspire us yeah to do to take on some of these extremely difficult scientific scientific questions do you have advice for young people in high school in college whether they're thinking about career or they're thinking about a life they can be proud of is there advice you can give whether they're in the they want to pursue psychology or biology or engineering or they want to be artists and musicians and poets i i can't advise anybody on that level of what their passion is uh you know but i i can't say if you're interested in psychology if you're interested in science and the science uh around the big questions of consciousness and intelligence and psychiatric illness we haven't really talked about brain illnesses and what we might learn from uh you know if you are trying to develop a drug to treat alzheimer's disease you are trying to develop a drug to impact learning and memory which are core to intelligence so it could well be that the so-called iq pill will come from a pharmaceutical company trying to develop a drug for alzheimer's disease because that's exactly what you're trying to do right yeah well what will that what will that drug do in a college student that doesn't have alzheimer's disease so i would encourage people who are interested in psychology who are interested in science to pursue a scientific career and address the big questions and this you and the the the the most important thing i can tell you if you're going to be in kind of a a research environment is you got to follow the data where the data take you you can't decide in advance where you want the data to go and if the data take you to places that you don't have the technical expertise to follow like you know i would like to to understand more about molecular biology but i'm not going to become a molecular biologist now but i know people who are and my job is to get them interested to take their expertise into this direction and that it's not so easy but uh and if the data takes you to a place that's controversial that's counterintuitive in this world um no i would say it's probably a good idea to still push forward boldly but to communicate the interpretation of the results with skill with compassion with uh with with a greater breadth of understanding of humanity not just the science of the impact of the results one famous psychologist wrote about this issue that somehow a balance has to be found between pursuing the science and communicating it with respect to people's sensitivities the legitimate sensitivities somehow he didn't say how somehow somehow and this is part of that sentence somehow and balance is left up to the interpretation of the reader let me ask you said big questions the biggest or one of the biggest we already talked about consciousness and intelligence one of the most fascinating one of the biggest questions but let's talk about the why why are we here what's the meaning of life oh i'm not going to tell you you know you're not going to tell me this is very i'm going to have to wait for your next book the meaning of life you know uh we do the best we can to get through the day and and then there's just a finite number of the days are you uh are you afraid the finiteness of it do you think i think about it more and more as i get older yeah i i do uh and it's one of these human things that it is finite we all know it um most of us deny it uh and don't want to think about it sometimes you you think about it in terms of estate planning you try to do the rational thing right sometimes you it makes you work harder because you know your time is more and more limited and you want to get things done i don't know where i am on that uh it is uh uh just one of those things that's always in the back of my mind it's as i don't think that's uncommon well it's just like g factor intelligence it's a hard truth that's there and sometimes you kind of walk past it and you don't want to look at it but it's still there yeah yes you can't escape it and think about the g factor in intelligence is everybody knows this is true on a personal daily basis you if even if you think back to when you were in school you know who the smart kids were you know when you are on the phone talking to a customer service representative that in response to your detailed question is reading a script back to you and you get furious at this and you and have you ever called this person a or wanted to call this person a you're not listening to me everybody has had the experience of dealing with people who they think are not at their level it's it's just common because that's the way human beings are that's the way life is but we also we also have a poor estimation of our own intelligence we have a poor and we're not always a great this our judgment of human character of other people is not as good as a battery of tests we there's there's there's that's where bias comes in that's where our history our emotions all of that comes in so you know people on the internet you know there's such a thing as the internet and people on the internet will call each other dumb all the time and um you know i that's the worry here is that um we give up on people we put them in a bin just because of one interaction or some small number of interactions as if that's it they're hopeless that's just in their genetics but i i think no matter what the science here says once again that does not mean we should not have compassion for our fellow man that's exactly what the science does say it's not it's not opposite of what the science is everything i know about psychology everything i've learned about intelligence everything points to the inexorable conclusion that you have to treat treat people as individuals respectfully and with compassion because through no fault of their own some people are not as capable as others and you want to turn a blind eye to it you want to come up with with theories about why that might be true fine i would like to fix some of it as best i can and everybody is uh deserving of love richard this is a good way to end it i think um i think he's getting warmed up here i know um i know you can go for another many hours but uh and to respect your extremely valuable time this is an amazing conversation thank you for um for the teaching company the the lectures you've given uh with the neuroscience of intelligence just the work you're doing it's a it's a difficult topic it's a topic that's controversial and sensitive to people and to push forward boldly and in that nuanced way just thank you for everything you do and thank you for asking the big questions of intelligence of consciousness well thank you for asking me i mean there's nothing like good conversation on these topics thanks for listening to this conversation with richard heyer to support this podcast please check out our sponsors in the description and now let me leave you with some words from albert einstein it is not that i'm so smart but i stay with the questions much longer thank you for listening and hope to see you next time