hello everyone and welcome back to conversations with Tyler today I am chatting live with Greg Clark the economic historian I think it's fair to say that Greg is the most interesting and most influential economic historian of the last 20 years his book from 2007 A Farewell to alms presented a new
theory of economic growth human progress and the Industrial Revolution I end up as one of the blubbers and I called it as I wrote In The New York Times the next Blockbuster in economics his book after that the Sun s so n Also Rises surnames in the history of social
Mobility among other things argues that rates of social Mobility have been much less much more static much harder to change than many people believe Greg spent much of his career at UC Davis he is now a professor at the University of Southern Denmark and he has from Scotland Greg welcome thank you very
much great to be here I have so many questions about your work let me start with Mobility a point where I think we don't agree so I see Mobility across Freer societies as much higher than you do and I worry that you're treating Mobility too much in terms of relative ranking your kinti how
well is that predicted by your parents cantile or desile of income but if you just think of Mobility as having a much better and different life Freer life than your parents aren't rates of social Mobility just immense uh no uh the amazing thing is if we even go back to Medieval
England rates of social Mobility were just as high as they are now and I mean if you want to take these other dimensions of uh freedom of expression or uh social uh neighborhood that people were in again there's no evidence that that has in any sense improved now right I mean people are
just as divided in terms of the types of groups that they meet with as they would be 500 years ago and so I I really want to stick with this idea that in a society like England we have not in any way improved rates of social mobility in the last 300 years but that's focusing solely on relative rankings so if I
visit Liverpool and I look at Paul McCartney's home I know that's an extreme case but in Liverpool living standards are just much higher than they were earlier people have many more sources of Freedom it's true that where they fit into the desiles or other relative rankings maybe that hasn't
changed much but why is that the relative concept of social Mobility that's what I don't get um well it's it's absolutely the case that we're now 15 times better off than we were in 1800 um but it's still I think think a very important feature of society and one that you know people are obsessed
with is I'm not obsessed with it but but it turns out most people are right and I don't think they are in America I think they're obsessed with the absolute living standards they enjoy whether those go up or not and not so much about you know how the person in Mississippi
compares to Bill Gates I think it's exactly what people are are not obsessed with right well I I it's legitimate to say I see your question and I think it's unimportant right but I but I still think it's a fascinating feature of societies which is how are people between Generations moving between in
relative position within societies and and the other thing I would say is that you know that gain in material living standards is actually in some ways a lot less important than you might think I mean I've gone to you know Dr Johnson's house in London from the early 18th century
I'd be perfectly happy to move in and live in that house now with no penicillin no good dental care yes I mean there have been definite improvements in healthcare and other things electricity right uh but as say I mean in some sense you're just saying okay that I I want to concentrate on
growth right and I think that that's the The crucial element of society and if uh all of that growth goes to 10% of the society and not to the rest of Society I wouldn't care about that right uh whereas as I say it seems to me just in common observation that certainly the in
Britain where I come from that people do have this fascination with relative position in society and and the people are obsessed about who's going to the elite universities who are the members of parliament what are the backgrounds of these is the problem with Britain right it's an economy that has more or
less falling productivity since the great financial crisis it's far too stultified uh it's too status conscious and what we need to do is distract people from relative rankings and get just get them thinking about the absolute size of the pie well one of the reasons that I went to uh Denmark was
because of the Fantastic data that they have in the register data on people's social position in Denmark and in this new book that I just completed the draft of one of the things that's pointed out is social Mobility rates in modern Denmark are no higher than in Britain it's just this I believe
it's not correct to think of Britain as an immobile Society uh aren they both immobile societies Denmark people they go to the same high school they hang out they eat th those weird fish sandwiches and they they help each other out and you you know what you're born into more
or less determines how you your kids grandkids will do in Denmark but I think the D themselves would actually think of themselves as as a very mobile society and as a very open Society uh and and so so that's why as someone who's interested in societies I mean it it is fascinating to me that you
can change so much about social structure say between England and uh Denmark but somehow not change one basic fact which is just how connected are people to their parents in terms of their social outcomes and also how little influence social institutions seem to be able to have uh on that
connection and I actually draw from this a comforting fact which is to say meritocracy was achieved much earlier than you might have expected because what you would find in a truly Merr meritocratic Society is that the only things that really determine social position are going to be people's
genetic inheritance and Randomness and that status seems to have been achieved in England already by 1700 and so I actually draw kind of this different lesson which is that uh not only have we achieved growth in the modern world but we've also achieved meritocracy hundreds of years ago and I
I and I would think that a lot of people would regard that as a pretty radical Claim about the nature of modern society despite your skepticism let me give you a different reading of your work that probably you'll disagree with but let me get your reaction and this I call
Strauss plus Brian Kaplan so one way of reading Greg Clark is that he shows the re that social Mobility is quite high but the only path to social Mobility is geographically moving around so a simple example I think media and household income for families from India that have come to America it's $158,000
year which is remarkably high and whatever it was in India it was not close to that so they moved they're doing incredibly well when people move from say the rural South to the Northeast during the Great Migration they do much better that physical Mobility is what works and it's what
overturns these hierarchies and a lot of your data sets seem to be about times and places where not that many people are moving a lot but Mobility simply Works physical Mobility true or false absolutely and I agree that I mean and so that also clearly says that there are uh cultural and social kind of
constraints in society that allow some of them to be very high performing and some of them to be less well performing but then what's interesting and remarkable is that in this new manuscript we can actually Trace people who move from Britain to Australia Canada and United States and what's
interesting is that their material welfare increases very significantly but their relative social position doesn't change and somehow is preserved across these different societies and so the things that are kind of holding back societies as a whole it's very interesting that it doesn't seem to
affect relative social position right and so as I say that's why I'm a relativist and you're an absolutist but let me tell you if this further inference would be justified you're not a pessimist about the importance of environment you're a pessimist about the ability to reshape an environment when most of the people
are still around true or false uh yes I I say I the environment really matters it's just hard to change it so in that sense the weight you assign to genes is still up in the air because when we see the environment change a lot migration uh the effects matter a lot yeah but but it seems to me
that societies they come with different constraints but what's very interesting is that people's ability to operate within those constraints seems undiminished across different societies and the same factors seem to determine that and so I've actually done some work on Hungary under
communism where we again using surnames we can identify who were the descendants of the previous Elite and interestingly in things like admission to medical school it didn't change under the system of Communism the same Elites preserve themselves in the political sphere that Elite kind of
disappeared from Parliament for a while when uh the free market system was restored that Elite just emerged fully again into the political sphere and so what's interesting as I say is you can change the overall constraints on the society but it still is interesting that relative position seems to be
determined in some very kind of uh physics like way within different societies now how do you think about the social returns to more or less assertive mating say in the United States do we have too much of it to a little of it so if we had more of it you'd have say very smart or determined people marrying
those like them and you might end up with more Innovation from their children and grandchildren uh but you might also be messing with what you would call the epistemic quality of the median voter right so there's a straight off how do you think about that what side of the
margin are we at um so a sort of mating turns out to be uh a fascinating phenomena and uh and in this new new book we actually have records of 1.7 million marriages in England from 1837 till now and what is astonishing in England is the degree to which people end up assorting in marriage and so that
basically they're matching with people that are as close to them essentially genetically as their siblings in marriage and uh and it's really interesting because you could you people could mate in any kind of way right you could think I want the tallest person the handsomest person the youngest
person but for some reason consistently people seem to want to match to people who are close in social status now that doesn't affect anything about the average level of ability in a society but if it's consistently followed over Generations it will widen the distribution yeah of ability and are
we doing too much of that or too little of it in the United States it depends what your view is if you think that the engine of high-tech Society now like the United States is the top one or 5% of the ability distribution yeah then you would say the more assortative is meting
the more people will be in that extreme yeah and the greater will be economic growth yeah and so in the new book I actually speculate about was a sorted of mating in northern Europe a discovery of the late Middle Ages that actually then helped Propel things like the Scientific
Revolution the enlightenment the Industrial Revolution because as I say it's it's a remarkably constant feature of British side we can only trace it back to about 1750 the actual degree of assortative this and so so in that sense uh you can't have too much if that should view about how Society operates
right uh and and or at least we could have more of it right there might be some margin where youd but it does produce more inequality and so if you're worried about inequality in society you don't want disorder of meeting right I mean the one way to correct a lot of inequality would just be to have much
more random uh matching but one of the remarkable things about Denmark is education is essentially free until you're age 24 they give you subsidies for your living expenses for for child care provision it's all available they've compressed the income distribution quite
sharply there is this uh periodic survey of how well students do the Pisa uh measures Nordic countries have not reduce the inequality of Pisa measures compared to much more unequal societies like the United States and and so again it's just kind of interesting that high degree of inequality is still found
within these societies and it turns out that in Nordic societies people are mating again very strongly assortatively even now and so so that is the thing that you would worry more about is that there is this going to be this tradeoff between ass sort of made and the degree
of inequality in a society so let's say the Spaniards and others they come to the new world there's a lot of pairing off some of it is violent and coercive of course but a lot of it seems more random than what you might expect from Jane Austin's British Victorian society what's the implied prediction about what
results from that there's going to be less of sorti tative mating at least for a while right yes and and you would the implication would be you'll get uh just a narrow distribution see that it seems we see very high inequality in those societies well remember there's
potentially a difference between uh inequality based on things like wealth ownership and inequality in abilities or kind of educational potential that you would see within a society uh but definitely I mean there's clearly going to be this association between how assortative marriage is and uh how much
inqu quality you get so by the way we Neil cumins and I have a paper that just came out in plus one which is about hypergamy which is the idea that very common idea that women tend to marry up uh because men value physical appearance more than women do and that there's this tradeoff that exists in the
marriage market and interestingly for England going back to 1837 we claim that there is no hypergamy that essentially men and women end up matching in social status in marriage and it seems to be that it's just a complete dominance of social status in determining unions within this
Society for England I believe that you think it's true for most of the world it well the interesting question is is it it's definitely true for a bunch of earlier societies that the matching was much less tight and so for example there's a whole bunch of uh earlier societies where cousin
marriage was a very important form of marriage and the problem with cousin marriage for assertiveness is most people don't have a lot of cousins at the right age and gender and so it ends up that you have to marry a random cousin and it turns out that the modern British or or even the 19th century
British are matching much more tightly in terms of marriage than it would be the case if you just match to a random cousin and your you has cousin marriage been a big problem for the Arab Middle East that you lead you end up with something that's too clannish what I would say is it it if it's
systematically carried out it should lead to a kind of a reduction in the distribution of abilities within the society compared to the very assortative kind of northern European pattern or other patterns um I I honestly don't know whether it actually leads to these other problems
in terms of uh the clannishness of society right I mean potentially yes but it's not something that I've actually studied yeah it at least seems that today something about the cast system is finally paying off for India so from South India you have these incredible chess players right that's g-loaded uh
CEOs and Tech why is it that now the cast system in this one particular way is succeeding but in earlier times you don't see anything nearly is comparable like what has changed what's the environmental change and doesn't that mean like environment really really matters it's not all just genes oh no I
I in terms of overall economic performance I mean in my earlier book right uh Farewell to Arms it said there's essentially only two great problems in the economic history of the world the first is the incredible long delay in the arrival of the indust Industrial Revolution right right
and then the second puzzle is the incredible Divergence of societies since the Industrial Revolution where now you get these differences of about 50 or 60 to one in material living standards and this is really kind of Illustrated when you look at a society like India where
because of this cast system you had this super Elite the Brahman cast uh which preserved itself for many more than a thousand years uh Clearly Now you see when these people move to the United States who are the new Elite of the United States these are Indian immigrants the United States
who are who are kind of a super Elite within this society and then the stunning puzzle is why could none of that why did all of that Talent coexist with an incredibly stagnant Indian economy and stagnant even once it was opened up to the forces of the modern Market by the British and even once you had kind
of brought in kind of British civil institutions British legal institutions free trade free Capital markets low interest rates uh I mean this is one of the kind of stunning puzzles uh of the modern world and even though I write about that in that earlier book I have to confess I have no idea
why a society like that can remain so unchanged after the arrival of the British and not actually start transforming itself until the last 20 or 30 years I don't doubt the answer is complex but isn't part of it pretty straightforward and it has to do with State capacity so the British only
invested in a few kinds of public goods ones that would help them either trade with the country or defend it uh there was very little investment in human capital so in some ways it was nominally somewhat free but in terms of actual Market size and scale and building up of high trust
institutions uh the British were arguably even a negative influence right rates of growth are pretty low even under nou socialism India has a higher rate of growth why isn't that again far from a complete resolution of the puzzle but a pretty simple first order answer well it might not seem that the British
contributed much but if you even look at the kind of Anglo Indian group that developed in India that was massive I mean think about how big India is relative to Britain this was a massive potential entrepreneurial class in India and the British also had a policy that
allowed absolutely free migration of entrepreneurs into India so the Bombay textile industry something like 10% of it was owned by a Jewish Family that had come from Iraq this the suon family uh that uh you know that the British as I say welcomed these entrepreneurs uh they uh encouraged free
trade and so I think I I don't think you could underplay how significant an intervention that was by the British in that Society everyone is tending to judge the result the India now by the results but you know even KL Marx writing in the mid 19th century confidently predicted that the British
had created the next industrial Colossus in India and that that would kind of overwhelm the British in turn and it is one of the great puzzles of history is why India never developed under the British it just seemed that this was the path too much assertive mating that there's something to an O-ring model
where for a lot of production processes it's the weakest link the Le least well educated link uh the biggest source of social disorder that disrupts a town a village a firm for everyone else and in terms of the O-ring model India back then just wasn't doing well at all um yeah except you know I've I've
studied a lot in my earlier life on the Cotton textile industry and it turns out I mean that as I say that was one of the major industries of the 19th century you could run an entire cotton mill with three skilled managers and the tasks of people at the lower level there are extremely simple
don't require literacy uh in Japan were performed by 14 and 16 year old girls with high competence uh fantastic results uh and so you know now when we look at modern manufacturing processes they can often involve high levels of performance by workers and huge costs if
workers fail to perform form but it looked like in the 19th century that you had these kind of failure resistant techniques someone in a spinning Mill if they mess up the thread breaks more often right but that can all be repaired and you know it's all observable uh and so in modern high-tech
manufacturing you can see this problem but not in 19th century India right and so I still there a whole supply chain there's the networks and the search of getting the right people to those jobs so maybe it involves a lot of different moving parts and not just what's under
the roof of the factory so I think some Modern Indian you know very rich entrepreneur should should have a prize that would be devoted to someone who could explain why India didn't successfully industrialize under the British in the 19th century because it's one of those stunning mysteries of of
history and it's as I say it's easy for people just to say oh it's the the sclerotic English institutions it's the arrogance of the conquerors it's the cast system in India uh but none of that actually I mean if you look at the details none of that successfully explains uh what happened in India what
about the hypothesis there's something like akin to the Asian tiger mom to enforce it you need a network it's very hard to just do it on your own and for the network to be there you need many many moving Parts major social changes India back then maybe didn't have it today at least significant parts of
India have their own version of the Indian tiger mom who kicks the kids' butt across the room if they don't finish at the top of their High School class and that that's a social network it's determined by culture it's super hard to build up just by having a few British people arrive with ships and
finally we have it true or false well except as I say when the British arrived in India they the British were open uh the important thing that that people maybe have difficulty understanding about British upper class was it is an incredibly open upper class and they were absorbing uh people coming
from all different parts of the world uh the cun family for example ended up uh writing poetry against World War I and also as the chief Aid to the general fighting World War I uh and and so they actually and and they had absorbed into British iety lots of foreigners many
times before and so in India they were actually absorbing a lot of upper class Indians into British society and what I'm saying is to make the kind of Revolution that we would expect in India you don't need 10 million people you only need a couple of thousand it would seem to to lead India you know to Modern
economic growth and and that's what's so puzzling is that you know it's not you know you might explain all of this stuff but all you need is some deviant and so take an example of this Indian Mills underperformed British textile mills in 1940 there were 450 Indian textile mills there was not a single one
that achieved the average level of productivity of the English Mills how's that possible when you have this varied set of entrepreneurs varied set of people that you just cannot kind of match the the performance that's going on in this other Society I I remain puzzled by that say we look at some
other extreme example you know Korea South Korea so in 1960 it's maybe poorer than some parts of subsaharan Africa today it's a fully developed country I don't know what happened there but I know it's not a big genetic change something in the culture they got their act together and then they did great so
what's wrong with just assign these puzzles to culture doesn't mean we can explain them in the predictive sense India somehow developed a better culture South Korea certainly did that we pretty much know right wh why resist that kind of explanation well but see I'm not
resisting here right what I'm saying is I'd like to you know having now spent many years studying economic history have finally come to I think modesty and to say that look there are some problems that just defy any serious explanation that we make no progress with right but then say there
it turns out there are some other things where we can explain surprisingly well what's happening right and and so so basically what I'm saying is here's the things that you know why I turn to studying social Mobility is that here was something which actually showed this lawlike characteristic
and where you could actually understand the the processes and the logic of this and why I kind of turned away from studying things like why isn't the whole world developed is that it just seemed impossible to actually make progress on that because once you just say okay it's
some kind of cultural event then what are you going to say after that right but this is where I worry you're a bit too much of an economist if one insists on these very mono kinds of explanations everything testable measurable then surely so many things in human history are hard to explain but if we take a
more humani based view more pluralistic even just ask Korean people themselves they're full of explanations and they're all they'll often just say well we got our act together uh it doesn't satisfy many economists but maybe in some ways it is good enough if we just have a
broader sense in economics you know there's Ricardo there's Marx explanations are supposed to take a certain form maybe that's just our disease well in having written on the uh the history of the Indian industrialization in 1999 I dragged my spouse and three children on a femon uh tour of
India uh seeking to try and just by being on the ground there to see if you could understand anything more about why this economy which was still at that stage you know lagging enormously behind and I would actually we traveled on train all the time and we end up talking to Indians and it was interesting to ask
people you know why is India so poor and but it turns out that people have all kinds of answers but not they're easily testable as as false they we say oh it's the population we have too many people right uh and we know now of course that that actually is not going to make any
difference or it's the corrupt politicians or it's the education system stuff like that and so the problem with as I say this kind of pluralist IC open Humanities type explanation is it doesn't work it's time to get on board with the Scientific Revolution we can only explain things if we have these
mechanistic closed form empirically testable explanations otherwise it's just conversation if we take England when I read your book farewell to alms I took you to be ambiguous but when I reread that book through through the lens of your later papers it seems to me you're saying there was an actual
genetic change in English society because of who was marrying whom and having kids with whom and thus people you know saved more became more conscientious more forward-looking yes now if that was genetic rather than cultural why is it today when I go to England there's a lot I'm disappointed
by when it comes to conscientiousness I mean really quite a bit compared to say the rest of Europe and that to me suggests it was much more cultural than genetic the genetic change was probably small the cultural one huge because it hasn't persisted um I I mean the differences in
output per person in England compared to the rest of Europe are actually relatively minor uh and if you look at other kind of Productions like scientific production literary production other things like that there's no vast difference right but it's a slightly below a average mediocre
performance a bunch of stars in the south star achievements but if it were this General Trend through the population as a whole North England should be highly conscientious it doesn't seem to be that much compared to say the Netherlands at all well one of never mind Denmark right uh well well
two things I want to emphasize here so one is I think the processes that were operating in pre-industrial England reflect General processes operating in in northern Europe where all of these societies show this phenomena of survival of the richest uh going on hundreds and hundreds of years
before the Industrial Revolution we now we know very clearly that there are genetic differences between people at the top of the social ladder and people at the bottom and that that was going to change the underlying genetics of these societies and it seems to be as I say a general feature right
so that's so the first point so I don't think of England as being that different from these other locations right the the Industrial Revolution spread out much more across Europe than you might think there were accidental factors that propelled it to prominence in uh England in the new
manuscript what we're actually able I'm able to do is track the reproductive success of people since 1750 and there was a period from 1850 till the 1920 or 30s when an astonishingly low uh fertility emerged amongst upper classes in Britain and that was also compounded by very heavy
losses of the upper classes in World War I so 20% of men of that generation in the upper classes died in World War I but reproduction rates were at like one child per family or one and a half for 50 or 60 years years in the late 19th century amongst this group and so the relative size of the upper class in
Britain actually shrank dramatically in the course of this period and so that's one potential explanation of again why kind of British performance has been relatively uh larm since about World War I right because as I say it did go through this surprising and dramatic uh kind of transformation
socially where you really losing uh a lot of this uh upper class and by the way one interesting thing was how few of this upper class actually ended up marrying in this period it so it was somehow a kind of renunciation of marriage and of family uh at that time and and kind of puzzling
right and it doesn't it hasn't persisted I mean now in Britain fertility is pretty neutral between upper class and lower class but there was this 60-year period and that's associated with quite a dramatic decline of Britain's kind of Entrepreneurship and Leadership uh in the world economy and so there is this
kind of intriguing possibility that this actually was an important kind of historical event but the genetic perspective doesn't it imply that societies close to malthusian margins should actually become more and more conscientious over time because just to survive you've got to take care you know
of whatever savings you have and that that trade should evolve but just casual empiricism doesn't seem to show those societies as being more conscientious um but here's one element of casual empiricism so if you look in modern economic competition we can kind of rank
societies by how old they are so China it's extremely old if you go to other parts of Southeast Asia these are much kind of younger Societies in terms of settled agriculture and what You observe in Asia is that laborers exported from China to work on plantations elsewhere in Southeast Asia have become the
entrepreneurial class in all of those Societies in Indonesia and Malaysia in the Philippines uh and that somehow the history of different societies is still predictive of people are going to do in modern economic competition and the question would be you know putting it back to you you know
what kind of cultural explanation would there be for why that type of History would actually matter so much in terms of modern competition but one argument just would be that under the kind of the Anvil of the malthusian era these societies were just transformed more by
these selective pressures applied for thousands of years and that that then emerges in terms of kind of basic behavior of people in the society that makes them perform better even now the the most conscientious places Denmark being one example as you now live with uh they've been above subsistence for
quite a while the Danes had a somewhat mature nation state quite early as did England some relative form of stability uh markets with food supply and transportation Network again you could make a point about China but if you just test that point out of sample where are the conscientious
peoples it seems it's in the places the furthest from malthusian equilibria where selection pressures are the weakest uh now it it's true in Northwest Europe that living standards in the pre-industrial period material living standards were significantly higher the than it seems in Asia right and that
shows up in a whole bunch of ways for example people at higher living standards consume alcohol it's an expensive form of calories in Asia there's very little consumption of alcohol and that actually shows up now in terms of people's tolerance for alcohol uh again dairy products in
Europe they're widely consumed in Asia no again they're too expensive and that shows up again in people's ability to absorb uh milk um but because you're at this higher material standard doesn't mean to say that the Malian constraints are not still applying right and and so that there are relatively Rich
malthusian societies but they can still be societies where the conditions of reproduction are such that people are constrained that they will only reproduce successfully if they're above these living standards and that can be because of various social constraints about when people get married how
fertile marriages are uh and so as I say the the the fact that Asia that Europe was relatively Rich even and we can even extend this back to to this the uh the the the Stone Age in northern Europe uh where again skeletons from that period are very robust compared to somewhere
like Japan in the earlier period um that doesn't mean that these malthusian constraints didn't operate and one classic example of this is uh when people arrived in Tahiti that was clearly a malthusian society there's a bunch of people stuck in Island and you know with limited
resources and you were going to reach some kind of population equilibrium and you were clearly going to be under these malthusian constraints but it was materially quite uh a well resourced Society but but you still have these constraints and as long as you have these constraints it's possible then for
people who are doing better economically to produce more children and doing worse economically to produce fewer children this this is maybe a side point but it seems odd to me to think of them as malthusian when they have the greatest ability to transport themselves over
long distances of almost any society and they settle much of the South Pacific and the idea that Mobility gets you free land free supply of fish whatever they seem to have realized that better than almost anyone and the Europeans when they went there they didn't feel so sorry for the tahitians right oh no they
thought the Tans were were living incredibly well yeah so it wasn't malthusian of transportation and Mobility no no no but they were isolated and they had these very limited resources and it turns out why were living standards so great uh two things they had murderous internal Warfare that
disposed of a lot of people and the second thing is that they practiced very strong degree of infanticide and they were killing between a third and a half of all children born in the society and so it was a malthusian society but it turns out there are lots of malthusian societies where people live at
relatively High living standards well in what sense is it malthusian then that the regulating mechanism is not starvation seems almost by definition to make it not malthusian no no to to be malthusian it it just has to be a society where the regulate where there's going to be a positive
association between fertility rates and living standards right and where there's a limited supply of but that's a funny definition from alus I mean it's my definition clarky no no and and I I say this is a a widespread misinterpretation of malus I think is that malus is about low living standards right and so I
think uh my earlier book Farewell to Arms one of the actual Innovative elements of that book was to say let's take apart these two different elements of malthusianism and one is the element that you're forced to an equilibrium where the birth rate equals the death rate but the second is that that
equilibrium does not necessarily imply relatively low living standards and the way this shows up is after the black death in Europe which increased mortality rates living standards in somewhat like Britain in 1450 were not again equal till the end of the Industrial Revolution right but you
could tell this was a static population in England at that period uh there were tiny numbers of people there were made less than 2 million people in England by 1450 uh and but it was a consequently a malthusian economy but an incredibly Rich malthusian economy uh where people
when they talked about their diet they talked about the daily meat that they would eat and and so they really were living at high material living standards we can go back and look at the houses they constructed in that period people here in uh Arlington would be happy to move into some of these medieval
houses so under your current view is foreign aid to subsaharan Africa counterproductive and I'm not talking about corruption or siphoning it off those are clearly problems but just Aid as a brute abstract concept does it counteract itself through malthusian or what I would call clarky and
mechanisms um because I think you used to believe that I what there is uh there are societies like Malawi in subsaharan Africa where there is consistent economic progress but that progress gets eaten up in terms of population growth and so that living standards really have not
managed to increase for 50 or 60 years uh in these societies because they still depend very heavily on agriculture there's a limited agricultural area and better technology than induces more people uh how could you best help such societies uh it would be somehow by breaking that link between resources and
population so industrialization if it's possible to achieve would be fantastic in these societies and and the second thing would be limits on population growth and it looks like those limits are coming uh and that we are going to see such a transformation uh but there a lot of the say it is
public health right so more people survive more people live longer right that all seems to me to give them Better Lives it may not always show up in per capita GDP right but but even though there as I say there still is this kind of Quasi malthusian link between population and living standards
in these societies that doesn't mean to say that people wouldn't be better off if you give people more resources and so if you care about the the population in Africa and their living standards then there's nothing to say that Aid isn't a good thing in this case all that you can
say though is look a bunch of that Aid will result in more population growth and so it will undercut the ultimate effects of that Aid and it would be much more effective if somehow you could actually transform these societies so that they're not heavily dependent on limited agricultural resources now you wrote a
piece published in quette and you use the word hereditarian and you say I'm a hereditarian and that means a lot of redistribution of income is a good thing I'm oversimplifying your message but in so far as one as a hereditarian what are the policy implications of that oh well
I I think if once you recognize that a lot of our outcomes are actually the product of inheritance and are not mutable they're not changeable then that fits perfectly well with a society like that I like living in Denmark where there's a huge amount of redistribution effectively being done
uh and and so I think these things go together I mean you should recognize that you know a lot of things happen to us that we don't control there are accidents of our history our family history and that a good Society is one that doesn't magnify those differences between people but rather can seek to uh
compress them and one of the thing interesting is about Denmark it's stunning to me when I go there tax rates on people are so high but it's still a highly productive technologically Innovative society and so it's proving that you can have a surprising amount of kind of compression of income
differences and redistribution and still have a perfectly functional Society but isn't the implication in a way the exact opposite of that that if the way people can advance is by moving Denmark is pretty stingy with its migration policy and Denmark should have lower taxes
lower welfare to attract the higher quality immigrants say from South India and other places and they should be more open that would make them much more productive make the people coming from South India way way way more productive be good for the whole world because Denmark is closer at to the
technological Frontier we we see this with glp and it's exactly an argument against this kind of little closed we all went to high school together we're going to have a welfare state with high taxes approach right well I I must say that so there is a problem then in Denmark which is that in it's relies on
people not taking huge advantage of this welfare system which is very generous uh immigrants coming to Denmark have not responded in the same way and well you maybe you're taking in the wrong immigrants because if there's a welfare system and high taxes you're not selecting for the people who are
going to do the best unlike the United States which gets all these Indian CEOs because you can get richer here and stay richer right and well and and now actually in Danish politics there is a strong argument about what type of immigrants you want to attract and so throughout Europe in fact this has
become a huge issue but you've got to get rid of these high taxes to get the good ones um well that's a good question I mean not not I mean Denmark offers a lot of other uh good things in life though I must say the weather is not one of them uh but um it is it is actually
interesting yes how limited immigration has been from places like say Vietnam or uh India stuff that to places like Denmark uh because these immigrants would do would be very successful within this Society um and the more the native Danes are below replacement fertility the more urgent it is that you lower
taxes and attract the best migrants I would think so you should just be like a fullscale classical Li low tax regime yes you need a safety net but not too much because that will attract the wrong immigrants people that come to America they know they've got to make it on their own right and that
attracts on average the right immigrants yeah but but you could see every day in Denmark the benefits of having so unskilled workers earn much higher wages than they would in the United States uh people can live at a decent living standard I mean I'm living in California
part of the year and it's just shocking the number of homeless people there are everywhere right within a mile of my house there are people living homeless in California and that just doesn't exist this in Denmark and so I understand perfectly the Dan desire to to preserve this but the other problem
the Danes have is there's only 5 and a half million of them they cherish their culture their history and stuff like that and they you know one of the things they would fear about immigration is that already you know if you walk in the streets of Copenhagen the majority of people are
speaking English to each other and so the other thing I think is that would limit immigration to Denmark is that people really do have this cultural identity and one of the things that they wanted to insist was that immigrants actually have to assimilate uh and it's actually for that
right and it turns out it's perfectly possible for someone like me to not assimilate and speak English in Danish Society um and and so it is a kind of an an intriguing issue though about whether should we become more free market so that then we could have a different kind of attractiveness to to different sets of
immigrants right after you moved to Denmark Southern Denmark what was the biggest surprise for you uh um I was surprised at how kind of communitarian Danes were uh so at the University I'm at every Friday they gather in a lecture room to sing songs together right and uh also you know there's an annual
Christmas party and the university they have 4,000 people eat dinner together at the University I was actually surprised at that kind of sense of community that for you was that fun or stifling oh no I like it I mean I I appreciate it uh like you do it are you there singing I don't
go to the singing but the other thing Danish right that was my first surprise the second thing that surprised me was how committed Dan were as drinkers I'm shocked that these are the things that surprised you and and so in the town I'm in there's actually a pub that opens at 10: at night and stays
open till 8:00 a.m. in the morning and and Dan are not the most talkative people in the world and my thought is what are they doing all night at this PB uh you know that uh and so I as I say I was just surprised uh at that because I I I think of you know in other respects by the way Dan are super
healthy their gyms are open all hours there are people in there exercising all the time and and they do very well so I was surprised though at how much they drank and then uh secondly at at their the the kind of residing sense of community and so they have laws in Denmark for example try to prevent
Germans from actually buying Seaside property in towns where you actually have to live in the property all year uh and so I appreciate you know I I come from Scotland and so I appreciate uh the kind of the problems of kind of small societies trying to still remain kind of
culturally distinct in this modern world how optimistic are you about Scotland today um I actually I've seen the data and the north of England is in terrible shape but interestingly Scotland is doing much better and one of the things is uh what's interesting about Scottish
Society is when I go back there now I seem to them completely like an American americ but I meet all kinds of people who are completely non-scottish in origin who have become culturally completely Scottish and so my uh niece got married there to a guy who's Chinese and his best man was Vietnamese and they
were all dressed in kilts and they had bag pites playing and so culturally it's amazing that that people you know that the culture kind of continues in Scotland and in economic terms Scotland is actually doing uh uh pretty well uh and so as I say it's there's big subsidies right from south of England
without subsidies what's per capita GDP there well I mean I I did say that when Scotland was becoming considering Independence this would be like a parasite detaching itself from the host yeah because in order to keep Scotland within the UK they have been paying out these very generous subsidies so for
example in Scotland University education is free in England you have to pay for this uh and Scottish universities then actually uh have to charge English students for their education or else the English would be flooding across the borders into Scotland but it turns out under the EU the Germans could go for
free because the EU treaties actually said you can't discriminate against people from other countries but you can discriminate from people within your own country and so uh I agree that these uh but but my hope is that Scotland will remain part of the UK and will continue
to draw subsidies from the UK treasury uh and and as see it seems to be doing fine why are public health indicators so bad in and around Glasgow like there's some of the worst in in the developed World maybe the very worst so this actually was interesting when I was
writing my uh second book I wanted to illustrate this with a picture because GL go has some of the lowest life expectancy of of anywhere in Western Europe some parts of Glasgow within a few miles of where I lived in Glasgow and so I thought oh that's fine I'll go to Google Earth and I'll get a picture
of the squalor of Glasgow and it turns out it doesn't exist that no there squ Glasgow I to Glasgow no no the the subsidies and everything else are so generous that I couldn't find genuine squalor in Glasgow right New Jersy boy take you on a tour not compared to California right and so
in the end I had to actually use this kind of slightly fake picture which was sh squalor but it was because it was a building that was going to be demolished uh and but what is amazing is that within what is relatively decent material conditions people live these lives which
you know are ones of were you know terrible health conditions uh lots of people unemployed and again it's it's kind of hard to understand it can't be genetic right because it's fairly recent um so it's cultural no culture has this big huge influence but there's there's been a lot
of selective migration in within the UK and so this new book says the growth of the South and the decline of the north is all attributable to self selection within Britain and so Glasgow where I come from has had a huge amount of outmigration and out migration I mean it tends to be people with more Talent
ability stuff like that are the ones who are on the move and so you know what you're actually seeing I think a lot of that is uh uh this kind of selective migration of people though I must say so my my sister uh trained as a doctor in Glasgow and when they interviewed patients they were actually trained to
ask them well how much do you drink per day 10 pints and people would say oh no doctor only six and so you know it it really you know so that in some sense you might say well that's some kind of cultural hangover in terms of uh people's attitude to things like drinking and
exercise and vegetables and what's your take then on Modern Ireland because there's incredibly High rates of out migration and I don't just mean the Potato Famine just Irish going to Liverpool right America Australia all over you look at Ireland today it it doesn't seem selection is that important
their education level is the highest in Western Europe health indicators income whatever test you want to run they just seem like normal Ireland yeah the selection there hasn't mattered or what should I infer well so it turns out even though I I live in Scotland all of my family is Irish right okay now we're
talking same here and so so I've thought about this the whole selection issue uh but the interesting thing is so my uh co-author Neil cumins has a paper that just came out I think or just coming out about the Irish in England which argues that there was significant negative selection to
the Irish who actually moved to England and that the Irish within England even over the course of 150 years have remained a lower class in English society particularly those who move to the north of England right and and why negative selection in this hypothesis because the ones who are about to starve
uh I think one argument was the the kinds of jobs that were available in the north of England favored people who were unskilled right and so again in Scotland what were the Irish doing coming in they were working the steel works the coal mines uh scrapyards and stuff like that
I mean it was kind of heavy industry that was attracting these migrants and so one argument has been actually that the migration out of Ireland has actually not been particularly positively selected now in this new book I do actually look at migration from England uh to other countries and
interestingly so English migrants to the United States are the least positively selected uh but for other countries like Australia and New Zealand they are being positively selected but that's more than counterbalanced in England by immigration of skilled people into England right and so basically
England is constantly been refreshed by migrants from Europe who are highly skilled uh and so so so the the the process of migration is quite complex and so again the the question I had in Scandinavia was look Sweden and Denmark and and Sweden and Norway not so much Denmark lost huge fraction of their
population in the 19th century to migration how can these countries be so highly performing now right but again it turns out the evidence is that migration was actually negatively selected in Scandinavia if I go to North Dakota which is full of Scandinavians they're doing fine their
indicators are great they sort of look feel and act a bit like actual nordics demographically it doesn't feel like negative selection and it turns out so in again in the the book uh uh On The Sun Also Rises you can examine uh just looking at surnames different groups within us society and
basically all kind of European groups within the United States look very average right and so I think what was happening was that there wasn't really particularly strong selective pressures on migrations uh out of Europe you do see that uh people who came from Quebec uh French speakers from Quebec
are an underclass in the United States and that somehow there was some kind of negative selection of people from from that background but basically Europeans in the United States now are are very much people of European descent are very much average right and then the New
Elites in the United States are Chinese uh particularly Indians the Jewish population and stuff like that where there is clearly some kind of very strong positive selection going on but it seems like the 19th century migration was not so selective and so my sense for Ireland would be whatever the forces
driving migration in Ireland where maybe it actually was was either neutral or even negatively selected some of the immigration from Ireland do you have a sense for Latin America I I unfortunately don't know I know uh a different set of them go to Spain than to the US I'm not sure how it
all pays out but if you look at migrants from uh Latin America to the United States the further away the country is from the US the better they tend to do and so the more positively selected they the distance from equator growth hypothesis predicts that too right oh right that would also be yes but uh so I
think it tends to be if you're coming from places like Chile something like that coming to the United States I think it tends to be quite strongly uh positively selected yeah before we move to questions I'll just note Greg is uh in the process of producing a new book I
believe the title is for whom the bell curve TOS genetics and social life in England 1600 to 225 before I turn over to the crowd would you like to just say a few words about your next book I know you've covered some parts of it already uh yes so so the next book has been unfortunately 10 years in production
because uh it depends on assembling this very big database detailed genealogy of people over 300 years in England and I was really kind of motivated by this question of to what extent does genetics actually determine social outcomes and this book does a detailed study of all the predictions of a
genetic model right and so it looks at things like does birth order match matter does gender matter does your mother better predict your outcomes as compared to your father does family size matter if your parents die does that influence your life course what about your grandparents can they interact and
the conclusion in all of these studies is we're mainly the product of our genetics and Randomness and Randomness is a huge component as well but and that's why I say amazingly we seem in Sly like England for 300 years have largely lived in a meritocracy because what would be the
characteristics of meritocracy it would be a society where genetics and Randomness would be the only forces that really mattered uh and so that's what the new book then is all about and and one message to this is don't spend a lot of time with your children it doesn't matter Great Clark thank you very much
for questions there is the mic please do not block the camera and first question yes please I have a number of questions but I can U constrict the I'll start with see most important ones um so your your price your wage price Series in a farewell to alms takes a very barebones uh view of
what should be in the consumption uh basket you know so food you know housing clothing and then that's it right and so you have a very low estimate uh of of living standards but other more expansive uh like definitions like like moir's come to very large increases in
income uh from like time of Hastings to uh beginning of the Industrial Revolution and so I guess like do you have a philosophical reason for taking a very narrow construction and are you concerned that if you took that same very narrow construction uh into the present day you would arrive at clearly
absurd results like we have barely improved in living standards over time uh yeah so this is uh you know when you you construct these living standards series you just have to look at what people actually consumed right and so consumption of things like books in Europe in 1400 would be 0.1 of a percent
right and so if you were to take someone with our or Tyler's tastes for example and construct a cost of living index for him it would show radical transformation occurring actually in the 15th century when books became 12th of their price uh and books would be an important
component of his living expenses but that series is actually constructed for the average person in England and and what happens then is that you really don't see much kind of technological Advance on these typ typ of indices in in Europe because the advances that are occurring and they're quite significant
are about tiny shares of consumption and that's just a a general problem that if we wait economic uh technological change in economic terms there's this tyy of the majority which is what do the majority want to consume that's determining what the measured rate of technological Advance
would be and so that's one argument about again why the Industrial Revolution seem so abrupt is that there had been a lot of earlier technological advance but not in the Commodities that the average person consumes and what was unique about the Industrial Revolution was that finally something like clothing
now gets this huge advance and that then kind of transforms the economy so that's why that series was done that way next question thank you very much for stopping by um I want I was struck by your example of the it was the Chinese fiance that was wearing the Scottish kilt alongside
uh his Vietnamese um one of his best men best man yes yes um it ties into the point you made about assimilation in your work what factors encourage ass simulation into culture into like Norms of the Home Country versus the opposite and do you think that's related to
economic incentives or is it more about culture thank you um so I'm impressed I as I say I've studied a lot about the upper class in Britain and when you see the history in this genealogy of these families you have like Jewish families arriving in Britain 1800 where their descendant becomes a bishop in the
Church of England within three generations and so you do see this as I say surprising kind of plcity but other families remaining kind of firmly Jewish but in other ways is becoming highly English and a nice example of that is in 1685 the hugenots were driven out of France and they arrived in Britain they
constituted about 1% of English population at that stage you can see them within one or two generations completely culturally assimilating and you can see that in the names they called their children and in the women that they married or the men that they married right and so you
actually see as to say this complete kind of and Rapid kind of cultural assimilation and then a movement into the elites of British Society where they amazingly the descendants of that group are still four times more likely to go to Oxford or Cambridge than the rest of people in English society even though
culturally 200 years earlier they lost any kind of distinctiveness and so so as I say I'm impressed when you see something like Britain how rapidly that assimilation occurs and even in my own family so my grandfathers were both born in Ireland uh we were in Scotland as Irish
Catholics we didn't mix with Protestants we didn't uh talk to Protestants we had all kinds of weird theories about Protestants and the kind of joyless Life uh I have a brother who married woman who's Protestant his children are functionally completely Protestant right and so you
see this kind of even in this period that by moving into kind of the upper class in Scotland which is heavily Protestant effectively you see that assimilation and so what I am impressed is just how rapidly people can typically assimilate into other societies except I think in cases where people aren't
succeeding economically and socially and and that then becomes this barrier uh to assimilation but people who are successful within new societies it's just astonishing how plastic As I say the culture of different societies is uh and and as I say I never thought I would
go to a wedding in Scotland with people wearing Kilts right because that was completely not the culture that we came from yeah hello thank you so much for coming and giving the talk it was an honor to listen in person I learned a lot lot from your research um being said that I I really uh liked the example in
one of your research where you used the last name Smith and how long it took for somebody named Smith to get to like places like Oxford it was about 200 years and I loved that research method but also the conclusion is a bit deterministic it's kind of how do you manage that social Mobility so I think
on that I'm a bit more on the side of Dr C where International Mobility might have a higher rate of results than uh the examples in your research and as far as I know the research is mostly from the Anglo world uh within mobility within Anglo world or Europe to Anglo and the other ways around and um I we
use the example of India and I think the cast system is unique there but what about the countries that are similar in terms of base of living standard um I'm from Bangladesh like places like Bangladesh or uh Sri Lanka also in recent research in IM ation we see in the United States immigrants from Mena
Orion are very um very successful so do you think if we change the directions of migration and basis of living standard from these donor countries um if will the results look uh more optimistic and the second part of the question is um there is a research done by johanes
Hoffer also a Nordic Economist and he has a project where he takes students from Uganda so we can get around the pre-selection problem and he um funds them to come to Germany to study so maybe uh policy prescription wise do you see some benefits in this kind of solution to get out of that
deterministic trap thank you so so let me talk first about the determinism trap and so this is a there's a fundamental kind of philosophical issue here which is I you know I've spent a lot of time in economics and economics really is a dismal science in the sense of how little economics has
achieved right and how little we can predict about economies or about the future of economies and so one of the stunning things about social Mobility is how deterministic at the group level that this is and how in the English data You can predict what will happen to people 300 years later based
on their position now right and I think of that as a kind of a stunning kind of uh gain right um maybe unlike Tyler here uh and and I think of that as the only path forward and and as I say what I was stunned by was in terms of social Mobil Mobility how much mechanical deterministic structure you had in
societies right now I secondly agree that um people moving between societies is an enormous source of economic gains and economic Mobility the relative position though seems to very substantially move with people when they move across societies and so and I agree that it also has these very important policy
things that we have to think of which is if America takes in more immigrants it will benefit the world at no cost right uh and and so that we we you know mo you know a lot of substantial gains will be made by moving people around in the modern world and that that's something
we should think about in terms of thinking about policy in in different countries uh and so I agree there that you know that that substantively there's not a lot you can do within a society to change people's relative outcomes but there is a lot you can do for people by moving them from one
Society to another and that that's the area there that we should think about in terms of Economic Policy thanks a lot thank you uh I have some uh related questions on uh how you're measuring uh social persistence so the Persistence of social status is the rank rank uh correlation
over time which means that if there is error in measuring the status of somebody it tends to increase uh social Mobility because there's less correlation uh so are you concerned that the degree of air has changed over time such that it's uh higher in the 1800 for example than compared to today as some
like recent work on American inequality uh has has demonstrated and and secondly uh when you change when people are added to the population through immigration if they're for example say at all the bottom then it would tend to bias people's uh social Mobility upwards because now it's a the different people
in the mix so how do you account for that and how do your methods avoid this right so it turns out a lot of the the new book there's a whole section which says people have not thought about errors enough in terms of measuring social mobility and so one classic thing
is people typically if you go to Scandinavia the income correlation between parents and children or the education years of education correlation between parents and children is low implying that these are very high Mobility societies and the problem is that the errors involved in these measures so
measuring someone's education level by years of education is a very crude approximation right and it really tells you relatively little particularly in a society like Denmark where there's enormous access to education and huge subsidies of education and so a lot of the book is saying how do we correct for
these errors and it turns out that's what happens when you do correct for these errors what you find is much much lower rates of social mobility and also that it doesn't vary between Scandinavia and England now or England in the 18th century okay and and I think you know in Social Mobility
studies that that any kind of report that isn't taking into account that all of these are very partial and imperfect measures uh is just not telling you a lot about the true nature of uh social mobility and so that was the the first point the second point was well what about ad mixtures within populations and
how that would influence measures of social Mobility fortunately uh for most of these societies these would tend to be relatively small changes because it's a small share of the population in any generation that is now coming uh a new um but you do see now in England a kind
of dramatic transformation where the white British now are the lower class of English society there's emerging and very substantial new upper classes which are Africans uh bangladeshis uh pakistanis and particularly uh Hindu uh Indians and Chinese uh and as I say it's it's an an
amazing kind of transformation of a society by immigration and because of fertility differences where immigrants tend to have much higher rates of fertility a very substantial fraction of 15y olds now in a society like England are from these other Origins but actually it's been an
enormous benefit to English society and but it would have influence things like trying to calculate social Mobility rates when you have all of these new groups kind of arriving in the society and actually being uh very uh successful uh and but I agree but that's actually
really a very much a phenomena of post 1960 or something like that in Britain thank you Professor Clark it was a lot of fun um what do you think are the practical implications of your work for finding a spouse in the modern world I'm not sure uh what to advise you I can tell you that uh I met my wife
when we were both graduate students at Harvard I was the first man she met at Harvard so so maybe she wasn't particularly selective in terms of um I mean what what can you say I mean you see a general pattern do we know that that pattern makes people happy maybe everyone with highly assortative
marriage is actually unhappy and if instead they had chosen a spouse on on grounds of you know romance or something else like that uh they would be uh much better off uh all I can say so I can't give you any advice on marriage all I can do is say I can predict the kind of person that you're going to marry thank
you I wanted to ask about a an ongoing debate between James Heckman and Raj chedy on the role of neighborhoods versus family composition so James Heckman believes okay family composition really matters listening to this talk you'd say maybe not and then cheddy says
that neighborhoods really matter and I'm wondering if you take stands on these things since it seems that there is considerable variation at the neighborhood level but then I'm told at the national level it all balances out so there's no variation over time I mean what a coincidence this would be in
social science so I just wanted to hear your thoughts on some of these technical recent matters thank you yeah so there is a chapter in the new manuscript which examines exactly this issue about does it matter what place you're born to in England because as I say the north is much less successful on every Dimension
uh education output output whether people are employed or not Health longevity it's bad somehow to be born in the north but with this kind of comprehensive genealogical database we know all about everyone's parents and stuff that and I can tell you that there's actually very little cost to
being born in the north right it's mostly still predicted overwhelmingly predicted from the status of your parents and it just turns out there are many more High status people in the south of England now one puzzle is it's this movement to the south of England of higher status people has been gone on
since the 18th century and I don't actually understand why did everyone want to move to the areas around London and the south of England from such an early date in Britain so even in the industrial revolution period the balance of migration is of skilled people out of
the North and to the South and the migrants from the south to the north tended to be much less skilled and so basically the story for England is there is this kind of process of selection and it turns out that that interestingly also occurs in other parts of Europe and
it's it's amazing that with you know modern markets and stuff like that that in almost every place in Europe you'll find high income areas and lowincome areas and and kind of endogenously developing but as I say as far as we can tell from this British data there isn't that much cost so I was uh born in a
mining Village in Scotland I like to think I escaped my background uh but you know uh empirically the the average person born in that mining Village is going to do do pretty poorly but there is this question is is it all just about family background or is it about the opportunities that people get offered
yep last question Nicholas um how do you if I believe your chosen mechanism uh for it transmitting over over time to be in fact genetics uh how do you reconcile the very low estimates of heritability from genomewide Association studies with the much higher estimates uh that come
from twin studies uh well these genomewide studies amazingly even with the you know something like now is it up to 4 million people that they have genotyped where they have measures of their educational outcomes still don't identify that well what the genetic basis of this is that we know exists
from these twin studies and uh and in some sense what it's saying is these studies are still we still have very imperfect measures even though they're identifying a thousand different Loi on the genome that are affecting educational outcomes we're still somehow not capturing everything that's
happening here and they've also studied whether it's it's combinatoric effects that really matter but I think they've largely been ruled out that it's mostly just the additive impact of what's happening at each particular location uh and so all I can say is that I mean it it has this weird implication
that you may need studies that are bigger than the whole of humanity to actually finally figure out what are all these genetic influences because there are such rare kind of uh uh permutations that are actually uh affecting outcomes and it also actually surprisingly means
that if you have very small population say uh Native Americans that you might not be able to do these kind of studies because you wouldn't have enough people to actually be able to say very much about say the genetic basis of illnesses or the genetic basis of height and other
things like that but it is a puzzle in that literature which is that even with this amount of data and even though knowing that there is this genetic basis that that is quite strong they still cannot actually find mechanically what the location of that basis is Greg Clark thank you again big can for Greg thank you