Genes, Romano-British history and bullshit: analysis of a dispute

In July/August 2017 there was a bit of ‘disagreement’ on the social media platform Twitter, with some right-wing users attacking the BBC over an educational cartoon about Roman Britain, because some of the characters were shown with a darker skin than others. Sides were taken in articles and postings by experts and others on the question of ethnic diversity in Roman Britain. This same issue has popped up again on occasions since.

Mary Beard, the classical historian, emphasised what is known about the diversity of the Roman presence in Britain, and came in for considerable abuse from the far-right.There was an intervention on the other side from Nassim Nicholas Taleb, the statistician, who made various assertions based on genetics. It’s not my purpose to discuss these arguments here: it does seem that both sides talked past each other to some extent, especially in regards to the meaning of ‘diversity’. You can find more about this here and here and here (and other articles).

There is just one particular point I am interested in here, and it arises from an intervention on Twitter from Taleb, which I responded to at the time.

@wmarybeard: this is indeed pretty accurate, there’s plenty of firm evidence for ethnic diversity in Roman Britain

@nntaleb: Historians believe their own BS. Where did the subsaharan genes evaporate? NorthAfricans were lightskinned.
Only “Aethiopians”, even then

@nntaleb: We have a clear idea of genetic distributions hence backward composition; genes better statisticians than historian hearsay bullshit

Trying to leave aside the left-right political positions and the racist motivations involved in the wider discussion, this particular argument seems to reflect an idea that supposed ‘hard science’ (in this case, statistical genetics) trumps ‘soft’ (history/archaeology). I do not want to get into discussion of ‘hardness’ and ‘softness’ here, but I shall try to analyse Taleb’s specific argument about genetic distributions.

There are three sets of data in this problem. One is the set of data on the genes of the living population of interest, and another is the set of genetic data on the historic (or prehistoric) population that the living population is being compared with. There is also another set of data: the written records, archaeological finds and all other items that comprise what Taleb dismisses as ‘hearsay bullshit’.

All of these sets have their own specific technical problems. The historical data certainly have problems of interpretation amongst themselves: dating of objects and authorship or precise meaning of documents, for example, may be uncertain.

But collecting genetic data also has considerable technical problems: for example, obtaining reliable data from living populations is much easier than it is from fossils or human remains, as there are typically fewer remains than there are available living humans. Also the DNA from human remains may have degraded over time or been contaminated with other DNA, such as from microbes, and needs careful separation.

There is an additional problem with the data from both living and past populations: we have to be reasonably sure that the sets we have are representative of the populations they are taken from, since in neither case can we analyse the DNA of every individual. The genome of an individual is ‘data’ or an ‘anecdote’ to the same extent as a single archaeological find or written record is. It doesn’t tell us anything about the population until it is put into context with all the other similar data. This is a particular case where statistics is used: it is a mathematical tool to help us make a (probabilistic) estimate of the genetic composition of the population that our data sets come from. This is not an automatic process: it involves making assumptions and using the right statistical method, so it has its own issues and uncertainties.

We can think of the problem we are trying to solve here as a theory: how can we explain the genetic makeup of the modern population in terms of the genetic makeup of the past population at the period of history that is of interest? Looking at it this way, we can see that there is no ‘backward composition’ we can automatically use to derive one from the other, whether it uses statistics or any other mathematical techniques. The genetics of the modern population must depend on its history, as well as the scientific principles of genes. In the time that elapsed between the past and the present populations, we need to know what has happened to the population. Did certain groups migrate in or out of the population, was there mixing of different populations, was the population subjected to ethnic cleansing or genocide? These are questions that are very hard to settle, for example, to what extent did invading Anglo-Saxons displace the British currently settled in what is now England. Historians have good reason to believe that the Anglo-Saxons formed a new ruling class, and that some of the existing British were displaced by migration, but there is still dispute as to what proportions of the original population were killed or displaced.

So clearly we can’t ignore history here. The current genetic composition of a population is a result of both genetics and history. That history is part of the problem to be solved. Some of it will be attested by artefacts and documentation, some of it is purely hypothetical (and might be solved with assistance from the genetics). The point here is that the historical evidence cannot be dismissed: any theory, including reconstructing ancient populations, must reconcile all the relevant evidence, or it is simply inadequate. If it is contradicted by the evidence (and the evidence is not found to be defective), then the theory is false, and needs modification or replacement. The evidence here includes (at least) the available genetic data and the historical evidence, including written records and archaeological finds.

Note that I am not making claims about the actual history of Roman Britain here.  I don’t have the necessary expertise in the technical fields. I am simply trying to analyse the problem, to see why genetics is not in itself adequate to the problem, and the history cannot be dismissed. Solving the problem necessarily needs the technical expertise of the geneticists, historians and any others with relevant knowledge.

To see why the history is essential, consider the following scenarios (not an exhaustive list) that might happen to a population of interest:

  1. The population remains isolated from any other.
  2. A small number of immigrants arrives, they seize power and become the ruling class, and eventually merge with the main population through interbreeding.
  3. A large number of immigrants arrives and merges with the main population through interbreeding.
  4. A foreign power occupies the country, using troops from other populations, but remains largely separate from the main population. In the end it (largely) leaves.

All these scenarios will leave both different genetic traces and historical and archaeological data. Likely, given the inadequacy of the evidence, the problem will never be finally settled, as there will always be anomalies, gaps in the data and unsolved questions.


Statistics is a branch of mathematics. Strictly speaking, it is fit only for analysing distributions of pure numbers. Whenever statistics is used as a mathematical tool in solving questions about the real world, other restrictions apply. We are then not dealing with pure numbers but with physical entities (and the concepts we use to understand those entities). In the particular problem above, these entities include people and their genes. In the physical world, these entities are subject to other principles, including the human lifecycle and the physical processes of genetic combination.

Sadly, statisticians, however good they are at statistics, can lose sight of this fact, and claim authority for statistics that is simply not justified. A very good example of this is in the supposed debate over human-caused global warming, where statisticians have weighed in on the ‘sceptic’ side with statistical analyses that simply ignore the laws of physics. One statistician has called this ‘mathturbation‘. Climate measurements are not simply numbers, they are properties (such as temperature or carbon dioxide concentration) of physical entities such as air or oceanic water, and our theories about them are part of physics.

In trying to understand things that happen in the real world, outside mathermatical textbooks, you can’t ignore the technical experts and their knowledge: statistics may prove them wrong, but only when correctly applied to the subject data.

Nassim Nicholas Taleb

The involvement of Taleb in this debate was very strange. He seemed to glory in taking the part of extreme right-wing participants in (sometimes vicious) attacks on historians on Twitter. He derided Mary Beard’s academic credentials, and frequently calls experts in other fields ‘bullshitters’. Yet his claim about genes and statistics reproduced above is bullshit, where bullshit is the term for not actually lying, but giving the impression of having knowledge he didn’t actually have.

Taleb’s background is as a statistician and a trader on financial markets. Financial markets are about the nearest thing in the real world to pure numbers, and mistakenly thinking that climate data are in some way similar to markets has led many people into error. Perhaps this confusion applies to other areas as well.

Taleb also seems to have a very thin skin, and has blocked me, and apparently many others who disagreed with him, on Twitter.


About this #Karatbars #gold thing

Please note: this is not intended to be investment advice. For that, you should see a professional. This is intended to be a comment on hard sell and misleading information.

If you go to an event like this, for any scheme at all, it’s obvious that you should not enter into any legal obligation at the time, even if you are offered an incentive to do so. Go away, think about it, and research the offer extensively, including — especially — any warnings about or criticism of the deal. This applies to any similar scheme, not only Karatbars.

I went along with a friend to a meeting in London presented by (or on behalf of) a company called Karatbars. Karatbars sells small quantities of gold to the public, from 0.1 to 5 grams, in fancy packaging that looks like credit cards, medallions or polymer banknotes. These were presented at the meeting as an investment. In addition, the company offers a range of ‘affiliate’ schemes, in which members of the public can make money by introducing others who buy the products. My friend asked me to give feedback on what I heard, so here it is.

The main speaker had, apparently, flown from Northern Ireland specially for the meeting in south London. He was a skilled and entertaining, not to say hyperactive, speaker and clearly knew how to engage with his audience. But it’s what he said that I shall comment on. And what he said was seriously misleading, even if there was nothing that could actually be called a lie. That’s how hard sell works.

First, he went through a spiel about how gold is ‘real’ money and cash and notes (not backed up by gold*) are not ‘real’ money. This is bunkum: if anything is ‘real money’ it is the legal tender of your country. This is what you have to pay your taxes in, and if someone owes you a debt, then you are entitled to insist they pay it you in legal tender. They may offer to pay you in gold (or coal or duck feathers or tickles) but you are entitled to refuse, and they cannot insist that you take anything but the legal tender.

Second, before coming to the real sell, he tried to make out that gold is much better than cash because gold increases in value while currency depreciates. There was a lot misleading in this, and I shall come to this later.

Third, the real sell was to get you to recruit other people to sell the gold on the company’s behalf, and here again the speaker was not honest with the audience..

Now here is the question you should ask yourself: if gold is better than the legal currency, why is the company trying to sell you gold in exchange for currency? Wouldn’t it be better for it to just hang on to the gold? After all, companies exist to make profits and their bosses usually want to get rich. The company, clearly, does not believe its own message.

So, let’s look at some of the points the speaker made, and the points he (significantly) didn’t make.

The Karatbars product is small amounts of gold in fancy packaging. Reportedly, this is much more expensive per gram than sales of gold bullion. There are a number of reasons  for this. There are the higher overheads of selling small amounts (this applies to any commodity), the fancy packaging costs money, and the company’s selling methods and commission schemes will also be a big overhead. So, if you are thinking of the gold as a profitable investment, then the price of gold has to go up a lot before you even begin to think of making a profit.

It may well be that a certain amount of gold is a suitable part of an investment strategy (this is not advice, remember). But gold is used by rich people as a hedge, and its price fluctuates by huge amounts. It’s likely that you will have to wait many years before you see a profit. In the meantime you will have the cost and worry of storing it and protecting it from theft and the danger of being mislaid. At least, as the speaker, claimed, it will survive a fire — if you can find the tiny amount in the debris of your house.

The speaker implied (flicking one of Karatbars’ banknote-looking products) that you could use it to settle a purchase. No, you can’t (in general). As I pointed out they aren’t legal tender, and the small print on the item is a disclaimer that makes it clear it is not legal tender. One of the problems of using gold as cash — why it’s better to use currency — is that it is difficult to establish the price of the gold at the point of sale. The ‘spot’ prices you see online are guide prices based on large transactions of gold bullion (including settlements of debts between sovereign states), and are not a good guide to the price at which you can sell a few grams or a fraction of a gram. (I see that Karatbars has a network of businesses who will accept the gold ‘banknotes’, but it’s a reasonable guess they will not be the cheapest vendors.)

The speaker missed out a very important point. He compared the value of currency after inflation with the rise of the price of gold over (say) 30 years. But that is VERY misleading. If you have any sense you would not keep your money in a sock for 30 years, you would invest it in a scheme such as a pension fund, ISA or something similar (after, I hope, taking advice).

I am told by an independent financial adviser that at present, even in these times of low interest rates, a realistic rate of return on a stocks and shares ISA is 4% per annum (your own experience may vary). Assuming that rate over 30 years, a fund of £100 would be £324 now. Looking at the gold prices over the last 30 years, using the price at the time of writing, £100 of gold would now be worth around £280, although you would probably not get as much as that if you sold it. Remember the price of gold is likely to fluctuate daily as well as over the long term. If you sold the £100 of gold in 2012 it might have been worth about £400, but if you had bought it in 2012 and sold it at the time I’m writing this, you’d have lost about a third of the value.

That is not taking account of other factors, such as possibly having to pay tax on your gains in gold and special tax exemptions for savings in ISAs and pension funds.

So taking all the above into account, it doesn’t look likely you will get rich on investments in Karatbars gold. But they know that, that’s why they don’t just try to sell you gold, they try to recruit you as an ‘affiliate’.

Many affiliate schemes are entirely legitimate, of course, and the speaker compared the Karatbars scheme to those of companies like Amazon, where you can get commission by advertising that results in sales. No problem with that.

But the Karatbars scheme goes a lot further. Unfortunately I didn’t get a picture of the screen, but the speaker’s schtick included a calculation that showed you could be earning thousands of pounds per week from recruiting a couple of people who would each recruit a couple of people, and getting commission from the sales made by the recruits. There was, of course, some small print that the speaker didn’t draw attention to. So, if you do this, you are not simply making money from gold, but from the packages that each recruit has to buy to join the scheme (although there is apparently also an income stream from commission on the gold they buy.). This is called ‘multi-level marketing’ or ‘pyramid selling’.

But there’s a serious problem with this scheme. In order to join any of the affiliate plans, you have to pay up front for a package. In the example, the speaker supposed that in  the first week you recruit two people, and you get a share of the cost of the package each one buys. Then in the second week each of these recruits two people, in the third week each of those four recruits two (8 in total) and so on. So the scheme means in the fourth week 16 in all have to be recruited to keep up the flow. Each time this happens, you get a commission.

In the 13th week, in order to match the model the speaker showed, you have to have 18,192 people in the scheme, all paying you commission. In half a year, to continue as before, the number of people in the pyramid below you will have to be more than the entire population of the UK.

So that’s not going to work. Of course, if you are an assiduous salesperson, you may well recruit lots of people, and make a decent income for a while. But eventually, the people at the bottom of the pyramid will pay out money but fail to recoup it. The people higher up have recovered their costs but their income dries up. The people at the top are laughing all the way to the bank – and it’s your money they are laughing over, not gold.

There is another disturbing aspect to this whole thing. The speaker showed a slide with a whole lot of different affiliate schemes, which were not individually explained. I suspect (but do not know) that these are used to lure people into putting more money in when they fail to make money at first: “it’s because you didn’t invest enough first time round, buy this more expensive package and you’re sure to make a fortune”, appealing to the addiction of gamblers.

I am not saying you should not buy Karatbars, it is a decision for you to make, but I am pointing out that there is a lot you should consider before making that decision, and a salesman will not give you all that information. One claim of Karatbars is that its gold comes with a guarantee of purity, and you should verify that to your own satisfaction.

Disclaimer: I have not looked in detail at Karatbars the company or its offerings; this article is based on the sales talk of a particular salesman on one particular occasion in August 2017. I note that the presentation of the company’s products on its website makes it look as if they are novelties, collectibles, gifts or give-away items for business promotion, and you might well choose to buy them for these purposes rather than regarding them as investments. That’s up to you.


* Up to the early 20th century, in many countries, all currency issued had to be an (empty) promise by the government to give you an equivalent amount of gold if you asked for it. Some people still think we should go back to that system. It would be pretty pointless though, because overwhelmingly most of the money in the country – what you have in your bank account or savings – is created not by the government, but by banks when they make loans.


Letter to MPs from a Remain voter: a plea for realism, tolerance and honesty

This is the text of a letter written by Richard Bronk, a Visiting Fellow at the European Institute of the London School of Economics, to two Conservative MPs, one a friend, with whom he was in correspondence. The letter (which has been anonymised) was written to foster a better understanding of how many of the 48% who voted Remain are thinking and feeling following the vote – and thereby contribute to efforts to bridge the dangerous chasm opening up between most of the UK’s great cities, universities and the young, on the one hand, and the new Brexit government on the other. 

Source: Letter to MPs from a Remain voter: a plea for realism, tolerance and honesty

Betrayal, and beyond

I don’t get this idea that “we should not betray the majority who voted Leave”. Or the idea that ”we should just leave the Leave side to sort out the mess they have created”. We are all in this together, including the youngsters who overwhelmingly voted to Remain and will be still suffering the consequences when many of the elderly Leave voters have died.

A lot of betrayals have occurred. We were all betrayed by the Government, which held a referendum that hardly anyone wanted, in the pursuit of a struggle between right-wing factions and an openly racist minority party.

The Leave voters were betrayed by Cameron, who promised the Government would act immediately on a Leave vote, and then didn’t.

The Leave voters were betrayed by their own side, who made promises they never intended to keep, and that would be impossible to carry out anyway. That had no plan. And made the campaign overwhelmingly about immigration, with a unmissable racist theme.

And the Remain experts, the ones Leave said to ignore, were proved right.

Whatever is done now, there are unpleasant things going to happen. If we leave the EU, the UK will break up and England (outside London anyway) will suffer more economically than it does now – and as a result there will be disaffected Leave voters. If we don’t, we still have a massive problem with an emboldened extreme right and disaffected Leave voters.

But undoubtedly leaving the EU will be worst. Don’t forget that, when we negotiate with the EU, they have experienced negotiators – the ones that we have for the last forty years paid to negotiate on our behalf as part of the world’s strongest trading bloc – and we shall be represented on the political side by the same ignorant, incompetent and corrupt politicians who visited this disaster on us.

The referendum was not binding on the Government. It is time for Parliament to assert its sovereignty, behave like adults for once, debate the referendum and the reasons for the results, and then (hopefully) reject the result once and for all. There are very good reasons to do so.

Then the Government should begin without further ado to try to undo the damage it has done to whatever extent that is possible. To reestablish full cooperation with our European partners. To investigate the economic circumstances that led to protest votes against the political system. To create a voting system that allows people peacefully and fully to reflect their concerns through Parliament. To end the economically illiterate and disastrous policy of austerity.