inversions & deceptions
in the new hegemony

an  OXFORD FORUM  website

social mobility ‘research’
— on another planet!

The planet Ambrosia, orbiting Betelgeuse, has a simple economy. There are only two jobs: plumber and doctor. Half the working population are plumbers, the other half doctors. And the presence or absence of a single gene determines which job an Ambrosian is suited to.

Not surprisingly, socio-economic position on Ambrosia is highly determined by family background. The vast majority of plumbers are children of plumbers who have inherited their parents’ capabilities. Ditto for doctors.

There is one complication to the genetic picture: one in ten Ambrosians experience a mutation in the womb in which their genes flip from being plumber-type to doctor-type, or vice versa. Fortunately Ambrosian society is enlightened, and long ago eliminated prejudice against these ‘mutants’. Doctor-types always become doctors, even if their parents were plumbers.

What is the level of social mobility on Ambrosia? We can express this as a percentage of plumber-children who become doctors. In this case, the answer is 10 percent. This is also the percentage of doctor-children who become plumbers. (Upward mobility — on Ambrosia as elsewhere — must normally be matched by equivalent downward mobility.)

The child of a doctor has a 90 percent chance of becoming a doctor, while the child of a plumber has only a 10 percent chance. Ambrosian doctors are nine times as likely to come from a doctor background as from a plumber background.

* * * * *

One day Professor Jane Doe, an alien sociologist, visits Ambrosia. She is appalled by what she regards as the poor level of mobility. “10 percent is far too low”, she announces. “Betelgeuse B has mobility levels of 20 to 30 percent, while Betelgeuse C has been steadily rising towards 50 percent. Also, my data suggests that some years ago Ambrosian mobility was higher than 10 percent, and a decrease in mobility is obviously a bad thing: mobility levels should always rise, never fall. With odds stacked against plumber families, Ambrosia is sure to be wasting much of its precious talent.”

“My recommendation is that in future, half of doctors should come from plumber backgrounds, since this reflects the proportions in Ambrosian society. This will of course require that half of those with doctor backgrounds become plumbers.”

* * * * *

Clearly the logic of Professor Doe is somewhat flawed.

Might a visiting sociologist ever have valid grounds for criticising Ambrosia? If mobility was only 5 percent, there would be more of a basis for arguing that doctor-types from a disadvantageous background (i.e. having parents who are plumbers) were being prevented by prejudice or other obstacles from becoming doctors, and that this was both inefficient and unfair.

* * * * *

Some decades after Professor Doe issued her assessment, another sociologist visits Ambrosia. He finds that mobility has risen to 15 percent. When he comes to write his report, is he likely to approve of the increase? If he is being objective, he should note possible problems with a mobility level greater than 10 percent. Such a level is likely to be inefficient; it suggests many Ambrosians are not ending up in the job to which they are suited.

Should our new sociologist urge a return to precisely 10 percent? It depends whether he thinks there are issues of fairness to be considered as well as efficiency.

A sociologist — assuming he or she is relatively rational — might consider deviating from efficiency for the sake of fairness, and might therefore recommend a mobility rate for Ambrosia that is above 10 percent. This would however require the following assumptions to be valid.

1) A significant number of plumber-types actually want to be doctors. There would be little point in imposing a top-down version of ‘fairness’ that depended purely on the preferences of commentators, rather than the preferences of the people they were commenting on.

2) Frustrated plumber-types have not come into existence merely because teachers or politicians have been urging that they ought to want to be doctors, or that they ought to regard it as unfair that they are not.

3) It is explicitly agreed — via whatever collective decision-making process Ambrosians use — that some efficiency should be sacrificed for the sake of increasing the happiness of a few unfortunates. Note that the happiness of others is likely to be decreased, e.g. because some doctor-types are forced to be plumbers, and because this means the average quality of plumbing is likely to decline.

* * * * *

Back to planet Earth. Of course, the biological picture here is not as extreme as on Ambrosia. There is no single gene that determines suitability for different occupations. Job suitability is not only determined by genes but also by environmental factors. People are relatively suited to different occupations rather than being absolutely suited only to one. The possession by a parent of a particular trait does not generally mean the child will have that trait.

Nevertheless, scientific research suggests that there is likely to be a genetic component to aptitude for different tasks, statistically speaking — i.e. some transmission of innate aptitude from parents to offspring on average. We do not know how much, but it is fairly certain to be more than zero. (For some estimates of degree of heritability, see note 4 below.)

For the avoidance of doubt, let me emphasise a point which may seem obvious given what I have just said, but which is evaded or muddled in remarkably many discussions of heritability. Ability being (a) determined 100% by environment or (b) 100% by genes are not the only two possibilities. Critics of the idea of genetic influence seem to like to demonise their ‘opponents’ by identifying them with the 100% genes theory — presumably because this makes it easier for those opponents to be portrayed as ‘uncaring’.

* * * * *

How do Earth’s sociologists approach the topic of mobility? Do they consider the question of heredity before attempting to interpret the raw data? It appears not. Their approach largely mirrors that of our fictional Professor Doe, who believed that more mobility is always better.

A problem is that current data about genetic transmission is too coarse to permit predictions about likely parent-offspring correlation levels. While it is plausible that being the offspring of lawyer parents increases the probability that a person will be suited to being a lawyer (independently of environmental factors), it is not known by how much.

If we knew that it raised the probability of being ‘suited’ from (say) 0.5% to 2%, we might be able to evaluate actual correlations between parent and offspring occupation. If we found that 3% of children of lawyers became lawyers themselves, we might wonder whether the odds were stacked too much in their favour.

Even then, there would be a host of other considerations to be taken into account before we could make a clear judgment. It certainly would not follow automatically that there should be intervention. The distortions generated by initiatives to improve matters might have costs which outweighed any putative benefits.

Using the same hypothetical data, if we found that only 1% of lawyer-children became lawyers (i.e. less than the efficient level of 2%), we might regard this as too low. If the figure subsequently rose to 1.5% we might consider this a positive development, though it would mean a decrease in mobility.

* * * * *

In the absence of such guiding data about the likely effects of genetic transmission on outcome correlations, what can be said about social mobility in the UK, or other countries? Not much, if one is in the role of professional commentator.

As a layman, or man/woman in the street, it is easy enough to come up with opinions. For example:

“People from a middle-class background are over-represented in the professions; this is because of non-genetic advantages. It results in wasted talent.”


“The abolition of grammar schools in the UK has made things harder for clever people from poorer backgrounds.”

Such opinions may be reasonable. They may even be correct. However, without genuinely supportive data, they are just opinions.

As an academic, government spokesperson, or other supposed expert, what can legitimately be said about mobility is actually very little, beyond reporting the raw data. “The correlation between parental occupation and offspring occupation is so-and-so”, or “The correlation has increased over the last ten years”, or “The correlation is lower than the European average” — these are all potentially valid statements.

One could try to link changes in correlation to other social phenomena. Hypothetical example: “Intergenerational correlation has increased since 2004; over the same period, there has also been an increase in the proportion of educationalists who oppose academic selection. The former may be a consequence of the latter.” However, any such link must remain highly tentative. Without the possibility of controlled experiments, social analysts are limited to identifying possible associations. An association by itself can rarely be used to establish a causal connection.

Unfortunately, most academics and other commentators are tempted to introduce value judgments into their discussions of mobility. It appears they cannot resist giving an opinion about whether a given correlation level, or trend in correlation level, is good or bad.

Sometimes the opinion is expressed relatively explicitly. The commentator will make it clear that he or she believes that more mobility is better and that less is worse — without drawing attention to the fact that an alternative belief is possible.

Other times, the message may be implicit rather than stated. However, it is still identifiable by the overall tenor of the article, or by the author’s incidental remarks e.g. about “what the government could be doing”.

What most professional commentators are effectively implying is that there should ideally be no correlation at all with social background. In other words, the commentators believe — or talk as if they believe — that we should proceed on the assumption that there is zero, or negligible, genetic transmission of ability.

* * * * *

Recent publications by the UK government’s Social Mobility Commission provide an illustration of the kind of logic employed by analysts of mobility. In its 2019 Report, the Commission claims that the presence of inequalities has

continued to minimise options for people from poorer backgrounds, further entrenching poor social mobility.

The thesis that social mobility in the UK is “poor” is just asserted, without any attempt to provide a yardstick of what would qualify as good mobility, against which actual figures could be compared. Presumably the Commission is simply adopting the popular belief that mobility is ‘obviously’ well below what it should be, or else it is assuming zero genetic influence. Neither of these assumptions is stated explicitly.

This kind of casual reasoning may be acceptable for a column in the Guardian, but hardly seems appropriate for a government report.

Here is another example of poor logic employed in the 2019 Report, about the alleged financial obstacles to moving within the UK in order to take up a job. Data shows that a relatively high proportion of people from professional backgrounds move to London, compared to the average. This is supposed to prove that those from middle-class backgrounds find it easier to make use of the opportunities created by the recent growth in London-based professional jobs.

However, if:

(A) a disproportionate number of new jobs in a new location are professional,


(B) it is known that in general, a disproportionate number of professional jobs are taken by people from professional backgrounds, whatever the reasons for this (as the Report has already established), then we should expect that:

(C) a higher-than-average proportion of people from a professional background will move to the new location to fill the vacancies.

By merely citing data consistent with phenomenon (C), the Commission has not provided any additional information which might shed light on the relative ease of relocating per se. The data therefore does not, as claimed, demonstrate the contention that those “from privileged backgrounds” are “much more likely, and able, to move and take advantage of London’s lucrative job opportunities.”

The Report paints an overall picture of a web of unfair middle-class advantages, allegedly preventing talented working-class people from rising. The existence of these unfair barriers is supposedly proven by the data presented, though in fact the data does no such thing. The data merely shows that there are non-zero correlations between socio-economic position and socio-economic background.

At times there is a hint of the thesis (Marxist in origin, though by now it has become common among academics) that a deliberate strategy has been adopted by the privileged, aimed at keeping others out. For example, the Report complains that in spite of growth in the number of professional jobs,

those from professional and intermediate backgrounds continue to get most of these top jobs, squeezing out those from the most disadvantaged backgrounds. [my italics]

It is hard to avoid the impression that the use of such language is politically motivated. If the middle class are “squeezing out” the working class, then perhaps we are supposed to regard anti-middle-class policies as a legitimate way to even things up.

* * * * *

How does it come about that sociologists, on whom we ought to be able to rely to provide objectivity and impartiality, in practice generate biased evaluations?

Two possible explanations suggest themselves. One is that a sociologist, faced with difficulties, decides to cut corners: in order to get round a gap in the data he makes sweeping assumptions, but without bothering to state those assumptions. In other words, he is a poor sociologist.

The other possibility is that a sociologist is not being a sociologist at all. He is actually being a political philosopher, but masquerading as a social scientist. That is to say, he is implicitly advocating particular social outcomes as being morally correct, and passing this evaluation off as science — by quoting statistics which are impressive, but beside the point.

* * * * *

Some day in the distant future, the denial of heritability by Western intellectuals — and their demonising of anyone who attempts to break rank — may come to be regarded as one of the more bizarre cultural phenomena of the twenty-first century.

Meanwhile, it can seem at times that many Western intellectuals must be living on another planet.

Take-home message

Numerous articles, reports and blog posts have been written on equality of opportunity in relation to social class. Many of them refer to the results of research to support their arguments. In the vast majority of cases, the research in question has ignored the effects of heritability, without even bothering to disclose that it has done so, thus rendering its conclusions worthless.

This needs to be borne in mind, particularly when research of this kind is used to justify government policy.

Part 2 of this article will continue my examination of social mobility ‘research’. I will look in more detail at the phenomenon of academics sacrificing objectivity for the sake of supposedly beneficial social goals.

© Fabian Tassano

published 22 September 2019


1. For an opinion about what a reader of this article might usefully do, if he or she wants to help talented children from an impoverished background, see my blog post. My recommendation does not involve state intervention.

2. Ambrosia. Sharp readers will have spotted a possible complication with my model, namely mixed marriages. The simplest way to avoid this issue is to assume that Ambrosians reproduce asexually, i.e. each Ambrosian has only one biological parent.

3. Re downward mobility. Advocates for more mobility tend not to mention that upward mobility needs to be matched by downward mobility, other things remaining equal. Evading the minus issue has been facilitated by the post-war growth in the proportion of middle-class jobs, allowing more people to rise than to fall. This growth may be slowing, however, meaning the evasion is becoming less of an option.

4. Degree of heritability. “Heritability” as a percentage refers to how much of the variance in a trait is, on average, due to genetic variation. How any such figure should be interpreted has been a matter of dispute.
The Wikipedia article on Heritability of IQ (retrieved 8 September 2019) states that “the heritability of IQ for adults is between 57% and 73%, with some more recent estimates as high as 80% and 86%”. The same article in January 2018 stated that “the general figure for the heritability of IQ [...] is somewhere between 20% and 50%”.
Based on available data, a current plausible range for the heritability of intellectual traits generally might be 20 to 80 percent. Zero percent seems highly implausible.

5. Re demonising hereditarians. To give just one random example of falsely attributing the 100% genes theory to non-deniers of heredity (encountered via a Google search for “genetic determinism”), the Council for Responsible Genetics — an American think tank — promotes what is no doubt a commonly held image of Charles Murray and Richard J. Herrnstein’s The Bell Curve in claiming that the book

argues that achievement differences are not the result of unequal treatment, access to educational resources, or socioeconomic status, but of genetic differences between individuals or groups.

The Council’s claim is incorrect. Murray and Herrnstein only argue that there is some genetic component to achievement, not that it is the only determining factor. The Council’s claim is not only incorrect but tendentious.

6. One notable exception to the suppression of heritability by social scientists is a 2005 working paper by Christopher Jencks and Laura Tach: ‘Would equal opportunity mean more mobility?’. Interestingly, the paper never seems to have made it into a journal, though it was reprinted in Mobility and Inequality: Frontiers of Research in Sociology and Economics, Stanford University Press, 2006.
The authors themselves note that most researchers “assume that equal opportunity would make [intergenerational correlation] substantially smaller than it is now.”

7. The Social Mobility and Child Poverty Commission, now called the Social Mobility Commission, was set up in 2010 by the Cameron-Clegg coalition government.

8. Quotations from the Social Mobility Commission are taken from State of the Nation 2018-19: Social Mobility in Great Britain, HMSO, pages 2, 3 and 5. The thesis regarding differential obstacles to relocating is discussed on pages 4-7.

9. Re the terms “disadvantaged” and “disadvantageous”, as applied to background. I see a possible point in avoiding the latter term, to avoid stigmatising an individual. On the other hand, it is not clear that the former term is any less stigmatising, and it seems to imply that other people are responsible for doing the disadvantaging.