Class, Culture, or Genes?

I found this article on long term social mobility rather interesting. It's a semi-review of The Son Also Rises: Surnames and the History of Social Mobility by economist Gregory Clark, which seeks to look at the extent to which wealth or poverty persists through generations.

He set out thinking the social-science consensus was correct, intending only to extend those findings further into the past. But the evidence changed his mind: social scientists have been measuring mobility the wrong way, and in fact the popular intuition is on target.

The key to understanding Clark’s thesis is his division of the factors that make for success in worldly affairs into an inherited component and a random component. (“Inherited” here need not mean “genetic”: one could inherit, for instance, one’s family’s reputation.) Most previous studies have focused on movements in social class from one generation to the next. But as Clark explains using his two-factor model, such a limited time frame means that the random component of social achievement is going to have an undue influence. This is not an esoteric notion: think, for instance, of a member of a high-achievement family who suffers a terrible car accident as a youth, leaving him with severe brain damage. It is quite likely that whether measured by income, profession, or educational level, that member will do significantly worse than the family average.

But this accident will not change the family’s basic “social competency” (Clark’s term). If the injured son has children, they will not inherit his brain damage. Their level of achievement will tend to return toward the family baseline. So, Clark suggests, if we really want to measure social mobility, we should look at the social status of families over many generations.

The way he and his team of researchers did so is ingenious: they found relatively rare surnames primarily associated with high social standing, such as the names taken by the nobility in Sweden, or low social standing, such as names characteristic of the Travellers in England, and tracked their appearance in historical records showing elite status, such as admissions to top universities—for Oxford and Cambridge, we have data dating back 800 years—large estates bequeathed in probate, or presence in high-status professions such as law and medicine.

The results confirm that the popular intuition has been correct all along:

The intergenerational correlation in all the societies for which we construct surname estimates—medieval England, modern England, the United States, India, Japan, Korea, China, Taiwan, Chile, and even egalitarian Sweden—is … much higher than conventionally estimated. Social status is inherited as strongly as any biological trait, such as height.

What’s more, it matters little what social policies are put in place: Clark and his team find that social mobility remains nearly constant over time despite the arrival of free public education, the reduction of nepotism in government, modern economic growth, the expansion of the franchise, and redistributive taxation.

Clark introduces us to the reality of this persistence of status with a few notable examples. For instance, the family of famed diarist Samuel Pepys has had high social status from 1500 until today, while that of Sir Timothy Berners-Lee, creator of the World Wide Web, apparently has been upper crust since the Domesday Book of 1086. And in noting the many prominent members of the Darwin family, he remarks, “It is also interesting that Darwin’s fourth-generation descendants include Adrian Maynard Keynes and William Huxley Darwin.” The elite tend to marry the elite.

But if such isolated examples were the crux of Clark’s case, it would be a rather flimsy one: even if the standard social science take on mobility were correct, we would expect to find notable exceptions to the general rule. His main backing for his thesis is a number of studies conducted across many countries and many centuries. Nevertheless the anecdotes are an important aspect of this work: they are a component of how Clark continually turns what could have been an extremely dry executive summary of a number of demographic surveys into a consistently engaging book.

The method and the findings here both strike me as fascinating.

One of the points that strikes me as particularly interesting is the point that if how well you do is a combination of family factors and personal factors, that looking at the difference between fathers and sons would tend to magnify the important of personal factors, while looking over more generations would give more of a sense of family factors. This should ring true to any lover of Victorian and earlier novels: distressed nobility may be distressed, but they're still nobility, and thus they have more ability to get themselves back up into the range of other nobles than do non-gentlefolk who may have similar incomes.

The article, however, surprises me a bit in that it seems to assume (whether this mirrors the book or now I don't know) that if certain families seem to continue to achieve highly through many generations, that this must be entirely the result of unshakable class privilege. I would imagine that class is a factor, but it seems likely that family culture and genetics come into it as well.

Culture and genetics would help to explain the phenomenon of immigrants from an educated/genteel background coming to a new country with nothing, yet somehow ending up within a generation or two back in the upper middle class. Obviously, given the shift of cultural context, it's unlikely to be the result of class power or influence and more likely to be the result of some combination of family culture and natural abilities passed down through genetics.