It has been noted in the HBDsphere that the Christian
Arabs sorry N.N. Taleb, I meant Phoenicians, Copts, Maronites, Alawites, etc., have been rather successful relative to their Muslim neighbors.
This is true for economic achievement (e.g. Carlos Slim, Steve Jobs) and for intellectual achievement (e.g. Albert Hourani, Skin In The Game man).
However, in a recent paper by Mohamed Saleh, it is suggested that poorer Egyptians converted to Islam, to avoid the poll tax on Christians, while the richer ones stayed put as Copts.
Self-selection of converts is an under-studied explanation of inter-religion socioeconomic status (SES) differences. Inspired by this conjecture, I trace the Coptic-Muslim SES gap in Egypt to self-selection-on-SES during Egypt’s conversion from Coptic Christianity to Islam. Selection was driven by a poll tax on non-Muslims, imposed from 641 until 1856, which induced poorer Copts to convert to Islam leading Copts to shrink into a better-off minority. Using novel data sources, I document that high-tax districts in 641–1100 had in 1848–1868 relatively fewer Copts, but greater SES differentials. Group restrictions on apprenticeships and schooling led the initial selection to perpetuate.
The paper convincingly attributes the declining share of the Coptic population to the poll tax on non-Muslims driving conversions, especially amongst the poor (immigration and fertility differentials are ruled out). Indeed, a existence of a socio-economic status gap between Copts and the Muslims is established to more than a millennium ago. Moreover, the Copts’ rate of decline as a share of the population correlated with the size of the poll tax during various periods.
It should be noted that the author rejects genetic differences as a means of explaining the persistence of ability differentials. This is primarily justified by making arguing that SES in medieval Egypt was weakly correlated with ability, and by noting that the possibility of rich Copts marrying poor Copts would result in “regress to the population mean.” I am not sure I buy this. Even if the selection effects were small, they were active in play for more a millennium.