Why are so many people even talking about IQ
Btw I found out recently that JP's thing about Jews and high IQ is wrong. Ashkenazi Jews had an average iq of about 98 before the first world war, so it isn't an adequate explanation for their prevalence in high status occupations. This factoid brought to you by Cindi's dad, Thomas Sowell.
Not a historian on Jewish history, and have no idea how much this satisfies all the points, but I do know from reading various historical readings and from studying economic history, that Jews, as was often the case throughout history, were ostracized, marginalized, persecuted, and banned from many occupations(like farming and numerous trades) and were denied many core rights like those of certain forms of land and property ownership. However, many of the organized religions and their respective societies banned or heavily restricted interest charges, and while it was banned in Judaism between fellow Jews, it was less so for non-Jews and Jews. And the often Christian controlled societies looked past Jew to Christian loans, even at excessive usury rates. So readily available access to credit being a sort of necessity many societies felt needed(and it could indirectly help enrich the permanent upper class, especially if you force them to operate with some predatory bullshit, which is always a bonus for the rich), certain societies, like within parts of Europe, let Jews take on the socially stigmatized(but necessary) roles of banking, tax collecting, and rent collecting. Thats not to say they were the only ones in those occupations, plenty of Christians engaged in that during Medieval periods, but it does seem that by necessity and survival, a larger percentage of the Jewish population relative to others found there way to those sort of occupations.
Throw back into the pot the often laws against property rights for Jews, which naturally meant they held greater levels of liquid assets. Which is a benefit as a lender. And one thing you can get a nice return on as a lender is the merchant trade. And it just so happens Jews were often geographically dispersed(due to lovely things like persecution and massacres), but lived in close knit, often isolated communities due to their overhanging present and past circumstances. Lots of liquid capital in a growingly profitable industry, large geographic dispersion, but a close knit network to pull from, thats a pretty good formula for the merchant trade.
They began in trades that were actually considered low status, looked down on, it was only after a long period of time that the stigma of many of these occupations lifted that they were considered of higher status in society.
As a side note, you can sort of see where many of the later stereotypes - ignorant of this context - come from in Europe and elsewhere.