This distinct twist of the population story, which accompanies research showing a shift from nearly 90 percent of the Jewish population engaging in agriculture to nearly 90 percent engaging in professional trades over that same several hundred years, addresses a key problem of previous theories of Jewish literacy: determining what happened to those who wouldn't be scholars.
Botticini and Eckstein bring other evidence of Jewish tradition generating success in trade. An extrajudicial system of rabbinical courts for settling disputes allowed for the development of the kind of trust required for commercial enterprises to grow. A universal language of Hebrew eased international negotiations. And in a devastating critique of the theory that persecution actually pushed this economic shift along, the economists examine the societies in which Jews originally developed this bias toward trades and find Jews faced no particular discrimination that would have made them less successful in agriculture. In fact, they show, Jews were often discriminated against precisely because of their emphasis on trade, such as in their expulsion from England in 1290, which only came after they were repeatedly told to give up the profession of money lending (eventually echoed in Ulysses S. Grant's order to expel the Jews from the territory under his command during the Civil War).
And so the Jewish people have grown into a people of two intertwined legacies: a culture in which the Jewishly literate continue to pass the torch and one in which an emphasis on trades was necessary to continue to do so for all but the most fervently devoted. When a given family stopped being devoted or wealthy enough, it simply faded away.
The astonishing theory presented here has great implications for both the Jewish community and the broader world today. For an American Jewish community in which more than 75 percent of day school students are now Orthodox and the top concern for most Orthodox families in repeated surveys is finding a way to pay for ever-increasing tuition costs, the price of admission to the highly affiliated Jewish community is not just a large amount of ritual observance but also a basic need to join the 1 percent—or nearly so. Frequently, one can hear Orthodox Jews joke that $250,000 a year is "minimum wage" for the community; certainly, this overstates things but only by so much. In the New York area, elementary school often carries a price tag of $15,000-$25,000 in post-tax dollars per year; at the high-school level, some tuition rates are well into the $30,000 range. Outside of the New York area, tuition is generally lower, but so is the average income. And as Botticini and Eckstein predicted for their medieval models, modern American Jews who are fiercely devoted but without high incomes will endure significant financial sacrifice to maintain their Jewish lifestyles: The ultra-Orthodox enclave of Kiryas Joel, N.Y., is the poorest city in the country, and ultra-Orthodox communities broadly are frequently both poor and heavy recipients of government assistance.
And for most of the 80 to 90 percent of families representing the non-Orthodox portion of the Jewish community in America, the cost of Jewish education has simply meant great numbers growing up without the ability to read Hebrew or engage with the Bible and other Jewish texts.
Here we see precisely the same dichotomy that Eckstein and Botticini saw in the early years of post-Temple rabbinic Judaism: The especially devoted and wealthy provide their children with a Jewish education, but many others see too high a price in either or both of time and money and so choose a different path.
And yet, so many of today's unlettered Jews have been able to retain at least some sense of Jewish identity, where their predecessors 1,500 years ago could not. A majority of American Jews today are unaffiliated with the synagogues the Pharisaic rabbis emphasized, and yet 79 percent report feeling "very positive" about being Jewish. In part, Botticini and Eckstein would likely argue, that's because of America's unique tolerance of Jews, which removes the economic disincentive of maintaining an identity as a Jewish minority even when one doesn't have a very strong connection to Judaism.
At the same time, today's unaffiliated Jews no longer face an economic disadvantage relative to those attending Jewish schools: The aim for universal literacy in America broadly, and increasingly in all corners of the world, has led to the same kinds of professional opportunities for many people in the way that Jews used to have largely to themselves. Or, as Eckstein put it in an interview with me, "Almost everybody has become Jewish, because almost everybody is literate."
You can view highlights of the Eckstein interview in the video below: