U. Cal., Davis economist Gregory Clark:
When you look across centuries, and at social status broadly measured — not just income and wealth, but also occupation, education and longevity — social mobility is much slower than many of us believe, or want to believe. This is true in Sweden, a social welfare state; England, where industrial capitalism was born; the United States, one of the most heterogeneous societies in history; and India, a fairly new democracy hobbled by the legacy of caste. Capitalism has not led to pervasive, rapid mobility. Nor have democratization, mass public education, the decline of nepotism, redistributive taxation, the emancipation of women, or even, as in China, socialist revolution.
o a striking extent, your overall life chances can be predicted not just from your parents’ status but also from your great-great-great-grandparents’. The recent study suggests that 10 percent of variation in income can be predicted based on your parents’ earnings. In contrast, my colleagues and I estimate that 50 to 60 percent of variation in overall status is determined by your lineage. The fortunes of high-status families inexorably fall, and those of low-status families rise, toward the average — what social scientists call “regression to the mean” — but the process can take 10 to 15 generations (300 to 450 years), much longer than most social scientists have estimated in the past.