"Contemporary discussion of inequality in America often conflates two related but distinct issues: * Equality of income and wealth. The distribution of income and wealth among adults in today's America--framed by the Occupy movement as the 1 percent versus the 99 percent--has generated much partisan debate during the past several years. Historically, however, most Americans have not been greatly worried about that sort of inequality: we tend not to begrudge others their success or care how high the socioeconomic ladder is, assuming that everyone has an equal chance to climb it, given equal merit and energy. * Equality of opportunity and social mobility. The prospects for the next generation--that is, whether young people from different backgrounds are, in fact, getting onto the ladder at about the same place and, given equal merit and energy, are equally likely to scale it--pose an altogether more momentous problem in our national culture. Beginning with the "all men are created equal" premise of our national independence, Americans of all parties have historically been very concerned about this issue."