Mainstream historical models have long assured us that as ancient cities grew wealthy and sophisticated, opportunistic kings and greedy priests inevitably widened the gap between the rich and poor. A recent University of York analysis of legacy data from Mohenjo-daro shatters this comforting narrative by demonstrating that household sizes grew remarkably more equal as the urban center matured. Apparently, someone forgot to brief the 4,000-year-old metropolis on how proper class stratification is supposed to work.