The notion of a generational clash has been around for generations. The old grow older, the young grow up, the latter challenge the former, the former lament the latter, and society moves forwards, improving every time. That was the idea, anyway. As Karl Mannheim wrote in a seminal essay of 1929, “The Problem of Generations”, for centuries “the succession of generations was considered as something which articulated, rather than broke, the unilinear continuity of time”. After two world wars briefly suspended this meliorist myth, between the late 1940s and the early 70s babies boomed and economies boomed with them. The generations clashed – “Don't trust anyone over the age of 30”, ran a popular slogan of the 1960s – as societies witnessed periods of unprecedented prosperity. Progress, it seemed, was forever – again. And then the millennials came along – the resented, resentful cohort of the 1980s and 90s.