It is easy to forget that the sociologist Michael Young was making a mild joke when back in 1958 he coined the term “meritocracy” to describe the evolution of Britain and other Western societies. Young did not think the recruitment of the British elite was getting substantially broader or fairer. What had changed was its sense of entitlement: having subjected themselves to competitive examinations and arduous professional training, the children of privilege felt that they had worked for their advantages and owed little to those less fortunate than themselves.

The recent elevation of Young’s son Toby to the peerage is a nice illustration of his argument: although he failed to get the grades he needed to attend Oxford, a phone call from his father to the right person ensured that he got in anyway, preparing him for a career boosting the sort of culture war topics that excite privileged people. In 2007, Young entered Who’s Who, the almanac that styles itself the “dictionary of noteworthy and influential people who impact British life.”

The sociologists Aaron Reeves and Sam Friedman argue that the snobbish longevity of Who’s Who, which has been in print for 125 years now, makes it the perfect source to test claims that Britain’s elite has become more open and more hardworking in recent times. In Born to Rule, they make much of their unique access to its records, which allowed them to compile a complete dataset of anyone who has ever featured in its pages, cross-referenced with information on their wealth and education, the social standing of their parents, and an algorithmic estimate of their ethnicity. Reeves and Friedman also surveyed the cultural tastes and political and social opinions of as many current Who’s Who entries and compared these with the recorded preferences and views of former generations of the great and the good.