Credential inflation refers to an increase in the education credentials required for a job—for example, a job that used to be done by high school graduates but now requires new hires to have a college degree. Credential inflation has been going on for decades. One of the earliest mentions of it is in professor Randall Collins’ book The Credential Society, published in 1979 and republished last year; two recent studies give a sense of how widespread it has become. The first, a study by Burning Glass, looked at the education level of current workers compared to the education level listed...