Suppose your law firm wants a summer associate. A law student with a doctorate in philosophy from Stanford applies. What do you infer? The applicant is probably brilliant, diligent, and willing to tolerate serious boredom. If you’re looking for that kind of worker—and what employer isn’t? – you’ll make an offer, knowing full well that nothing the philosopher learned at Stanford will be relevant to this job.
The labor market doesn’t pay you for the useless subjects you master; it pays you for the preexisting traits you signal by mastering them. This is not a fringe idea. Michael Spence, Kenneth Arrow, and Joseph Stiglitz – all Nobel laureates in economics – made seminal contributions to the theory of educational signaling. Every college student who does the least work required to get good grades silently endorses the theory. But signaling plays almost no role in public discourse or policy making. As a society, we continue to push ever larger numbers of students into ever higher levels of education. The main effect is not better jobs or greater skill levels, but a credentialist arms race.
Lest I be misinterpreted, I emphatically affirm that education confers some marketable skills, namely literacy and numeracy. Nonetheless, I believe that signaling accounts for at least half of college’s financial reward, and probably more.