One rough way to test this hypothesis would be to look at whether the decline in history majors across the United States is also seen at elite institutions.

If 1) degrees are primarily a social signal, 2) the value of that signal is declining as a larger percentage of the population goes to college, and 3) employers have thus shifted to selecting on majors to separate wheat from chaff, it follows that students attending selective Ivy League institutions will feel less pressure to choose majors that signal their intelligence and discipline. University attendance may no longer be a mark of exclusivity; Harvard attendance certainly still is.

Americans once believed, *earnestly believed*, that by studying the words of Milton and Dante, or by examining the history of republican Rome or 16th century England, one could learn important, even eternal, truths about human nature and human polities. Art, literature, and history were a privileged source of insight into human affairs. In consequence, those well versed in history and the other humanistic disciplines had immense authority in the public eye. The man of vaulting ambition studied the humanities.

One of the most important intellectual developments of the 21st century—something that I hope to highlight in my own book on this era—is the growing prestige and public authority of two modes of thought. I struggle to label the first group with one word—I waffle between "the modelers," "the data heads," and "the social scientists." This group is comprised of psychologists, cognitive scientists, computer scientists, data scientists, statisticians, economists, quantitative sociologists, geographers, anybody who uses the word "computational" in front of their job description, and anybody whose main method of public engagement is a dynamic data visualization. Data is the watchword of these folks, empiricism their vocation, science their title.

Rising to meet the modelers are the intersectionalists. The two approaches have more in common than is initially apparent. Both modes idealize the counterintuitive insight. Practitioners of each believe that the masses are content to live in a world of surface realities; both groups secure their public standing by tearing away the truisms of everyday life to expose the true workings of the world.

The basic idea is that you have a series of candidates you are interviewing for the role of secretary (this conception of the problem spread in the 1950s). You view each candidate one by one and must decide on the spot if you will stop your search there and hire the candidate in front of you. If you move to the next candidate, the past candidate is gone forever.

To maximise your probability of finding the best secretary, you should view 37% of the candidates without making any choice, and then accept the next candidate who is better than all you have seen to date. This rule gives (coincidentally) a 37% chance of ending up with the best mate.

What if, like most people, you have a degree of risk aversion - particularly if you are applying the rule to serious questions such as mate choice. Suppose there are 100 candidates and you want someone out of the top 10%. In that case you only want to look at the first 14% of candidates and choose the next candidate who is better than all previous candidates. That gives you an 83% chance of a top 10% candidate. If you will settle for the top 25%, you only need look at the first 7% for a 92% chance of getting someone in the top quartile.

In larger populations, you need to look at even less. With 1000 people, you need only look at only 3% of the candidates to maximise chance of top 10% at 97% probability. For a top 25% mate, you should only check out 1 to 2%.