That's a good observation. Much of Greenspun's theory is based on male irrationality (men are more likely to pursue science Ph.D's because they are less likely to make sensible decisions than women). However, the legions of women in lit PhD programs proves that they, too, can be incredibly irrational by this standard.
A few possible differences... Greenspun does include "quantitative ability" in his agument that "Adjusted for IQ, quantitative skills, and working hours, jobs in science are the lowest paid in the United States." This wouldn't include lit students. However, women who purse lit Ph.D's could still do law school, and perhaps B-school.
Another factor is that nobody is trying to trick women into lit PhD's by claiming that there's a shortage, whereas many people in high positions in the US government and corporations do promote the notion that there's a critical shortage of Americans pursuing PhDs in math, physical science, and engineering... though still, this doesn't really address the "irrationality" of lit PhDs - it just means that there isn't an industry of pushing people into degrees that don't pay in the humanities.
Anyway, this is a good observation, definitely a potential weakness in Greenspun's argument.
It's possible that the women in English lit are taking a comparatively smaller cut in salary, but there aren't that many English lit jobs; far fewer than in the sciences. The competition for jobs is much greater, making the probability of finding a job even worse than in science.
While the "men prefer prestige to money" theory has some merit, the "women prefer security to money" is better established.
Men who pursue science Ph.Ds can also still do law school, or B-school. And a physics Ph.D who also has a J.D in intellectual property or an MBA in finance is incredibly valuable.
I agree that a physics PhD + JD or MBA degree is very valuable, probably more valuable than the JD or MBA alone, but does it overcome the opportunity cost? We're talking 7+ years of lost income, plus the possibility of extra student debt.
In pure monetary terms, probably not, unless you start your own hedge fund. But it'll let you work in areas that just a JD or MBA would not, and for a lot of people that's valuable. And you're not nearly as financially behind as if you'd gotten the straight Ph.D and played the tenure/academia game.
A few possible differences... Greenspun does include "quantitative ability" in his agument that "Adjusted for IQ, quantitative skills, and working hours, jobs in science are the lowest paid in the United States." This wouldn't include lit students. However, women who purse lit Ph.D's could still do law school, and perhaps B-school.
Another factor is that nobody is trying to trick women into lit PhD's by claiming that there's a shortage, whereas many people in high positions in the US government and corporations do promote the notion that there's a critical shortage of Americans pursuing PhDs in math, physical science, and engineering... though still, this doesn't really address the "irrationality" of lit PhDs - it just means that there isn't an industry of pushing people into degrees that don't pay in the humanities.
Anyway, this is a good observation, definitely a potential weakness in Greenspun's argument.