The Two-Year PhD

A reader emails me:

Dear Professor Mankiw,

I'm a student in an econ PhD program. I've read "JD vs PhD: My Story" on your blog. Correct me if I'm mistaken, but you finished your PhD in two years. (Lucky you, only 2 years of torture!!) How did you manage to finish the coursework and the research in just two years?

[name withheld]

Yes, I managed to earn a PhD in two years of residence at MIT. Here is how:

1. During my last year as an undergrad at Princeton, I took the standard graduate sequence in micro and macro. When I arrived at MIT, I was effectively a second-year PhD student.
2. After my first year at MIT, I went for a year to Harvard Law School, where I was more concerned about writing economics articles than being a diligent law student.
3. After the year in law school, I went to the CEA as a staff economist, where I worked for senior staff economist Larry Summers, who served also as an academic adviser. Because I worked on research between CEA tasks, when I returned to MIT for my second year, I had much of my dissertation already completed.

In short, my PhD really took five years of elapsed time, but while doing it, I managed to squeeze in a few other things: finishing my undergraduate degree, being a first-year law student, and working at the CEA.