51. You are surrounded by undergraduates.

Most everyone who works in education experiences the strange phenomenon of growing older while students stay the same age. Graduate students experience an even stranger phenomenon. While still students themselves, they age in the presence of fellow students who remain 18-22 years old, year after year after year. As a graduate student, you encounter undergraduates every day on campus. It is more than likely that you have to work with them. And because you can’t afford to live anywhere else, you probably go home to a neighborhood (or even an apartment building) that is full of them. They surround you constantly. In fact, in ways that seem more distressing over time, your life is very much like theirs.

It is not much fun to live in a sea of undergraduates unless you are an undergraduate yourself. Their unavoidable presence and carefree ways are a constant reminder of your delayed adulthood (see Reason 12), even as their feeling of relief and accomplishment at the end of each term is a jarring reminder that your own work does not end with finals week (see Reason 47). You may not be much older than they are, but they can make you feel much older than they are. And then one day you discover that you are much older than they are. Perhaps most bothersome of all is their collective sense of possibility; they know (or at least live in the belief) that a world of opportunities awaits them, while you see more clearly every year that your prospects are becoming fewer and fewer (see Reason 29).