By age 25, it’s time to grow up.

19. Take care of yourself. If you are sick, visit a doctor. If you are sad, visit a shrink or talk to a friend. If you are unhappy in love, break up. If you are fed up with how you look, buy a new shirt or stop eating cheese. If you have a problem, try to fix it. Many problems are knotty and need a lot of talking through, or time to resolve, but after a few months of all complaining and no fixing, those around you will begin to wonder if you don’t enjoy the problems for the attention they bring you. Venting is fine; inertia coupled with pouting is not. Bored? Read a magazine. Mad at someone? Say so — to them. Change is hard; that’s too bad. Effort counts. Make one. Your mommy’s shift is over.

The whole list is well worth reading; it crystallizes a lot of what I sort of generally sensed about the difference between me and the undergrads, when I arrived on campus to start work on the ol’ Ph.D. Via kottke.