A human being should be able to...

A human being should be able to change a diaper, plan an invasion, butcher a hog, conn a ship, design a building, write a sonnet, balance accounts, build a wall, set a bone, comfort the dying, take orders, give orders, cooperate, act alone, solve equations, analyze a new problem, pitch manure, program a computer, cook a tasty meal, fight efficiently, die gallantly. Specialization is for insects.

– Robert Anson Heinlein via Rules for My Unborn Son (via NO BLASTERS!)

I appreciate this idea, and am trying to better follow it, even though the process of getting a PhD is specialization in one particular area of study.