Who's On Your Shoulder?

Ezra Klein engages in some interesting introspection:

Nowadays, I know that folks from that end will be looking to cut apart my ideas, I have to protect my points against their insights which, in turn, means I absorb their insights. I've a little libertarian on my shoulder (as well as a little feminist, mid-sized populist, rather large labor leader, and a variety of other shoulder-sized ideologues) and my writing is stronger for it.

Personally, the figure most likely to be on my shoulder is my Econ 1 teacher, Bill Dickens. He's my archetype of a smart, decent, creative, open-minded economist who doesn't share my libertarian sympathies. If I can write something that makes him think a second time, I'm satisfied.

How about you? Who's on your shoulder?