Let's say you're 18, you're just entering college, and you have decided that your life's goal is to win a Nobel Prize. You don't care which, you just want to taste that sweet Swedish gold. So, what's your best bet? Which is the easiest prize to get?
I'm going to rule out physics, chemistry, and medicine right off the bat. That may be my biophysics science bias showing, but seriously. I don't think you can count on any of those as a good bet. The odds are really astronomical, even if you're fucking brilliant to begin with.
I'm also going to rule out economics, because it's a fake Nobel prize. We're talking the real thing here.
That leaves us with Literature and Peace. I've done my share of writing (including several chapters of a never finished book, and two ten minute plays, one of which was a musical about the life of the Danish astronomer Tycho Brahe, titled Uraniborg), and it's really hard. And I've gotta say, when I read really good writers, I'm usually just left drained, unable to comprehend how they quite do it. Like Michael Chabon, or David Foster Wallace. You can't emulate that, you can't fake it. Writing is hard, certainly hard in a different way than physics, but I think it's even harder to get good at than physics is. I think you pretty much have to be born a writer, there's no two ways about it. You can't just work really hard and get really good at it.
So, that leaves us with Peace. I would say, based on the history of the Nobel peace prize, Peace is definitely the way to go. If Yassir Arafat and Henry Kissinger can win the Nobel peace prize, I think it strongly suggests that there is a serious dearth of people out there trying hard enough, and there must be a few openings. In fact, if you consider the aggregate contribution to overall peace, I think you would probably rank higher than Yassir Arafat if you simply consistently opened doors for old ladies. And let's not forget Mother Teresa, that sainted old lady who won the Nobel peace prize for denying the poor the one thing that would have really actually helped them, which is to say birth control. So, given some of the less than stellar contributions made by these people, I think you've gotta put your money on the peace prize. There seem to be a few different ways to go about it, but I think that if you're genuinely interested in trying to bring peace to the world (or at least genuinely interested in trying to win a Nobel prize), and aren't too worried about material wealth, the field is pretty much wide open. You just pick a cause and run with it until you're out of breath, and hope that people notice.