 So one of the kind of narratives that you lay out in the book is the sort of, you know, Paul Ryan school of kind of pure spending reduction, or not pure, but heavily spending reduction based approach to running in the deficit, you know, versus, you know, I mean the Obama approach generally I guess. And it's interesting because if you see this debate between the administration and Paul Ryan and Democrats and Paul Ryan play out, you would get the impression that they regard this guy as kind of a budgetary anti-Christ who's just bent on, you know, on destroying their most cherished values. And but if you actually talk to sort of administration budget wonks, and I'm sure you guys have had similar conversations, you sort of hear things like, well, you know, not so crazy, I mean, if you know, if we could imagine doing a sort of Medicare voucher type thing, we would fund it more generously than he does, we would make sure it kept up with, you know, medical inflation over time, but, but it's not so crazy, you know. A, I'm wondering, do you guys sort of hear similar things, and B, do you think that that could be kind of an end game for what we do to rein in Medicare over the long term? Well, one, yes, they made him the anti-Christ because it's a famous game in Washington, you need an enemy, and Paul Ryan was providing a pretty juicy target given the size of some of his spending cuts. Second, I think there's always grudging respect in this debate between the both sides when they think the other guy knows what he's talking about, which, as you know, is not a threshold that most members of Congress meet on this subject. So you always have to admire the guy who plays his cards well and knows what he's talking about and seems to have some intellectual discipline. I think the healthcare thing is a riot in one respect. So basically, if you listen carefully to the debate and then extrapolate from it the way journalists do, President Obama thinks we should have exchanges for everybody under 65, but not for people over 65, and the Republicans think the opposite. So I can imagine a day when we get to some defined contribution healthcare in Medicare, after all, there is, you know, Ron Wyden and Alice Rivlin, some people on the Democratic side have proposed those things. I doubt it's going to happen soon, but I wouldn't be surprised if you were talking about a decade or two decade long horizon that we go there. You point out exactly the problem is that it's a little hard to know how to price the thing so that you keep the pressure on the system to not let costs go out of control. You get the benefits of competition, like we got in the prescription drug thing, but you don't end up making it impossible for people to get the healthcare that they need. And I think that even Larry Summers and Peter Orszag haven't figured out quite how to do that, although they're working on it, and by Friday they'll have an answer. Mark? Yeah, I mean, well, Congressman Ryan is kind of both a wonk and an ideologue, and I think folks from all stripes respect his wonkdom and respect that. I mean, if you spend some time in the room with him, he really does nobody's talking about it, and he knows budget numbers better than people that work at CBO sometimes. But he also has a very ideological view of what the world should look like, which of course, as a politician on the other side, you're going to attack. That's natural. In terms of whether his plan of premium support of some type can be the end game, I kind of, I agree with David. This is controversial, but healthcare is on such an unsustainable course that there will probably have to be some type of rationing at some point. And so then you have to ask yourself the question, is the government going to do the rationing, or is the private sector? Because either way it's going to be rationing. Then it's a political question, which do you think the American public will be more accepting of? I don't know the answer, but I wouldn't rule out something like this as an option.