Now, let me make one thing perfectly clear. I’ve always said, and I think the American people understand this, that science is a great thing because it’s got a bottom line. It’s got a discipline. You’ve got two fellas, and they don't see eye to eye, they disagree... well, they go right to the tape. They look at the measurements. They go to the world as it is, and the world, frankly, it gives them the judgment. It’s not just some pie-in-the-sky hope for agreement. It is compelled. It’s mandated by the facts.

But then you have metaphysics. And that’s a different kettle of fish entirely. There’s no instrument for it. There’s no experiment you can run in a laboratory to settle the score. It’s asking what reality is like in principle, and let’s be honest, you can have two, three, maybe four different versions of that. All of them consistent, all of them logical, but with no way to arbitrate. No way to call a winner.

And then, of course, you have the personal side of it. The experience. What it’s like to be a human being, looking out from the inside. Now, the academics, they want to put that in a box. They want to model it, they want to measure it. But you can't exhaust the human spirit with a ruler. You can’t capture it in some abstract memo.

When you get to that point, and it’s a difficult point, I’ll be the first to admit it, it’s because you’ve got these different accounts, these different stories, and they’re all coherent. They all fit the facts. And at that stage, there just isn't an observation in the world that’s going to force a resolution. You’re left with the tough choices, the ones where the scientists and the philosophers, well, they just have to step aside.