“It’s not unreasonable to hope that such a world would be peaceful, just, tolerant and prosperous… Could this really happen? Could we use modern quantitative ideas to make the Dark Ages financially secure without technological progress or force of arms or great political ideas? I think it’s possible. I don’t underestimate the practical problems. I would give long odds against any individual succeeding. But I think the ideas have real power, and could be explained to people in the sixth century.”