“Transportation is such an easy progress to measure...We have a bias toward the easy number, but it doesn't always mean what we want it to mean. And if we're going to think about it clearly---and write the kind of science fiction that shows real progress on all fronts, not just one---we need to think of different ways to measure it...If we can measure not just miles but good miles---not just good miles but the people who travel them with us, the places we have preserved along each of those miles---then we'll be another step closer to understanding what progress can look like in the futures we imagine.”