In college, I took a class about the relationship between science and literature. One thing the professor said really struck me. We were talking about the earth-centric view of the earth and how Keppler changed that. He said that a lot of times, we say something like "they used to think, but now we know..." , but that we need to be careful about it. The paradigms people had in the past worked well and explained things. He talked about how the earth-centric view (the earth is the center of the universe) actually worked pretty well. It only need to be updated a few times in several hundred years.
What got me thinking about this was a blog entry I had read about simple answers. The author mentioned the bible story of how God created the earth in seven days. That that explanation isn't wrong, just simple. The people at the time didn't need more. I think though sometimes when we make explanations like this, we have this implicit assumption that "of course, today we'd completely understand it, unlike those poor ignorant people in the past." The thing is, God hasn't added much else to how he created the earth which means either it isn't really important to our salvation or we aren't as advanced as we think. What a nice kick in the pants :)