The story of how a map of the world helped Copernicus to rethink the universe is rarely told. But the connection tells us something important about how great ideas are born. To understand it, we need to recall that medieval scholars didn’t consider geography and astronomy to be distinct disciplines. Instead, they considered them parts of a single field called cosmography – the study of the known world and its place in the cosmos. One of the field’s guiding principles went something like this: Looking down, we see up; looking up, we see down. By carefully studying the earth, cosmographers believed they could learn about the heavens, and by carefully studying the heavens they believed they could learn about the earth. Copernicus himself was a cosmographer, and shared this view. We remember Copernicus as one of the first great thinkers of the modern scientific era, but he inhabited a profoundly medieval thought-world – a world in which astrology and alchemy commanded as much attention as geography and astronomy. For all its obvious and sometimes laughable shortcomings, the medieval approach to learning was far more integrated than our own, and it allowed Copernicus to think on a truly grand scale. From a cosmic vantage point he looked down, at a map, and what he saw made the skies open up.
more from Toby Lester at the Boston Globe here.