David Lewis and the Kangaroo: Graphing philosophical progress

Data-driven historiography of philosophy looks to objective modeling tools for illumination of the propagation of influence. While the system of David Lewis, the most influential philosopher of our time, raises historiographic puzzles to stymie conventional analytic methods, it proves amenable to data-driven analysis. A striking result is that Lewis only becomes the metaphysician of current legend following the midpoint of his career: his initial project is to frame a descriptive science of mind and meaning; the transition to metaphysics is a rhetorically breathtaking escape from this program's (inevitable) collapse. Understanding this process both aids a more focused debate whether it counts as progress, and also presents novel affordances for partisans on both sides to learn from Lewis's right and wrong steps.