  Until recently, very little has been written directly on Kant's Phoronomy. (By contrast, Kant's philosophy of mathematics has long received considerable attention.) Palter (1972) first broached the Phoronomy from the modern standpoint of coordinate transformations between frames. Pollok (2001) is a historically rich commentary. Friedman (2013) untangles the complex strands of thought in Kant's chapter. His leading idea is that Kant's categories of quantity (of the First Critique) guarantee that motion is a magnitude, hence mathematics is applicable to the motions of bodies--as kinematics.