In the Kantian philosophy of P. F. Strawson (1959, 1966), this framework of necessity is taken in a more common-sense and realist spirit. The world must possess such enduring objects for it to be intelligible for us—indeed, for us to be part of it, for we are essentially stable bodies amongst other stable bodies. The important point for both Strawson and Kant is that there must be substances for there to be a coherent empirical, spatio-temporal world. Substance has become a formal concept of cen