 Admittedly, points in space and time have locations. But concrete entities are only accidentally where and when they are. All concrete entities have intrinsic properties (which make their boundaries natural rather than conventional, say Efird and Stoneham (2005, 314)). Their natures are not exhausted by their relationships with other things. Max Black imagines twin iron spheres in an otherwise empty universe. The spheres are distinct yet have the same relationships and the same intrinsic properties.