 Individuals have natures, and in virtue of their natures they belong to determinate natural kinds. But an individual’s nature is not something really shared with or common to other individuals; Abelard’s refutation of realism has shown that this is impossible. Instead, Abelard takes a natural kind to be a well-defined collection of things that have the same features, broadly speaking, that make them what they are. Why a given thing has some features rather than others is explained by how it got that way—the natural processes that created it result in its having the features it does, namely being the kind of thing it is; similar processes lead to similar results. On this reading, it is clear that natural kinds have no special status; they are no more than discrete integral wholes whose principle of membership is similarity, merely reflecting the fact that the world is divided into discrete similarity-classes of objects. Furthermore, such real relations of similarity are nothing themselves above and beyond the things that are similar. The division into natural kinds is, presumably, a ‘shallow fact’ about the world: matters could have been otherwise had God ordained them differently; fire might be cold, heavy bodies fall upwards, frogs reason. If these causal powers were different, then natural kinds might be different as well, or might not have been as sharply differentiated as they are now. Given how matters stand, natural kinds carve the world at its joints, but they are the joints chosen by God.