Abstract
Substance ontologists claim that substances are ontologically primary because the category of substance enjoys unique explanatory potential. Unless it can be shown that "only" substances fulfill the central explanatory tasks in ontology, this inference from explanatory success to ontological primacy amounts to a fallacy akin to the error Whitehead called 'the fallacy of misplaced concreteness'. I investigate recent prototypical arguments for substance metaphysics and try to show that some explanatory functions of substance can also be fulfilled by other ontological categories. In particular, I argue against M. Ayers that there is no reason to think that all and only substances are discrete individuals, natural wholes, and logical units. I conclude that the category of substance does not provide us with a uniquely powerful explanans for the notion of logical and physical unity.