Abstract

An influential line of thought in metaphysics holds that where common sense discerns a tree or a dog or a baseball there may be just many microparticles. Provided the microparticles are arranged in the right way -- are “treewise” or “dogwise” or “baseballwise” arranged -- our sensory experiences will be just the same as if a tree or dog or baseball were really there. Therefore whether there really are suchfamiliar objects in the world can be decided only by determining what more is needed for microparticles dogwise arranged actually to compose a dog. This paper argues that this line of thought sets up the wrong agenda. Composition is trivial; dogwise (etc.) arrangement is tricky. Dogwise arrangement will obtain in the wrong regions unless we stipulate that there are dogs, and that dogwise arrangementobtains only within their borders. The bearers of dogwise arrangement, moreover, will have to be dogs themselves, not their microparticles. Thus allowing that dogwise arrangement obtains at all is allowing that there are dogs