Folk Mereology is Teleological

When does mereological composition occur? For instance, if a paper plate is positioned on a table between a plastic knife and a metal fork, does this scattered plurality of diverse objects make up a single composite object (a “table setting”) or not? Or if two people shake hands, does this connected plurality of similar objects make up a single composite object (shaped like a sculpture of two people shaking hands) or not? In general, when does a collection of things form a whole? Many metaphysicians have wanted a view of composition that respects folk intuitions and have charged leading views with failing on this score. For instance, Hirsch declares that “the linguistic evidence indicates that fl uent speakers of English do not speak the mereologist’s language” ( 2002 : 60). And Markosian sets out from the claim that “no one has yet defended a view . . . consistent with standard, prephilosophical intuitions about the universe’s composite objects” ( 1998 : 211). Yet there is widespread disagreement among metaphysicians as to what the folk intuit about mereological composition and why they do so, and no empirical discipline to the debate. We see this situation as an opportunity to put the tools of experimental philosophy to constructive use. Accordingly we aim to discover when the folk tend to think that composition occurs and why they do so. So our question is: when do the folk think that mereological composition occurs ? Th at is, what is folk mereology , against which metaphysical accounts of real mereology might be measured? Our question— beyond whatever intrinsic interest it might possess— should be of interest to anyone interested in the psychological question of how humans conceptualize the world, and in the connected project of descriptive metaphysics. Whether our question is also relevant to prescriptive metaphysics is controversial. For those who take conformity with folk intuitions to be at least one