The Lump Sum: A Theory of Modal Parts

Abstract

A lump theorist claims that ordinary objects are spread out across possible worlds, much like many of us think that tables are spread out across space. We are not wholly located in any one particular world, the lump theorist claims, just as we are not wholly spatially located where one's hand is. We are modally spread out, a trans-world mereological sum of world-bound parts. We are lump sums of modal parts. And so are all other ordinary objects. In this paper, I explore lump theory and investigate five arguments against it. These arguments may be the primary reasons why lump theory (as envisioned here) has not been widely accepted--or extensively explored--until now. I maintain that these arguments can be answered, and moreover, that accepting lump theory has distinct advantages, making it a competitive view in its own right.1 Lump theory is just one way of embracing modal parts. Lewis (1986Lewis ( , 1993 accepts modal parts -and trans-world sums of modal parts-but he does not think that such objects are metaphysically interesting or relevant. (See below for an elaboration on how our views differ.) L. A. Paul (2002) andKris McDaniel (2004) argue for distinct views, each of which may be considered a 'modal parts' view, in virtue of the fact that individuals (on Paul's view) have modal properties as parts, or because individuals (on McDaniel's view) wholly exist in more than one possible world. Paul's and McDaniel's views differ from the one I am endorsing here, however, which is discussed in Brian Weatherson ms (n.d.) and(2003), andDavid Kaplan (1979).

Plenitude, Coincidence, and Humility

“…11The ‘path’‐style approach is based on Hawthorne (2006) and on the fullness condition in Yablo (1987, 307) and Yablo (forthcoming). Other plenitudinous pictures are framed in different terms: for example, see Jago (2016) for a bundle‐theoretic version of plenitude, Fine (1982, 1999) for a hylomorphic version, and Wallace (2014, 2019) for a version that treats objects as trans‐world sums of modal parts. Dorr et al (2021) formulate their plenitude principles instead in terms of properties that (in one way or another) characterize objects.…”

Varieties of plenitude

“…The resulting picture is a version of plenitude that maintains analogies between a family of permissivist theses about synchronic, diachronic, and modal composition, but in so doing builds in a more contentious background metaphysics than many permissivists will want to endorse. (See Wallace () for further discussion.) Korman () also presents and responds to a modalization of the vagueness argument that is formulated as a more direct analog of Sider's argument for diachronic universalism .…”