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David H. Sanford

Pages 538 - 540

Starting with overlaps as primitive, we can define part as follows: x is part of y if and only if everything that overlaps x also overlaps y. Something that overlaps nothing, according to this definition, is part of everything. To avoid this and similar strange consequences, the domain of mereology is properly restricted to items – call them ‘overlappers’ – that overlap something. (Every overlapper overlaps itself.) Although this made-up term appears only in this paragraph, readers may assume that colorless words such as ‘thing’, ‘everything’, and so forth, refer to overlappers.

1Department of Philosophy, Duke University

1 Cartwright, R., (1975), “Scattered Objects”, as reprinted in his Philosophical Essays, 1987, Cambridge, MIT Press, 171-86.

2 Lewis, D., (1991), Parts of Classes, Oxford: Blackwell.

3 Sanford, D. H., (2003), “Fusion Confusion”, Analysis 63: 1-4.

4 Sanford, D. H., (2011), “Can a Sum Change its Parts?”, Analysis 71: 235-9.

5 Simons, P., (1987), Parts: A Study in Ontology, Oxford: Clarendon Press.

6 Tarski, A., (1929), “Foundations of the Geometry of Solids” as reprinted in his Logic, Semantics, Metamathematics, Oxford: Oxford University Press, 1959: 24-29.

7 Van, Cleve, J., (2008), “The Moon and Sixpence: A Defence of Mereological Universalism”, in Sider, T. et. al. (eds.) Contemporary Debates in Metaphysics, Oxford: Blackwell: 321-40.

8 van, Inwagen, P., (1990), Material Beings, Ithaca: Cornell U. P.

9 van, Inwagen, P., (2006), “Can Mereological Sums Change their Parts?”, The Journal of Philosophy 103: 614-30.

10 Wiggins, D., (1980), Sameness and Substance, Cambridge, Harvard U. P.


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