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Edward Jonathan Lowe

Pages 147 - 150

Can two material objects exist in the same place at the same time? In other words, is a case of material coincidence possible? Few philosophers would want to say that two material objects of the same kind can coincide, such as two ships or two lumps of copper (Oderberg 1996 denies that they can, but Hughes 1997 takes an opposing view). However, many would say that material objects of suitably different kinds, with different persistence conditions, can coincide, such as a lump of copper and a copper statue ‘constituted’ by that lump (Wiggins 2001 defends this position). Yet this view apparently conflicts with widely-held principles of mereology – in particular, both the weak and the strong principles of extensionality. The weak principle states that composite objects with exactly the same proper parts are identical, while the strong states that composite objects with exactly the same proper parts at some level of decomposition are identical. (The strong principle entails the weak, but not vice versa). It might perhaps be denied that the copper statue and the lump of copper have exactly the same proper parts, on the grounds that it is counterintuitive to say, for example, that the head of the statue is a proper part of the lump (see Lowe 2001). However, it seems clear that they do have the same proper parts at the level of their composition by copper particles: the statue and the lump are composed by exactly the same copper particles, at any time at which the former could be said to be ‘constituted’ by the latter. So aren’t we required to say that in this case constitution is identity with the consequence that, after all, the statue and the lump must have exactly the same parts? Perhaps not, since we may prefer to see this case as a counterexample to the strong principle of extensionality.

1Department of Philosophy, Durham University

1 Burke, M. B., (1994a), “Preserving the Principle of One Object to a Place: A Novel Account of the Relations among Objects, Sorts, Sortals, and Persistence Conditions”, Philosophy and Phenomenological Research 54: 591-624.

2 Burke, M. B., (1994b), “Dion and Theon: An Essentialist Solution to an Ancient Puzzle”, Journal of Philosophy 91: 129-39.

3 Gallois, A., (1998), Occasions of Identity: The Metaphysics of Persistence, Change, and Sameness, Oxford: Clarendon Press.

4 Hughes, C., (1997), “Same-Kind Coincidence and the Ship of Theseus”, Mind 106: 53-67.

5 Lewis, D. K., (1983), “Survival and Identity”, in his Philosophical Papers Volume 1, New York: Oxford University Press.

6 Lowe, E. J., (2001), “Identity, Composition, and the Simplicity of the Self”, in Corcoran, K. (ed.) Soul, Body, and Survival: Essays on the Metaphysics of Human Persons, Ithaca, NY: Cornell University Press.

7 Lowe, E. J., (2003), “Substantial Change and Spatiotemporal Coincidence”, Ratio 16: 140-60.

8 Noonan, H. W., (1991), “Constitution is Identity”, Mind 102: 133-46.

9 Oderberg, D. S., (1996), “Coincidence under a Sortal”, Philosophical Review 105: 145-71.

10 Olson, E. T., (2001), “Material Coincidence and the Indiscernibility Problem”, Philosophical Quarterly 51: 337-55.

11 Thomson, J. J., (1998), “The Statue and the Clay”, Noûs 32, 149-73.

12 van, Inwagen, P., (1981), “The Doctrine of Arbitrary Undetached Parts”, Pacific Philosophical Quarterly 62: 123-37.

13 Wiggins, D., (2001), Sameness and Substance Renewed, Cambridge: Cambridge University Press.


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