Vagueness and Identity :: Philosophy Philosophical Papers

Vagueness and Identity ABSTRACT: The view that identity can be vague holds that there are statements of identity which are neither true nor false. The view that composition can be vague holds that unities can have borderline constituents — that is, elements that are neither parts nor non-parts of some larger unity. The case for vague identity is typically made by way of an argument for the vagueness of composition. In this paper, however, I argue that the thesis that composition can be vague is actually incompatible with the thesis of vague identity. The argument for the incompatibility of these two views arises out of a demonstration of the way in which constituency facts (even vague constituency facts) are grounded in the other facts about how a larger unity is configured. Thus, I show that composites that are allegedly vaguely identical are actually different configurations. Hence, the alliance of vague composition with vague identity is taken to be all that is needed in order to show that compos itional vagueness is indefensible. I It is sometimes held that, like other things, identity can be vague.But care should be taken about what this means. The claim that identity can be vague is best understood as the claim that there can be statements of identity which are indeterminate in truth value. This view gains in attractiveness when the precision of the concept of identity is contrasted with the lack of precision endemic to various criteria of identity. As Sainsbury notes, diachronic artifact identity must surely be governed by principles such as this: "Replacing some, but not too many, parts of an artifact does not destroy it, but leaves the very same artifact". Such principles are vague. How could the identity relation, which they determine, be precise? Considerations like these extend to members of natural kinds like mountains and cows as well. What's consistent throughout these views is that identity requires enough of the appropriate sort of continuity. This reliance on continuity goes for not only the way w e re-identify things over time, but for the way we individuate objects at a time as well. So for example, spatio-temporal continuity at least partially explains how it is that at Broadway and 42nd I am standing on the same road I stood on when I was at Broadway and 41st. Since identity deciding conditions like continuity and contiguousness can be weak or strong or more or less, it appears the vagueness of those concepts has a limiting effect on how precise identity claims can be.