Why Sense Cannot be Made of Vague Identity
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In this paper I present a new argument against vague identity --- one that
is more fundamental than existing arguments --- and I also try to explain
why we find the idea of vague identity puzzling, in a way that will dispel
the puzzlement. In brief, my argument is this: to make clear sense of
something, one must at least model it set-theoretically; but due to the
special place of identity in set-theoretic models, any vague relation that
one does model set-theoretically will not be identity, for real identity
will already be there, built into the background of the model, and
perfectly precise.