Some philosophers find it important or at least expedient esatto frame the issue sopra terms of the case of per statue \(s\) and piece of clay \(c\) that coincide throughout their entire existence. We bring both \(c\) and \(s\) into existence by joining two other pieces of clay together, or we do something else that guarantees total coincidence. It seems that total coincidence is supposed onesto lend plausibility sicuro the claim that, per such verso case at least, constitution is identity (and hence NI is false – Gibbard 1975). For example, \(s\) may be admired for its aesthetic traits, even long after it ceases preciso exist, but this need not be true of \(c\). And \(s\) has the property, which \(c\) lacks, of being destroyed if squeezed into a ball. Those who defend the thesis that constitution is identity need sicuro defend it in the general case of partial coincidence; and those who attack the thesis do so with arguments that rete informatica equal well against both total and partial coincidence. The assumption that \(s\) and \(c\) are totally coincident is therefore inessential.
The doctrine of temporal parts offers only limited help. The statement that \(c\) is identical puro \(s_1\)on day 1 but identical to \(s_2\) on day 2 can be construed onesto mean that \(c\) is a temporally extended object whose day 1 stage is identical sicuro \(s_1\) and whose day 2 tirocinio is identical onesto \(s_2\). Similarly, we can regard \(s_2\) as a temporally extended object that overlaps \(c\) on day 2 and \(c’\) on day 3. But unless temporal parts theorists are prepared puro defend verso doctrine of modally extended objects – objects extended through possible worlds analogous sicuro objects extended durante time, there remains verso problem. \(s_2\) might have been made of per different piece of clay, as is mediante fact the case on day 3. That is, it is logically possible for \(s_2\) to mobili caribbeancupid fail onesto coincide with the day 2 stage of \(c\). But it is not logically possible for the day 2 stage of \(c\) onesto fail to coincide with itself.
Since the two stages are not identical, NI does not apply
Lewis recognizes this difficulty and proposes puro deal with it by appealing preciso his counterpart theory (Lewis 1971, 1986, and 1993). Different concepts, di nuovo.g., statue and piece of clay are associated with different counterpart relations and hence with different criteria of trans-world identity. The property determined by per modal predicate may be affected by the subject term of verso sentence containing the predicate. The subject term denotes an object belonging onesto this or that kind or sort. But different kinds or sorts may determine different properties (or different counterpart relations). Durante particular, the properties determined by the predicate ‘might not have coincided with \(c_2\)’ (where \(c_2\) names the day 2 tirocinio of \(c)\) in the following sentences,
This has the effect of rendering modal predicates “Abelardian” (Noonan 1991, 1993)
- \(s_2\) might not have coincided with \(c_2\),
- \(c_2\) might not have coincided with \(c_2\),
are different, and hence (a) and (b) are compatible, even assuming that \(s_2\) and \(c_2\) are identical. (It should be emphasized that counterpart theory is not the only means of obtaining Abelardian predicates. See Noonan 1991.)
The upshot seems onesto be that that the advocate of the canone account of identity must maintain either that constitution is not identity or that modal predicates are Abelardian. The latter option may be the fruitful one, since for one thing it seems to have applications that go beyond the issue of constitution.