- Various objections to indeterminate identity are not conclusive.
- Quine's doctrine "No entity without identity" rules out only entities for which identity does not make sense; it is not aimed at indeterminacy.
- Holding on to bivalence for methodological reasons is not compelling, since little of methodological value is lost in allowing that claims may lack truth-value, and many physicists have (rightly or wrongly) adopted this stance towards some phenomena in quantum mechanics2 without hampering their methodology.
- Even if bivalence is maintained within each science, identity puzzles may still arise where sciences overlap. An argument of Salmon's is reviewed; it is either a version of Evans's argument, already discussed, or a challenge to indeterminate set theory, discussed in Chapter 113.
- Sometimes puzzles arise from reading sentences non-literally.
These options account for data used by some writers in an attempt to refute indeterminate identity.
- A sentence may be read supervaluationally: it is treated as true (false) if all ways of making its vocabulary determinate yield readings which are true (false).
- It may also be read super-resolutionally: it is treated as true (false) if all worlds that result from some way of making our own world completely determinate would make the sentence true (false).
- A purported refutation of non-bivalence by Williamson is discussed; it is argued that his claims that all contradictory sentences must be false are plausible only if they are read in some special way, e.g. supervaluationally.
- Several authors point out that if an object has indeterminate boundaries, this does not logically entail that it is indeterminately identical to something. Some mereological principles are given that would fill in this logical gap. Objects may or may not be subject to these principles. An example due to Cook is alleged to be hypothetically of this kind (given his assumptions); his disproof of indeterminate identity is examined and found to be inconclusive.
- An argument by Noonan against an example (due to John Broome) of indeterminate identity of clubs is shown to be implausible if the claims in it are read literally; those claims are plausible if read super-resolutionally, but then they do not conflict with indeterminate identity.
Footnote 1: Taken from "Parsons (Terence) - Indeterminate Identity: Analytical Table of Contents".
Footnote 3: Ie. In "Parsons (Terence) - Sets and Properties with Indeterminate Identity".
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