FOM: supervaluationism and LEM

[Neil Tennant]

Thanks to Hartry for the clarification of why he asserts excluded
middle in the case of vague sentences. Supervaluationism may work for
vague predicates like "bald"; but the question was raised in
connection with mathematical statements like GC and CH. Are we not
owed a convincing case as to why the latter should be assimilated to
those natural language sentences employing vague predicates for which
supervaluationism might be plausible?

In GC and CH all the concepts employed seem clear. A predicate like
"natural number" isn't going to have borderline cases the way "bald"
does. Has supervaluationism ever been advanced before in the case
where the primitive predicates admit of no borderline cases, but where
the syntactic construction of sentences out of them somehow makes them
indeterminate in truth-value?

Neil Tennant