What is vagueness and how does it differ from ambiguity and uncertainty?

Vagueness is manifested through predicates that admit borderline cases, namely cases where it is unclear whether or not the predicate applies. For example, some people are borderline tall: not clearly tall and not clearly not tall. Alternatively, vagueness is related to the absence of sharp boundaries. For example, on a scale of heights, there appears to be no sharp boundary between the tall people and the rest.

Vagueness is not the same phenomenon as that of ambiguity or uncertainty. For example, the truth of an uncertain statement, such as “Tomorrow the temperature might rise to 27 degrees,” cannot be determined due to lack of adequate information about it, not because the measurement of temperature lacks sharp boundaries. Also, the truth of a statement might not be determinable due to the ambiguity of some term (e.g., in statement “Yesterday we went to the bank” the term bank is ambiguous), yet, again, this does not make the statement vague.

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