Vagueness and Fuzziness

Probability theorists tend to think that everything that fuzzy logic can do it (probability theory) can do better. But probability theory is a procedure for dealing with uncertainty. Perhaps some things are vague -- legal language, for example -- without being uncertain. So perhaps the question of the legitimacy of fuzzy logic boils down to the question of the existence or non-existence of vague objects that are not necessarily uncertain.

But perhaps fuzzy logic also legitimately applies to reasoning about uncertain propositions -- because perhaps some or much reasoning about uncertain propositions involves vague objects (concepts). Be that as it may, perhaps it is true that fuzzy logic will gain a greater measure of respectability among standard probability theorists if the distinction between uncertainty and vagueness is solidified.

N.B. It may be true that vague concepts -- e.g., vague legal concepts -- work in ways that are uncertain to some degree. But does it follow that such (vague) legal concepts are "uncertain" to some degree? This is perhaps a nice test question for logicians and legal theorists.

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