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Nonexistence/Unicorn-Example/Truth-value gap/Frege: E.g. Unicorn: sentence without truth value - predicates can not be switched on or denied - the thought is the same whether the name refers ("meaning", reference) or not.
Name/Non-existence/Frege/Husted: that the name has a reference is not a condition that it belongs to the language - but vice versa.
Nonexistence/Meaning/Meaning/FregeVsMeinong/FregeVsRussell: there are quite a lot contradictory terms - only no contradictory objects - the logic may determine only the limitation of terms - that is, for each object, whether it falls within the definition, or not - a contradictory term is used to prove that there is no corresponding object.
Nonexistence/Frege: proper names: a name that refers to nothing, is logically meaningless - but not a concept under which nothing falls - for a name to be entitled it is necessary that the appropriate term is sharp.
Therefore the term should precede the scope.
Die Grundlagen der Arithmetik Stuttgart 1987
Funktion, Begriff, Bedeutung Göttingen 1994
Logische Untersuchungen Göttingen 1993