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Vagueness: it is not as if the intended meaning were objectively indeterminate, but that by which it is determined is not in view of our knowledge.
(Vagueness/fuzziness/(s): E.g. If you take away the object that you see blurrily, the blurriness does not remain.)
Die Grenzen vernünftigen Fragens Stuttgart 1996
Wie kommt der Geist in die Materie? München 2001