|Extension, philosophy: an object, for example, the planet Venus as a material body, independent from the manner in which it is singled out. In contrast, intension is the way in which the object is given or is represented, e.g. Morning star or Evening star. See also intensions, identity, identity conditions, reference, meaning, assertibility conditions, propositional attitudes, opacity.|
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Extension/Putnam: "I" has no extension but extension function - intension/new: (Montague/Carnap): we associate with the term "cat" a function f (M), whose value at every possible world M is the number of possible objects that are cats in the world M - intension (new): indicates how the extension depends on worlds.
Extension unequal meaning/new: since logically equivalent terms in each world have the same intension and therefore also the same extension - meaning (old intension) does not remain with equivalence: E.g. cube, 6 polyhedra - in each possible world the same object - difference in meaning would be lost.
Von einem Realistischen Standpunkt Frankfurt 1993
Repräsentation und Realität Frankfurt 1999
Für eine Erneuerung der Philosophie Stuttgart 1997
Pragmatismus Eine offene Frage Frankfurt 1995
Vernunft, Wahrheit und Geschichte Frankfurt 1990