|Intensions: intensions are reference objects resulting from a linguistic description, in contrast to the material objects (extensions) that may differ therefrom, whether due to inaccuracies, or by the use of indexical expressions. Examples of intensions are “the oldest person in the room”, “the winner”, “John's favorite quote”, “the one who violates the speed limit”. See also morning star/evening star, extensionality, extension.|
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Intension/classes/quantities/Frege/Russell/WittgensteinVsRussell/WittgensteinVsFrege: both believed they could deal with the classes intensionally because they thought they could turn a list into a property, a function.
Intension/extension/Mathematics/Wittgenstein: in everyday language intension and extension are not interchangeable - E.g. I hate the man in the chair - I hate Mr. Schmitz - on the other hand in mathematics: here, there is no difference between "the roots of the equation x² + 2x + 1 = 0 and "2"- in contrast difference: counting bodies ((s) extension, also writing down) is something different than to determine them with a law ((s) intension) - Wittgenstein: law and extension are completely different - ((s) Physics).
Elementary PropositionVsIntension - (protection of formal logic) - intension/meaning/Tractatus/Flor: irrelevant - it is always about extension.
Vorlesungen 1930-35 Frankfurt 1989
Das Blaue Buch - Eine Philosophische Betrachtung Frankfurt 1984
Tractatus Logico Philosophicus Frankfurt/M 1960