|Classes: identity of classes provided by same elements (extension) - identity of properties by the same predicates (intension).|
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Classes/Goodman: When are two objects essentially of the same kind? The fact that they both belong to some class is not enough. Because: any pair of objects belongs to some kind of class.
And that bothshould belong exactly to the same class would be asking too much, because two objects never belong to exactly the same classes.
Classification includes preference.
Weisen der Welterzeugung Frankfurt 1984
Tatsache Fiktion Voraussage Frankfurt 1988
Sprachen der Kunst Frankfurt 1997
N. Goodman/K. Elgin
Revisionen Frankfurt 1989