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4. Formal Logic / E. Nonclassical Logics / 8. Intensional Logic

[logic that includes meanings and concepts, as well as objects]

3 ideas
If terms change their designations in different states, they are functions from states to objects [Fitting]
     Full Idea: The common feature of every designating term is that designation may change from state to state - thus it can be formalized by a function from states to objects.
     From: Melvin Fitting (Intensional Logic [2007], 3)
     A reaction: Specifying the objects sounds OK, but specifying states sounds rather tough.
Intensional logic adds a second type of quantification, over intensional objects, or individual concepts [Fitting]
     Full Idea: To first order modal logic (with quantification over objects) we can add a second kind of quantification, over intensions. An intensional object, or individual concept, will be modelled by a function from states to objects.
     From: Melvin Fitting (Intensional Logic [2007], 3.3)
Intensional logic maps logical space, showing which predicates are compatible or incompatible [Magidor]
     Full Idea: Intensional logic aims to capture necessary relations between certain predicates, such as that 'green all over' and 'red all over' cannot be co-instantiated. Each predicate is allocated a set of points in logical space, and every object has one point.
     From: Ofra Magidor (Category Mistakes [2013], 4.4)
     A reaction: This produces an intriguing model of reality, as a vast and rich space of multiply overlapping modal predicates. Things can be blue, square, dangerous and large. They can't be small and large, or square and round. Objects are optional extras!