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Single Idea 8694

[filed under theme 4. Formal Logic / E. Nonclassical Logics / 6. Free Logic ]

Full Idea

Free logic is especially designed to help regiment our reasoning about fictional objects, or nonexistent objects of some sort.

Gist of Idea

Free logic was developed for fictional or non-existent objects

Source

Michèle Friend (Introducing the Philosophy of Mathematics [2007], 3.7)

Book Ref

Friend,Michèle: 'Introducing the Philosophy of Mathematics' [Acumen 2007], p.77


A Reaction

This makes it sound marginal, but I wonder whether existential commitment shouldn't be eliminated from all logic. Why do fictional objects need a different logic? What logic should we use for Robin Hood, if we aren't sure whether or not he is real?


The 8 ideas with the same theme [logic with no existence commitment for the quantifiers]:

So-called 'free logic' operates without existence assumptions [Meinong, by George/Van Evra]
A 'free' logic can have empty names, and a 'universally free' logic can have empty domains [Bostock]
Free logic at least allows empty names, but struggles to express non-existence [Bach]
Free logic is one of the few first-order non-classical logics [Priest,G]
Same say there are positive, negative and neuter free logics [Read]
Free logic terms aren't existential; classical is non-empty, with referring names [Beall/Restall]
Free logic was developed for fictional or non-existent objects [Friend]
Free logics has terms that do not designate real things, and even empty domains [Anderson,CA]