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- John Divers (2006). Possible-Worlds Semantics Without Possible Worlds: The Agnostic Approach. Mind 115 (458):187-226.If a possible-worlds semantic theory for modal logics is pure, then the assertion of the theory, taken at face-value, can bring no commitment to the existence of a plurality of possible worlds (genuine or ersatz). But if we consider an applied theory (an application of the pure theory) in which the elements of the models are required to be possible worlds, then assertion of such a theory, taken at face-value, does appear to bring commitment to the existence of a plurality of possible worlds. Or at least that is so if the applied theory is adequate. For an applied possible-worlds semantic theory that is constrained to contain only one-world models is bound to deliver results on validity, soundness and completeness that are apt to seem disastrous. I attempt to steer a course between commitment to the existence of a plurality of possible worlds and commitment to such a disastrous applied possible-worlds semantics by noting, and developing, the position of one who asserts such a theory at face-value but who remains agnostic about the existence of other (non-actualized) possible worlds. Thus, a novel interpretation of applied possible-worlds semantics is offered on which we may lay claim to whatever benefits such a theory offers while avoiding realism about (other) possible worlds. Thereby, the contention that applied possible-worlds semantics gives us reason to be realists about possible worlds is (further) undermined.
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Discussion of John Divers, Possible-worlds semantics without possible worlds: The agnostic approach
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| 2009-12-17 | |
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Rodrigo Cid
Universidade Federal do Rio de Janeiro |
When we say that "P" is possible iff there is a possible world where "P" is true, we can continue and say that there is a possible world where "P" is true iff "A" is true, and "A" is not something about a non-actual possible world. Such an approach would allow us to use the vocabulary of possible worlds, while sustaining an agnostic or an anti-realist position about the the existence of non-actual possible worlds. Can such a reductive approach to possible worlds solve the problem of
ontological commitmentt to the existence of non-actual possible worlds? And what do you think that "A" must be as non-actual possible worlds dont get implicated?
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