Notes
Perhaps all our intuitions are vague and subjective, but more so for modal notions. If determining truth in this world is elusive, how much more elusive must it be to ponder it in “possible” or “possibly possible” worlds? Who is to pronounce what is logically possible or necessary? Kripke has famously argued that it is logically necessary that every person has the parents that he or she has, so that in every possible world you and I have the exact same parents that we have in this world, because that is part of our essence. But different people have radically different intuitions on such matters; how can we adjudicate?
A number of widely divergent analyses have been offered, but none manages to combine clarity with prima facie plausibility.
For instance, see Hughes and Cresswell (1996, p. 243).
We can ignore accessibility relations, since they are not necessary for the semantics of S5.
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Commentary on Bringsjord on P = NP. Minds & Machines 27, 673–678 (2017). https://doi.org/10.1007/s11023-017-9452-3
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DOI: https://doi.org/10.1007/s11023-017-9452-3