Concept tag
#metaphysical-necessity
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S5 is the right logic for metaphysical necessity
Here is a view I hold about modal logic and want tested. S5 says: whatever is possible is necessarily possible, and whatever is necessary is necessarily necessary. In Kripke's terms, every world is accessible from every other. For metaphysical necessity (what could…
Started by Tomasz Szewczak6 replies -
My daughter asked whether a square circle could exist on another planet. How do I answer?
My nine-year-old has decided that "anything could be true somewhere in space". Last week it was square circles, this week it is a planet where two and two make five. I said no, and she asked why a planet with no gravity…
Started by Thamarai Raman4 replies