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Continue to ChatSet-theoretic mereology: the theory of the subset relation is decidable https://jdh.hamkins.org/set-theoretic-mereology-the-theory-of-the-subset-relation-is-decidable/
Set-theoretic mereology: the theory of the subset relation is decidable https://jdh.hamkins.org/set-theoretic-mereology-the-theory-of-the-subset-relation-is-decidable/