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  "body": "\n## Summary\n\nIn modal logic, **modal collapse** is the condition in which every true statement is necessarily true, and vice versa; that is to say, there are no contingent truths, or to put it another way, that \"everything exists necessarily\" (and likewise if something does not exist, it cannot exist). In the notation of modal logic, this can be written as $\\phi \\leftrightarrow \\Box \\phi$.\n",
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