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  "body": "\n## Statement\n\nIn classical logic, for each [[proposition|0ZGC7ZESYN]] $p$, the proposition $\\neg \\neg p$ is [[logically equivalent|06GYGS41JK]] to $p$.\n$$\\neg \\neg p \\equiv p$$\n\n## Remarks\n\nThe implication $p \\to \\neg \\neg p$ is also valid in intuitionistic logic.\nThe other direction, $\\neg \\neg p \\to p$, needs classical logic.\nThis direction is the basis of [[proof by contradiction|0J0XBKG64S]].\n\n## Explanations\n\n### L1 human\n\n\"It is not true that $5$ is not prime\" says the same as \"$5$ is prime\".\nTwo negations cancel each other.\n",
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