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  "body": "\n## Summary\n\nKripke semantics interprets [[modal logic|C3RZY20ETK]] in a set of possible worlds linked by an accessibility relation.\nA formula $\\square\\varphi$ is true at a world when $\\varphi$ is true at every world accessible from it.\nMany modal logics are exactly the sets of formulas valid on a class of such frames.\nA variant of the semantics also serves [[intuitionistic logic|Q11N8X99FK]].\n\n## Explanations\n\n### L1 human\n\nPicture a set of points, the possible worlds, with arrows between some of them.\nAt each world, each basic statement is either true or false.\n\"Necessarily $p$\" holds at a world when $p$ holds at every world that its arrows reach.\nFor example, with two worlds $u \\to v$, where $p$ is true only at $v$, the formula $\\square p$ holds at $u$, but $p$ itself does not.\n",
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