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  "body": "\n## Summary\n\nThe comparability graph of a [[partially ordered set|0QV2JS9RJ3]] joins two elements by an edge when they are comparable.\nA graph is a comparability graph when it arises in this way from some partial order.\nChains become cliques and antichains become independent sets, so order results such as [[Mirsky's theorem|5VPXR3RDF1]] turn into graph results.\nComparability graphs are [[perfect graphs|1YZ7NV161A]].\n\n## Explanations\n\n### L1 human\n\nStart from a poset and forget which element is the smaller one in each related pair.\nWhat remains is an ordinary [[graph|00C0BR7D7H]]: an edge just says \"these two are related\".\nFor the divisors of $6$, the graph has edges $1$–$2$, $1$–$3$, $1$–$6$, $2$–$6$ and $3$–$6$, but no edge $2$–$3$.\n",
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