{
  "aliases": null,
  "backlinks": null,
  "body": "\n## Definition\n\nLet $\\Gamma$ be a set of [[formulas|HYJ10AF6RT]] and $\\varphi$ a formula, all over the same signature.\nThen $\\varphi$ is a *logical consequence* of $\\Gamma$, written $\\Gamma \\models \\varphi$, if every interpretation that makes every formula of $\\Gamma$ true also makes $\\varphi$ true.\nIn [[propositional logic|09K9MWD2QQ]] an interpretation is a truth assignment to the variables.\nIn first-order logic it is a [[structure|983GZBQYT4]] together with an assignment of its elements to the variables.\n\n## Remarks\n\n$\\set{p, \\; p \\to q} \\models q$: in every assignment where $p$ and $p \\to q$ are true, $q$ is true by the truth table of $\\to$.\n$\\set{p \\to q, \\; q} \\not\\models p$: the assignment $p = \\mathsf{F}$, $q = \\mathsf{T}$ makes both premises true and $p$ false.\n$\\emptyset \\models \\varphi$ means that $\\varphi$ is valid, written $\\models \\varphi$.\n$\\Gamma \\models \\varphi$ holds exactly when $\\Gamma \\cup \\set{\\neg \\varphi}$ is not [[satisfiable|QN7M1JCGT9]].\n",
  "commit": "547b6eddb8f2feb8d579f2d633d22a27b7e132fc",
  "front": {
    "defines": "1HK0VYWTV7",
    "kind": "definition",
    "msc": [
      "03B05",
      "03B10"
    ],
    "name": "Logical consequence",
    "sources": [
      {
        "url": "https://en.wikipedia.org/wiki/Logical_consequence"
      }
    ],
    "tag": "KKNB9JY1YH",
    "uses": [
      "09K9MWD2QQ",
      "HYJ10AF6RT",
      "983GZBQYT4"
    ]
  },
  "kind": "definition",
  "link": "https://math2.tamnd.com/node/KKNB9JY1YH/",
  "links": [
    {
      "field": "defines",
      "target": "1HK0VYWTV7"
    },
    {
      "field": "uses",
      "target": "09K9MWD2QQ"
    },
    {
      "field": "uses",
      "target": "HYJ10AF6RT"
    },
    {
      "field": "uses",
      "target": "983GZBQYT4"
    }
  ],
  "markdown": "https://math2.tamnd.com/node/KKNB9JY1YH.md",
  "msc": [
    "03B05",
    "03B10"
  ],
  "name": "Logical consequence",
  "prov": null,
  "role": "",
  "source": "https://github.com/tamnd/math2/blob/main/nodes/KKN/KKNB9JY1YH.md",
  "status": null,
  "tag": "KKNB9JY1YH",
  "uri": "m2://KKNB9JY1YH",
  "url": "https://math2.tamnd.com/wiki/logical-consequence-definition/",
  "writing": {
    "tag": "KKNB9JY1YH",
    "kind": "definition",
    "level": "W0",
    "next": [
      {
        "what": "an inventory row",
        "note": "the row of the inventory that the node accounts for",
        "have": 0,
        "want": 1
      },
      {
        "what": "a source with a locator",
        "have": 0,
        "want": 1
      }
    ]
  }
}
