{
  "aliases": [
    "alternative-denial",
    "inclusive-nand",
    "logical-nand",
    "nand-operator",
    "scheffers-stroke",
    "sheffer-connective",
    "sheffers-stroke"
  ],
  "backlinks": null,
  "body": "\n## Summary\n\nIn [[Boolean functions|0A58THH5XV]] and propositional calculus, the **Sheffer stroke** denotes a logical operation that is equivalent to the negation of the [[conjunction|025YZN3VJW]] operation, expressed in ordinary language as \"not both\". It is also called **non-conjunction**, **alternative denial** (since it says in effect that at least one of its operands is false), or **NAND** (\"not and\"). In digital electronics, it corresponds to the NAND gate. It is named after Henry Maurice Sheffer and written as $\\mid$ or as $\\uparrow$ or as $\\overline{\\wedge}$ or as $Dpq$ in Polish notation by Łukasiewicz (but not as ||, often used to represent [[disjunction|0F72FK8EKB]]).\n",
  "commit": "4a3290d299c8b2cd6493fce2296920ba7f82d942",
  "front": {
    "aliases": [
      "alternative-denial",
      "inclusive-nand",
      "logical-nand",
      "nand-operator",
      "scheffers-stroke",
      "sheffer-connective",
      "sheffers-stroke"
    ],
    "inventory": [
      "37N3PZJH03"
    ],
    "kind": "concept",
    "name": "Sheffer stroke",
    "same_as": {
      "wikidata": "Q3874243",
      "wikipedia": "Sheffer stroke"
    },
    "sources": [
      {
        "locator": "Sheffer stroke",
        "mention": "wikipedia://en/29388",
        "note": "adopted",
        "sections": [
          "Summary"
        ],
        "wikipedia": "en:29388@r1375830657"
      }
    ],
    "tag": "1NNYWRN6B8"
  },
  "kind": "concept",
  "link": "https://math2.tamnd.com/node/1NNYWRN6B8/",
  "links": null,
  "markdown": "https://math2.tamnd.com/node/1NNYWRN6B8.md",
  "msc": null,
  "name": "Sheffer stroke",
  "prov": null,
  "role": "",
  "source": "https://github.com/tamnd/math2/blob/main/nodes/1NN/1NNYWRN6B8.md",
  "status": null,
  "tag": "1NNYWRN6B8",
  "uri": "m2://1NNYWRN6B8",
  "url": "https://math2.tamnd.com/wiki/sheffer-stroke/",
  "writing": {
    "tag": "1NNYWRN6B8",
    "kind": "concept",
    "level": "W1",
    "next": [
      {
        "what": "edge defines in",
        "note": "at least one definition",
        "have": 0,
        "want": 1
      },
      {
        "what": "edge instance_of in",
        "note": "at least two examples",
        "have": 0,
        "want": 2
      },
      {
        "what": "edge not_instance_of in",
        "note": "at least one non-example",
        "have": 0,
        "want": 1
      },
      {
        "what": "edge specializes both",
        "note": "the more general notions and the special cases",
        "have": 0,
        "want": 1
      }
    ]
  }
}