====== Proposition (logic) ======

IN logic, a formal or natural language expression that can either be //true// or //false//.

Examples:

  * “true” -> a proposition with the value //true//.
  * “2 + 3 = 5” -> proposition with the value //true//.
  * “Paris is the capital of France.” -> a proposition which is //true//.
  * “Japan is an island in the Atlantic ocean.” -> a proposition which is //false//.
  * “<s invalid>2 + 3</s>” -> not a proposition, as it has a value (“5”) that is neither //true// nor //false//.
  * “<s invalid>The longest river in Europe</s>” -> not a proposition, as it has a value (“Danube”) that is neither //true// nor //false//.


===== See also =====

  * [[glossary:contradiction|Contradiction]]
  * <i lang="ja-Latn">[[glossary:mu|Mu]]</i>
  * [[glossary:tautology|Tautology]]

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