 ##  [Law of Excluded Middle](/law-excluded-middle) 

  ##  [Law of Excluded Middle](https://natural.quantumdictionary.io/law-excluded-middle-0) 

  
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**Natural &amp; Formal Sciences Dictionary**

 
Definition

A logical principle that for any proposition P asserts that either P is true or its negation ¬P is true, with no third option (formally: P ∨ ¬P).

 
 ##  [Law of Excluded Middle](https://mathlogic.quantumdictionary.io/law-excluded-middle-1) 

  
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- Natural &amp; Formal Sciences -

**Mathematics &amp; Logic Dictionary**

 
Definition

The principle that for any proposition P, the disjunction P ∨ ¬P is true; there is no third truth-value between a proposition and its negation in classical logic.