##  [Law of Identity](/index.php/law-identity) 

  ##  [Law of Identity](https://mathlogic.quantumdictionary.io/law-identity-0) 

  

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**Mathematics & Logic Dictionary**

 







 

 

 

 



 

 

 

 

Definition

A fundamental logical principle stating that every object or proposition is identical to itself; formalized in predicate logic as the reflexivity axiom x = x for an identity predicate, and in propositional logic as the tautology p ⇒ p (or p ↔ p).