 ##  [Disjunction Introduction](/disjunction-introduction) 

  ##  [Disjunction Introduction](https://mathlogic.quantumdictionary.io/disjunction-introduction-0) 

  
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- Natural &amp; Formal Sciences -

**Mathematics &amp; Logic Dictionary**

 
Definition

An inference rule that allows one to infer a disjunction A ∨ B from a proof of one of its disjuncts (from A infer A ∨ B, or from B infer A ∨ B).