 ##  [Nonmonotonic Reasoning](/nonmonotonic-reasoning) 

  ##  [Nonmonotonic Reasoning](https://mathlogic.quantumdictionary.io/nonmonotonic-reasoning-0) 

  
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- Natural &amp; Formal Sciences -

**Mathematics &amp; Logic Dictionary**

 
Definition

A class of inferential processes in which adding new premises can invalidate previously drawn conclusions; inference is defeasible rather than strictly monotonic.