 ##  [Richard's Paradox](/index.php/richards-paradox) 

  ##  [Richard's Paradox](https://mathlogic.quantumdictionary.io/richards-paradox-0) 

  
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- Natural &amp; Formal Sciences -

**Mathematics &amp; Logic Dictionary**

 
Definition

A definability paradox about real numbers: if one attempts to enumerate all real numbers definable in a natural language, one can diagonalize this list to produce a new real number that is itself definable, producing a contradiction that exposes imprecision in informal definability.