##  [Medial Law](/medial-law) 

  ##  [Medial Law](https://puremath.quantumdictionary.io/medial-law-0) 

  

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- Mathematics & Logic -

**Pure Mathematics Dictionary**

 







 

 

 

 



 

 

 

 

Definition

A binary operation * on a set satisfies the medial (or entropic) law if for all elements a,b,c,d one has (a*b)*(c*d) = (a*c)*(b*d). This identity forces a pairwise interchangeability in double products and is central to the structure theory of medial quasigroups and semigroups.