Entropic algebra

Summary

An entropic algebra is an algebra in which any two operations commute with each other. Equivalently, every operation $A^n \to A$ is a homomorphism of algebras from the power $A^n$ to $A$. For an algebra with one binary operation this is the medial law. Modules over a commutative ring, semilattices and affine spaces are entropic. In an entropic variety, the homomorphisms from one algebra $A$ to another algebra $B$ form a subalgebra of the power $B^A$.