diff --git a/docs/user_guide/operators.rst b/docs/user_guide/operators.rst
index 9499562f2..ec28e2fba 100644
--- a/docs/user_guide/operators.rst
+++ b/docs/user_guide/operators.rst
@@ -89,9 +89,12 @@ registered from numpy are located in ``graphblas.binary.numpy``.
 Monoids
 -------
 
-Monoids extend the concept of a binary operator to require a single domain for all inputs and
-the output. Monoids are also associative, so the order of the inputs does not matter. And finally,
-monoids have a default identity such that ``A op identity == A``.
+Monoids extend the concept of a binary operator to require a single domain for all inputs and the output.
+Monoids are also associative so the order of operations does not matter
+(for example, ``(a + b) + c == a + (b + c)``).
+GraphBLAS primarily uses *commutative monoids* (for example, ``a + b == b + a``),
+and all standard monoids in python-graphblas commute.
+And finally, monoids have a default identity such that ``A op identity == A``.
 
 Monoids are commonly for reductions, collapsing all elements down to a single value.