Let

be a vector in

, where each component is the value on a face of the cube. It is easy to define the linear transformation

that represents a turn. The vector space

can be decomposed into three

-invariant subspaces:

= {

| all faces have the same value},

={

| the sum of all faces is zero and opposite faces have the same value}, and

={

| the sum of all faces is zero and opposite faces also sum to zero}. Examining the action of

on each subspace makes the reasons for the convergence to the average value clear.