Consider two object / variable A and B.
In reality A = f(B) & B = f(A).
Imagine an invisible sheet separating the functions mutual dependence.
In one universe, people may see A = f(B) and in other universe B = f(A).
So a person in universe 1 may perceive A to change with respect to B. For him B is not dependent on A.
Similarly a person in universe 2 may perceive B to change with respect to A. For him A is not dependent on B.
The sheet which hides the actual mutual dependence has yet to be ascertained.
civamblog 