Gregory Bateson used the analogy of a man cutting down a tree with an axe (Bateson, 1991, p 164) to explain the system- based nature of reality.
He points out that in order to swing the axe, the man needs to pay attention to where the last cut was. The cut, it could be said, causes him to swing in a certain place. And each cut could also be said to result from the specific properties of the axe; how heavy it feels, and how well balanced. So the axe, it might be claimed, controls the cut, which controls the man.
Actually, of course, Bateson is claiming that the tree-cutting is a system, and that cause and effect descriptions of it may be useful for communication, but have little use scientifically. Even the arbitrary divisions between man, axe and tree merely simplify in ways which suit our communication style.