Nietzsche, in Beyond Good and Evil. (Usually translated a little differently, but the point's basically the same.)

Though I disagree with Nietzsche about very many things, he did have quite the talent at coming up with wonderfully evocative ideas, and this one's a keeper.

Incidentally, I explain in another article why even though I like to make things as simple as possible, it's usually not possible when dealing with human beings who react to other humans who react back etc..