  Extrinsic changes aren't “real” in the sense above. I change extrinsically when a dog comes to be on my left. The dog does not so act on me at to make me have it on my left: the dog does nothing to me at all. And my becoming a man with a dog on his left could not be the only event in a universe. For it to happen, a dog must also move. But to say that extrinsic changes aren't “real” in the above sense is not to say that they don't occur. It is merely to classify them.