dhw: Something went wrong at the end of your post, but the basis seems clear to me. Obviously entropy does not explain how order comes out of disorder, so entropy is not the whole story, and if cause and effect are used as criteria for time's arrow, one cannot say that time would not exist if the universe hadn't been in perfect order to start with. - My writing program acts up at times. Sorry. Basically the universe is running down to end one day, entropy in action.