In this argument Aristotle seems to introduce as a phainomenon that nature exhibits regularity, so that the parts of nature come about in patterned and regular ways. Thus, for instance, humans tend to have teeth arranged in a predictable sort of way, with incisors in the front and molars in the back. He then seems to contend, as an exhaustive and exclusive disjunction, that things happen either by chance or for the sake of something, only to suggest, finally, that what is ‘always or for the mo