Things may be split into natural and non-natural. In turn, the natural things may exist either in nature or in society; and the unnatural things may be artificial like books or supernatural like gods. Naturalism is the philosophical view, first advanced by Thales of Miletus, that the universe and nature are the same, so that there is nothing supernatural and nothing irreducibly social. For example, according to Aristotle (1941: 1253a), "it is evident that the state is a creation of nature, and that man is by nature a political animal."