 Like most philosophical terms of art which lack official, uncontroversial definitions, the relevant use of ‘natural’ is controversial: many philosophers regard it as too unclear, or too closely tied to some false presupposition, to be helpful. Among this group, some would go so far as to deny that there is any interesting or theoretically important relation holding between the pairs of properties listed in the above table, at least if we set aside relations (like being expressible more briefly than) whose pattern of instantiation would have been different if our interests or practices had been different. On this picture, the very idea that some properties are more natural than others embodies a mistaken projection onto the world itself of differences which are in fact just a matter of the contingent concerns and purposes of human beings.