  Reacting, in part, to Leopold’s call for a “land ethic”, Sylvan’s subsequent work in the area (much of the early work with Val Routley, later Val Plumwood) proceeds to describe and argue for just such a non-anthropocentric, environmental ethic. A dominant aspect of this “new” ethic (indeed, a characterising feature in Elliot 1980) that was fixed on by subsequent authors was the extension of non-instrumental, “intrinsic” or “final” values to the non-human world. First mentioned in 1974 in early drafts of Routley and Routley (1980a) and subsequently Val Routley (1975), Rolston (1975), and Callicott (1979)—who all employ versions of the Last Man Example—the extension is described and defended at length in Routley and Routley (1980a). (Sylvan assumes intrinsic value is, in general, already assured on the familiar Aristotelian ground that instrumental value requires intrinsic value, lest vicious regress ensue—cf. Aristotle Metaphysics, 994b9–15.)