 However, he rejected the view that we need to abandon the Western tradition of scientific rationalism, and was unsympathetic towards attempts to articulate environmental concern through radical revisions of our ethical framework, as advocated by deep ecologists, which he conceived as misguided mysticism or irrationalism.Passmore was very skeptical about attempts to attribute intrinsic value to nature, and his preferred position was of valuing nature in terms of what it contributes to the flourishing of sentient creatures (including humans).According to William Grey of the International Society for Environmental Ethics, his "unequivocal anthropocentrism made him a reference point in the discourse of environmental ethics and many treatises in field begin with (or include) a refutation of his views."