as it were — ‘a new, an environmental ethic,’ such as Richard Routley had warranted in 1973.” In accordance with Leopold's oft-quoted dictum — "A thing is right when it tends to preserve the integrity, stability, and beauty of the biotic community. It is wrong when it tends otherwise" — Callicott espouses a holistic, non-anthropocentric environmental ethic. What he labels the “extentionist” approach to environmental ethics attempts to extend familiar anthropocentric ethical paradigms — legacies of the European Enlightenment — to other-than-human beings. Peter Singer’s “animal liberation,” for example, extends Jeremy Bentham’s utilitarian ethical paradigm to all sentient animals. Paul W. Taylor's “biocentrism” extends the Kantian deontological paradigm to all “teleological centers of life” (i.e. all organisms). Extensionist approaches, however, are inveterately individualistic, conferring “moral considerability” on individual organisms. Actual environmental concerns, however, focus on transorganismic entities: endangered species; threatened biotic communities and ecosystems; rivers and lakes; the ocean and atmosphere. Callicott believes that an adequate environmental ethic — an environmental-ethics paradigm that addresses actual environmental concerns — must be holistic. Callicott traces the conceptual foundations of the Leopold land ethic first back to Charles Darwin’s analysis of the “moral sense” in the Descent of Man and ultimately to David Hume’s grounding of ethics in the “moral sentiments” espoused in An Enquiry Concerning the Principles of Morals. Hume argues that moral actions and moral judgments are based on such other-oriented sentiments as sympathy, beneficence, loyalty, and patriotism. Darwin argues that these “moral sentiments” evolved as the sine qua non of social (or communal) solidarity, on which depends the survival and reproductive success of the individual members of society (or community). The tradition of dichotomous thinking in Western philosophy inclines most philosophers to dismiss Hume's ethics as a kind of irrational emotivism, despite the fact that, Callicott believes, Hume clearly provides a key role for reason in moral action and judgment. The faculty of reason, according to Hume, determines (1) relations of ideas, which are essentially logical relationships; and (2) matters of fact. Among such matters of fact, reason both traces the often complex causal chain of the consequences of various actions and discloses the proper objects of the moral sentiments. Accordingly, Leopold also traces both the causal chain of ecological consequences of such seemingly innocent actions as tilling the soil and grazing cattle and discloses a proper object of those moral sentiments — such as loyalty and patriotism — which