THE TERM (Sustainability) HAS BECOME so widely used that it is in danger of meaning nothing. It has been applied to all manner of activities in an effort to give those activities the gloss of moral imperative, the cachet of environmental enlightenment. Sustainable has been used variously to mean politically feasible, economically feasible, not part of a pyramid or bubble, socially enlightened, consistent with neoconservative small-government dogma, consistent with liberal principles of justice and fairness, morally desirable, and, at its most diffuse, sensibly far-sighted.

Eric Zencey, "Theses on Sustainability" in Orion, May/June 2010.