"Environmental history is the study of how settlements alter ecological conditions and how those changes influence each era’s ideas about nature with respect to responsible resource use from one period to the next."

J. Siry, 2005.

"The environmental historian participates in the gulf between the
ecological ideal and historical reality, between the two cultures of
science and the humanities, and between disinterested objectivity and
the ethical obligation of advocacy."

John Opie, "Environmental History: Pitfalls and Opportunities,"
Environmental Review 7 (1983): 8-16, quotation on p. 15.

"We may be entering a new phase of history, a time when we begin to
rediscover . . . the traditional teaching that power must entail
restraint and responsibility, the ancient awareness that we are
interdependent with all of nature and that our sense of community must
take in the whole of creation."

Donald Worster, "The Vulnerable Earth," in Worster, ed., The Ends of the Earth (New York: Cambridge University Press, 1989), p. 20.

"Environmental historians . . . insist that we have got to go . . . down
to the earth itself as an agent and presence in history. Here we will
discover even more fundamental forces at work over time. And to
appreciate those forces we must now and then get out of parliamentary
chambers, out of birthing rooms and factories, get out of doors
altogether, and ramble into fields, woods, and the open air. It is time
we bought a good set of walking shoes, and we cannot avoid getting some
mud on them."

Donald Worster, "Doing Environmental History," in Worster, ed., The Ends of the Earth (New York: Cambridge University Press, 1989), p. 289.

"Environmental history was . . . born out of a moral purpose, with
strong political commitments behind it, but also became, as it matured,
a scholarly enterprise that had neither any simple, nor any single,
moral or political agenda to promote. Its principal goal became one of
deepening our understanding of how humans have been affected by their
natural environment through time and, conversely, how they have affected
that environment and with what results."

Donald Worster, The Ends of the Earth (New York: Cambridge University
Press, 1989), p. 290.