Is it possible to preserve the element of Unknown Places in our national life? Is it practicable to do so, without undue loss in economic values? I say 'yes' to both questions. But we must act vigorously and quickly, before the remaining bits of wilderness have disappeared.
Aldo Leopold, Susan Flader, J. Baird Callicott (1991). “The river of the mother of God and other essays”, Univ of Wisconsin Pr
