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Markkula Center for Applied Ethics

Environmental Activists, Heroes, and Martyrs

Aldo Leopold

Intrinsic Environmentalism

Michael Turgeon was a 2016-2017 Environmental Ethics Fellow at the Markkula Center for Applied Ethics.

Over the last few centuries, there has been a significant power shift occurring on planet Earth; the natural world that had a firm grasp on all its inhabitants has ceded much of its power to an industrialized human race, and questions we had seldom asked are now at the forefront of our ethical discourse. Do we have a duty to protect nature, and if so, who are we protecting it for? The first question seems to have a simple answer, at least because our moral intuition seems to point most of us in the same direction: nature is beautiful, and beauty is good, and thus nature is good and we should care about it. However, the second question has incited a much more intense debate.

Up until very recently, the predominant reasoning behind conservation has been largely anthropocentric— we have a duty to protect nature, but only because doing so is beneficial for us as well. We want to preserve our beautiful National Parks, and we want our grandchildren to have clean air and drinking water, but the needs and desires of non-human species are seldom considered. In the late 1960s, historian Lynn White argued that this “instrumental” or “extrinsic value” mode of thinking was at least partially derived from Judeo-Christian values, where the Book of Genesis gives man dominion over the Earth [2]. While this idea of environmental stewardship is often still viewed as a moral imperative, its underlying philosophy for protecting the environment may be inadequate (and White himself notes it is not the only perspective possible in the Judeo-Christian tradition). However, in the mid-20th century, a new environmental movement sprung forth from the philosophies of those who saw the natural world as inherently good apart from any value it has for humanity, and one of the most important thinkers in that circle was Aldo Leopold.

For Aldo Leopold, a Midwesterner born in 1887, a sincere appreciation for the natural world stemmed from his life experience. From a very young age, Aldo spent his days immersed in the outdoors. His father taught him how to hunt and the two would frequently voyage into the woods. Their family took an annual trip to the Les Cheneaux Islands in Lake Huron. Even in his day to day life, young Aldo would spend hours documenting the birds near his house, and his dream as a student was to enroll in the new forestry program at Yale University [3]. Always a bright and dedicated student, Aldo achieved his dream and translated his degree into a career of being immersed in nature.

“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.” - Aldo Leopold, A Sand County Almanac (1949) [1]

His career with the National Forest Service in the early 1900s saw him making many inroads in the rapidly expanding field of conservation; his work towards the preservation of places like the Grand Canyon and the Gila Wilderness Area, along with the work of famous contemporaries such as President Theodore Roosevelt and naturalist John Muir, helped set a precedent for the following century of American environmentalism. His pioneering work in the outdoors set him up for pioneering work in academia, as he was eventually appointed to be the first professor of wildlife management at the University of Wisconsin at Madison3. After raising a family of naturalists and ruminating on many of his revolutionary ideas about how we should treat nature, he retired to Central Wisconsin (in an area known as Sand County) and closely examined his ideas in a context where human activity had taken a major toll on the landscape.

When his landmark book, A Sand County Almanac, was posthumously published in 1949, Aldo Leopold re-wrote many of the conventions of environmentalism. He puts forth the notion of the “land ethic,” which is a philosophy that prioritizes the right to life of all members of Earth’s biotic community, and that rather than being the master of this community, humans are simply another member [1]. Humans have a duty to respect the biological community, not because it contains precious resources for humans to use, but because it inherently deserves respect. Even in the first half of the 20th century, Leopold saw the many significant environmental issues posed by a rapidly-growing and modernizing human race and understood that many of its practices were neither sustainable nor fair to the other species also inhabiting this planet. Leopold’s concerns were prescient of the future of environmentalism in America, and his philosophy truly laid the groundwork for modern environmental ethics.  

For the sake of illustrating just how powerful Leopold’s ideas were, one particularly salient ecological notion Leopold conceived is the trophic cascade. His time hunting with his father and later hunting top predators for the Forest Service showed him that interfering with animal populations can have serious ecological consequences; wolves and other predators are essential for keeping the population of deer and other down-the-food-chain species in check, and taking them out of the ecosystem causes widespread, unpredictable changes down the line [1]. This is a vital insight to ecologists today, who have noted that the cascade caused by reintroducing wolves to Yellowstone affected the health of the park so much that even the rivers changed course [4].

In the decades following A Sand County Almanac, Aldo Leopold’s ideas helped jump start a revitalized environmental movement in America. In the 1960s and 70s, other environmentalists such as Lynn White, Rachel Carson, and Paul Ehrlich also put forth important works on how humanity has been turning a blind eye to ecological consequences of its actions, and they warned the public about the impending environmental crisis [2]. And in an age of protest, whether it be about Civil Rights or the Vietnam War, environmental concerns took hold in America. Careless treatment of the environment was no longer acceptable, and we now understand that all of our actions have ecological consequences. Today, especially as we are faced with the threat of global climate change, the ideas of Aldo Leopold and his contemporaries are just as important as ever.

Aldo Leopold’s legacy is far-reaching and essential for understanding the modern discourse on environmental ethics. While we now are much more inclined to protect the environment, the motivations for doing so are still up in the air. Leopold’s work came from an era of exponential increase in environmental consciousness in America, and his way stems from morality and the natural rights of all living things, a school of thought we now deem intrinsic environmentalism. However, extrinsic, anthropocentric environmentalism, or saving the environment for the sake of humanity, still pulls its weight in environmentalist motivation. While the best line of reasoning is still not clear, what is clear is that Aldo Leopold’s work is at the center of the debate.


  1. Leopold, Aldo, and Curt Meine. Aldo Leopold: A Sand County Almanac & Other Writings on Ecology and Conservation. New York: Library of America, 2013. Print.
  2. Brennan, Andrew. "Environmental Ethics." Stanford Encyclopedia of Philosophy. Stanford University, 03 June 2002. Web.
  3. Meine, Curt. Aldo Leopold: His Life and Work. Madison, WI: U of Wisconsin, 1988. Print.
  4. "Wolf Reintroduction Changes Ecosystem." Yellowstone Park. N.p., 11 July 2016. Web.
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