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Markkula Center for Applied Ethics

Lesson Seven

The Role of Science in Environmental Ethics

Science is a powerful way of knowing that has transformed the relationship between human society and the natural world. Drawn from the Latin word for knowledge, in the broadest sense, science means a systematic way of gathering information and drawing conclusions. In a more restricted sense, science refers to information gathered using the scientific method, a systematic approach to gathering empirical (observable and measurable) data and determining facts about nature or society. A scientific approach to studying the natural or social world asks clear, specific questions, makes predictions (proposes hypotheses), tests the accuracy of those predictions, and draws conclusions based on measurable evidence. The natural sciences use the scientific method to investigate the natural world, and social scientists use it to research social issues, in other words, in human society. When conducting experiments with natural phenomena, scientists using this method can determine cause and effect relationships. The scientific method attempts to determine knowledge by eliminating, so far as possible, the potential for our own interests and desires to influence the results. This has increased the sophistication of our understanding of how the plants, animals, nutrients and energy are related in the environment.

Astonishing benefits, but not without problems

Science, technology and engineering have brought terrific benefits to society, and have made astounding wealth and material comfort possible. Yet upon closer analysis, many people have observed that these forces have had ambivalent effects. Tremendous benefits made possible by scientists and the scientific method have not been without negative impacts on the Earth, and in some cases, for the poor. The automobile has brought us convenience in transport, yet we have paved over much fertile farmland to make roads. Fossil fuels, such as oil and gas, have made possible all manner of industry and devices, yet the carbon dioxide emissions from their burning play a significant role in disrupting our atmosphere and climate. Nuclear technologies can promote health, for example, through radiation treatments for cancer. Yet these same when used for war could bring about indescribably horrific suffering. Nuclear energy produces no greenhouse gasses, which is good, but its waste products are radioactive (acutely dangerous) for 10,000 years or more. The wealthy nations of the world have generated great economic benefits through technology, but at times these technologies have extracted goods from poorer countries, and further frustrated their economic growth.

Science and the scientific method do not, by themselves, indicate what humans should do. By working to minimize bias, scientists are better able to determine knowledge of the natural world. But the "exclusion" of human values from the scientific method - which might bias the results - also means that its products are considered by most people to be amoral, in other words, neither ethical nor unethical. This has resulted in the widespread perception that scientific and technological developments should continue without considering the ethical implications of their products. The scientific method attempts to be free of bias, but the technological products of science have tremendous implications for social and environmental ethics.

The contributions of ecology

But "science" has many branches, or disciplines; it is not a single, homogenous entity. Physics, chemistry and biology all share the scientific method, but they have differences as well. The Biological sciences, and especially the discipline of ecology, play a particularly strong role in explaining humanity's relationship with the natural world. Biology was developed in the 19th Century when scientists discovered that all living organisms share characteristics. In a modified form, Charles Darwin's discovery of evolution is still a foundational principle of biology. Evolution provides a coherent and unifying explanation for why life on Earth is biologically diverse, why our planet hosts so many different kinds of species. A "species" is the basic unit of biological classification, generally defined as a group of organisms sufficiently similar that they can sexually reproduce and generate fertile offspring. For several reasons, there is no agreed upon number of species on Earth (between two and a hundred million, depending on how they are estimated and how much uncertainty is considered).

Ecology is the study of the distribution and abundance of living organisms and the interactions among organisms and between organisms and their environment. This scientific discipline addresses the challenges of researching complex data in the natural world. Over the past few decades, biology has largely conducted studies with living organisms in laboratories. This allows for very precise research, but usually at the expense of considering the broader environmental context in which organisms naturally live. The great investment in laboratory work is part of a broader trend in science: reductionism, or the study of complex phenomena by analyzing only their individual components.

Ecology takes a different approach, because it studies living organisms in dynamic systems. Thus, it tackles the big picture questions in environmental science. This ambition is admirable, but makes the gathering of consistent data very difficult. Biological research restricted to a laboratory is better able to determine cause and effect relationships, but usually disregards the broader and more complex environmental implications. Ecologists investigate the dynamic changing relationships between populations, groups of organisms, and food and energy flows, over time and in response to various stresses (such as pollution). They often research the impact of human behavior on natural communities.

The science of ecology has contributed a most important concept: the ecosystem. An ecosystem is an association of organisms and their physical environment, interconnected by the circulation of energy and nutrients. An ecosystem may be any size, from a drop of water to our entire planet. All creatures live within some kind of ecosystem and relate or influence each other - and their environment - by their behavior. The idea of an ecosystem is critical to understanding the patterns of life on earth, and points to the inescapable inter-relatedness of all life.

The extinction of species is considered an event of special ethical concern because it is an irreversible act, much like murder or execution. Each species is the result of an irreproducible process of evolution and speciation (the evolutionary process by which species arise). The passage of the U.S. Endangered Species Act in 1973 was landmark legislation that reflected environmental ethical concerns that had been expressed over the prior decades. Conservation Biology (also known as Conservation Ecology) is a special subfield interested in the preservation of life's full diversity, and the ecosystems necessary to support their conservation. It is an example of a scientific field that has an explicit ethical orientation: the conservation of biological diversity. This is an example of the ethical notion of consequence.

The special relationship of ecology and environmental ethics

Ecology plays a privileged role in environmental ethics. Aldo Leopold and Rachel Carson were two pioneering environmental ethicists with advanced training in ecology, and this profoundly influenced their moral vision of the natural world. Leopold was an ecologist, farmer, forester and conservationist who wrote explicitly about human moral duties to nature. He was the first to articulate a land ethic, or to describe moral responsibilities for land. His most important book was "A Sand County Almanac" (Leopold, 1949). In his chapter on a land ethic he claimed: "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." This appears to be the first explicit ethical statement about the importance of an ecosystem. Leopold expanded the boundaries of what was morally considerable from human society to include biological communities.

The philosophy of Deep Ecology, first named and articulated by Norwegian philosopher Arne Næss, builds on Leopold's land ethic and the science of ecology to articulate a vision for how humans should live in relationship to the Earth. Deep Ecology begins with the proposition that humans are a part of the earth. Many Deep Ecologists assert that humans have no more rights than other forms of life, and that a radical reorientation in human society is necessary to live within the limits of what the Earth's ecosystems can provide. They reject the very notion of "natural resources" because that statement assumes that elements and organisms are important only as economic commodities for humans. Deep Ecology asserts that nature, the environment, and ecosystems have intrinsic value, meaning that they are deserving of moral consideration and protection merely because they exist. They do not have value because they meet human needs, but because they are a part of the Earth.

Deep Ecology argues that a human-centered worldview, known as anthropocentrism, is at the root of our environmental crises. This line of critique links exponential human population growth and environmental degradation as being symptoms of a worldview that does not value other forms of life, and ignores the consequences of disrupting ecosystems. It proposes biocentrism, or an eco-centric approach, as the antidote, although there are several variations of these. Some propose that humans have no more rights than other forms of life, although this is easier to say than to actually live out. A more practical biocentric philosophical approach argues that the Earth's ecosystems deserve our respect and protection.

This principle of the Earth and its creatures having intrinsic value is particularly strong in Deep Ecology, but is in no way limited to this philosophical approach. Concern for threatened and endangered species is based on the principle of intrinsic value. Most species of organisms in the environment do not provide economic value, or at least we do not have clear evidence of how they provide direct benefits to humans. Restraining human activities that harm the earth, when undertaken for non-economic reasons, can be traced back to some kind ethic, whether it is beauty (an aesthetic ethic) or just because it is (intrinsic value). Many arguments for the conservation of biological diversity reach an impasse because proponents assume that other forms of life have intrinsic moral value, while their opponents do not. Finding ways to move beyond this impasse is an essential task for environmental ethics.

The idea of the ecosystem has contributed to the philosophical idea of holism, or the idea that a system has properties that can only be perceived by looking at components, their inter-relationships, and the functioning of the whole system. For example, a scientist can examine individual organisms in a laboratory setting, but they may behave differently in their natural environment. The ethical implication of holism is that entire systems have moral significance, meaning that we have duties to consider not merely individual members but the entire set of relationships and attributes of whole ecosystems. This proposition has a certain philosophical appeal, but translating it into an applied ethical practice is challenging. Few people appear capable or disposed to actually consider the well-being of ecosystems in their moral decision making. Finding an appropriate way to apply the concept of holism is on the frontier of environmental ethics. The science of ecology has made visible the inner workings of the ecological bases of holism. It is the task of environmental ethics to propose what how we should live in order to conserve the ecological processes upon which all life depends.


1. Do you believe that the diversity of life has intrinsic value? Why or why not? How do you assess the beliefs of those who disagree with you?
2. Imagine you were asked to make an argument for protecting an endangered species, but at the cost of restricting economic development. How would you combine scientific and ethical principles to do so?
3. Have you ever heard or made an ethical argument based on holism? Have you thought about the relationship between the concept of an ecosystem and an ethic of holism? How might you use these ideas in an ethical argument?

For more reading

Devall, W. and Sessions, G., 1985. Deep Ecology: Living As if Nature Mattered. Gibbs M. Smith, Inc., Salt Lake City.
Leopold, A., 1949. A Sand County Almanac. Oxford University Press, London.

Keith Warner, OFM, is the Assistant Director for Education, Center for Science, Technology, and Society at Santa Clara University and David DeCosse is the Director of Campus Ethics Programs at the Markkula Center for Applied Ethics.

May 1, 2009