Deep Ecology is a perspective in environmental philosophy based in the belief that humans must radically change their relationship to nature from one that values it solely for its usefulness to human beings to one that recognizes that nature has an inherent value. It promotes the inherent worth of all living beings regardless of their instrumental utility to human needs. Deep Ecology is not a scientific discipline rather an eco-philosophy derived from intuitive ethical principles.
It was Norwegian philosopher Arne Næss who first coined the term deep ecology. An important intellectual and inspirational figure within the environmental movement of the late twentieth century, Næss asserted that while western environmental groups of the early post-war period had raised public awareness of the environmental issues of the time, they had largely failed to have insight into and address what he argued were the underlying cultural and philosophical background to these problems.
He distinguished between what he called deep and shallow ecological thinking. Deep ecology rejects anthropocentrism in favour of ecocentrism or biocentrism. Shallow Ecology asserts that nature is only valuable insofar as it serves human interests.
In 1984, Næss and his colleague George Sessions outlined their eight basic principles of Deep ecology:
1. Inherent value
The well-being and flourishing of human and nonhuman Life on Earth have value in themselves (synonyms: intrinsic value, inherent value). These values are independent of the usefulness of the nonhuman world for human purposes.
Richness and diversity of life forms contribute to the realization of these values and are also values in themselves.
3. Vital Needs
Humans have no right to reduce this richness and diversity except to satisfy vital needs.
The flourishing of human life and cultures is compatible with a substantial decrease of the human population. The flourishing of nonhuman life requires such a decrease.
5. Human Interference
The present human interference with the nonhuman world is excessive, and the situation is rapidly worsening.
6. Policy Change
Policies must therefore be changed. These policies affect basic economic, technological, and ideological structures. The resulting state of affairs will be deeply different from the present.
7. Quality of Life
The ideological change is mainly that of appreciating life quality (dwelling in situations of inherent value) rather than adhering to an increasingly higher standard of living. There will be a profound awareness of the difference between big and great.
8. Obligation of Action
Those who subscribe to the foregoing points have an obligation directly or indirectly to try to implement the necessary changes.
Although quite a heavy read, I strongly recommend Ecology of Wisdom: Writings by Arne Næss for those interested in the concept. It's an absolutely marvelous book.