Vegetarianism is defined here as the view that the needless killing or eating of animals is wrong. A number of environmental ethicists oppose animal liberation in general and vegetarianism in particular. Many of their arguments are motivated by a concern that the principles of animal liberation imply negative evaluations of life processes intimately associated with the natural world, particularly pain, death, and predation. Environmentalists also charge that animal liberation entails a distancing of humanity from nature in a manner that is (...) untenable and, to the extent that it is attempted, spiritually if not physically unhealthy. ;Likewise, animal liberationists attack the philosophical foundations of environmentalism. They argue that non-sentient life can have neither intrinsic value nor moral rights. Animal liberationists fear that a realm of values which is too broad--including plants, rivers, ecosystems, and any natural event--would prevent the animal liberation agenda from gaining a moral foothold. Human activities such as hunting and eating animals can easily be swallowed up in natural categories, the environmentalists' gateway to positive evaluation. ;In the midst of the ongoing dispute between vegetarianism and environmentalism, this dissertation comes to the defense of each against the other. I argue that each side in the dispute makes the philosophical mistake of clinging to a monistic axiology. I argue also that vegetarianism and environmentalism are interwoven as programs for practical change. ;Neither mainstream animal liberationism nor mainstream environmentalism has done a very good job of addressing the impact of its agenda on issues of interhuman justice. I examine radical environmentalisms which have done exactly this. Two of these left-wing environmentalisms, deep and social ecology, have failed both the animals and themselves by not addressing animal welfare directly. A third, ecofeminism, will be shown to have done the best job of articulating a coherent position which addresses all three concerns: environmentalism, vegetarianism, and social justice. ;I conclude by discussing previous visions of a humane, just, and environmentally sound society. Most lack nothing in recommendations for ways in which humans and animals might live apart. I argue that a successful program will reject that separation. (shrink)