Leopold, Singer, and Callicott have three different interpretations of land conservation and the moral way humans treat the environment. Leopold offers a semi-altruistic version, calling for the protection in its entirety of everything that is living, and everything that is on this earth. He calls this the biotic community. Callicott sees the interesting arguments Leopold makes, but also believes that his claim, while good in theory, has gaps in its logic for practical application. Singer takes a very different approach, viewing the land from a utilitarian perspective. He will assert that G-d has given humans the earth that they can use for whatever purposes are necessary for their survival. The perspectives of all three authors combine to lay the foundation for how an individual can perceive the environment and how policies, ethics, and practices can be shaped for future generations. In Leopold's Land Ethic, he begins by asserting that as humans, we have found at least two ethics on which we base our behaviors. First, ethics was applied at the individual level. Second, ethics has shaped the interactions between man and society. Leopold believes that there is no ethical obligation in society in general towards the environment. “There is still no ethics dealing with man's relationship with the earth and with the animals and plants that grow on it. …The extension of ethics to this third element of the human environment is, if I read the evidence correctly, an evolutionary possibility and an ecological necessity. (Leopold p. 2) Leopold calls for the earth ethic to extend beyond humans, but to include the earth. "The land ethic simply expands the boundaries of community to include soils, waters, plants and animals, or collectively: middle of paper would be the first, and Callicott says: until asserting that what it said is extreme, but not in the wrong direction to ultimately achieve healthy conservation. Singer would say that Leopold is at best an environmentalist, but probably an extremist who calls for the total restructuring of human life to protect an unequal cohabitant. Singer would not necessarily characterize Callicott as an extremist, but would likely characterize him as a conservationist with an emphasis on the environment over human populations. The three authors have divergent views on conservation and how much emphasis should be placed on how people interact with the environment. Some are more extremist -- Leopold -- and others are clearly utilitarian -- Singer -- but all three articulate an idea of ​​why the environment should be regulated the way they believe it should be, and the moral and ethical reasons to do it..