Abstract

The structure of the universe and of most objects in it is determined by a small number of physical constants. It can be shown that only a limited range of values for each of these constants is compatible with the existence of human life. The fact that we are able to exist--but just barely--calls for an explanation. In the last fifteen years, an "anthropic principle" has been proposed as a possible scientific explanation of the fortuitous features of our world. This type of explanation focuses on ways in which the presence of human beings guarantees that conditions in the early universe be suitable for the eventual development of intelligent life. In its strongest form, the anthropic principle is teleological: the universe is habitable precisely so that humans can evolve in it. ;Many issues surrounding the principle and its role in contemporary cosmology have been widely misunderstood by physicists and philosophers alike. My project is to clarify the nature of the principle and to criticize its value as a scientific claim. In chapters 1 and 2, I discuss the principle's historical background, and differentiate between several distinct ideas often misleadingly categorized as "anthropic." In chapter 3, after considering the principle's scientific justification, I conclude that it is neither essentially anthropic nor capable of predictive success. In chapter 4, I argue that the principle has little, if any, explanatory power, even in its teleological form. Having put fourth a number of criticisms of the principle as a scientific principle, in the final chapter I look at the possibility of construing it in a theistic context. Although the principle is not usually considered a religious principle, its resemblance to premises used in traditional theistic arguments from design suggests that it may be more defensible if thought of in a theistic context