Controversies about optimality models and adaptationist methodologies have animated the discussions of evolutionary theory in recent years. The sociobiologists, following the lead of E. O. Wilson, have argued that if Darwinian natural selection can be reliably expected to produce the best possible type of organism - one that optimizes the value of its genetic contribution to future generations - then evolution becomes a powerfully predictive theory as well as an explanatory one. The enthusiastic claims of the sociobiologists for the predictability and applicability that the optimalist approach engenders have been met with severe criticism by Richard C. Lewontin, Stephen Jay Gould, and other biologists and philosophers of biology. These original essays take up both sides of the controversy over the role of optimality models in evolutionary biology, providing a refreshingly insightful and balanced discussion of optimality issues by an interdisciplinary group of leading philosophers of biology, biologists, psychologists, anthropologists, and an economist. They focus on the current state of adaptationist and optimalist methodology in evolutionary theory, and on the possibility of extending such methodology to the human sciences, especially those of psychology and anthropology. The contributors are John DuprÉ, Peter J. Richerson and Robert Boyd, John Beatty, Philip Kitcher, Elliott Sober, John Maynard Smith, Richard C. Lewontin, John M. Emlen, John E. R. Staddon, Eric Alden Smith, Roger N. Shepard, Leda Cosmides and John Tooby, and Jack Hirshleifer. John DuprÉ is Assistant Professor of Philosophy at Stanford University. A Bradford Book.