Abstract
This article surveys philosophical and scientific issues arising from questions about animal consciousness. These questions include: which animals have consciousness and what (if anything) that consciousness might be like. Just what sort(s) of science can bear on these questions is a live issue, but investigations of the behavior and neurophysiology of a wide taxonomic range of animals, as well as the phylogenetic relationships among taxa are relevant. Such questions are also deeply philosophical, with epistemological, metaphysical, and phenomenological dimensions. Progress will ultimately require interdisciplinary work by philosophers willing to engage with the empirical details of animal biology, as well as scientists who are sensitive to the philosophical complexities of the issue. The article discusses motivations for studying animal consciousness, and the common framing of such issues by analogy to the human case. Various concepts of consciousness, their historical background, and the related epistemological and metaphysical issues are described. Theories about the structure and function of consciousness are identified and assessed in the context of ideas about the evolution and distribution of consciousness, and comparative approaches to specific cognitive capacities that have often been taken to indicate that humans are not the only conscious animals.