This book is the first to examine language universals from a cross-disciplinary perspective. It provides new insights into long standing questions such as: What exactly defines the human capacity for language? Are there universal properties of human languages and, if so, what are they? Can all language universals be explained in the same way, or do some universals require different kinds of explanations from others? It is unique in starting with the assumption that the best way to approach these and related questions is through a dialogue between a wide range of disciplines, including linguistics, cognitive neuroscience, philosophy, computer science and biology.