This volume focuses on recursion and reveals a host of new theoretical arguments, philosophical perspectives, formal representations and empirical evidence from parsing, acquisition and computer models, highlighting its central role in modern science. Noam Chomsky, whose work introduced recursion to linguistics and cognitive science and other leading researchers in the fields of philosophy, semantics, computer science and psycholinguistics in showing the profound reach of this concept into modern science. Recursion has been at the heart of generative grammar from the outset. Recent work in minimalism has put it at center-stage with a wide range of consequences across the intellectual landscape. The contributor to this volume both advance the field and provide a cross-sectional view of the place that recursion takes in modern science.