This is a new translation, with introduction, commentary, and an explanatory glossary. Sachs's translation and commentary rescue Aristotle's text from the rigid, pedantic, and misleading versions that have until now obscured his thought. Thanks to Sachs's superb guidance, the Physics comes alive as a profound dialectical inquiry whose insights into the enduring questions about nature, cause, change, time, and the 'infinite' are still pertinent today. Using such guided studies in class has been exhilarating both for myself and my students. --Leon R. Kass, The Committee on Social Thought, University of Chicago Aristotle's Physics is the only complete and coherent book we have from the ancient world in which a thinker of the first rank seeks to say something about nature as a whole. For centuries, Aristotle's inquiry into the causes and conditions of motion and rest dominated science and philosophy. To understand the intellectual assumptions of a powerful world view--and the roots of the Scientific Revolution--reading Aristotle is critical. Yet existing translations of Aristotle's Physics have made it difficult to understand either Aristotle's originality or the lasting value of his work. In this volume in the Masterworks of Discovery series, Joe Sachs provides a new plain-spoken English translation of all of Aristotle's classic treatise and accompanies it with a long interpretive introduction, a running explication of the text, and a helpful glossary. He succeeds brilliantly in fulfilling the aim of this innovative series: to give the general reader the tools to read and understand a masterwork of scientific discovery.