Isaac Newton's groundbreaking work on natural philosophy remains one of the most influential scientific works of all time. This new translation by A. Clissold brings The Principia into the modern era, making it accessible to a new generation of scientists and science enthusiasts. This work is in the "public domain in the United States of America, and possibly other nations. Within the United States, you may freely copy and distribute this work, as no entity (individual or corporate) has a copyright on the body of the work.