When Isaac Newton was not yet 25 years old, he formulated calculus, hit upon the idea of gravity, and discovered that white light was made up of all the colors of the spectrum. By 1678, Newton designed a telescope to study the movement of the planets and published Principia, a milestone in the history of science, which set forth his famous laws of motion and universal gravitation. In this third volume in the acclaimed Ackroyd's Brief Lives series (following Chaucer and J.M.W. Turner), Peter Ackroyd provides an engaging portrait of Isaac Newton, illuminating what we think we know about him and describing his seminal contributions to science and mathematics.