Newtonian scholars have long been aware of a set of draft Scholia to Propositions IV to IX of Book III of the Principia (2). These were composed in the 1690’s, as part of an unimplemented plan for a second edition of the work. Since they describe supposed anticipations of Newton’s doctrines in the thought of Graeco-Roman antiquity, they have become known as the ‘classical’ Scholia (3). The analogies and parallels drawn in them are so strained, as judged by modern standards of scholarship, that it is tempting to consider them as merely literary embellishments of a scientific work. However, the sheer bulk of the manuscripts, the number of copies and variants, their relation to Newton’s other writings, and the testimony of Newton’s associates together with their publication of some of the materials, all make it certain that he considered the arguments and conclusions of the Scholia an important part of his philosophy.