 As is well known, natural philosophy in the Aristotelian traditions of the thirteenth through the sixteenth centuries involved an analysis of Aristotle’s ideas about the natural world, especially within the Christianized context of the medieval period. Philosophers studying nature were often actually studying texts—such as commentaries on Aristotle—rather than conducting experiments or engaging in observations, and they often did not employ mathematical techniques. Traditionally, natural philosophy in Aristotelian circles was not conceived of as a mathematical discipline (unlike, say, optics or astronomy); instead, it focused especially on the natures of objects and on causation. In the seventeenth century, natural philosophers like Galileo, Boyle, Descartes, and Newton began to reject not only the doctrines of the Aristotelians, but their techniques as well, developing a number of new mathematical, conceptual and experimental methods. Newton respected Descartes’s rejection of Aristotelian ideas, but argued that Cartesians did not employ enough of the mathematical techniques of Galileo, or the experimental methods of Boyle, in trying to understand nature. Of course, these developments have often been regarded as central to the Scientific Revolution. Despite the centrality of these changes during the seventeenth century, however, the scope of natural philosophy had not dramatically changed. Natural philosophers like Newton expended considerable energy trying to understand, e.g., the nature of space, time and motion, but they regarded that endeavor as a component of an overarching enterprise that also included an analysis of the divine being. Newton was a natural philosopher—unlike Descartes, he was not a founder of modern philosophy, for he never wrote a treatise of the order of the Meditations. Nonetheless, his influence on philosophy in the eighteenth century was profound, extending well beyond the bounds of philosophers studying nature, encompassing numerous figures and traditions in Britain, on the Continent, and even in the New  World.[4]  Newton’s influence has at least two salient aspects.