Newton was born into a reasonably humble family in Lincolnshire, England, on Christmas Day, 1642. Although his mother was the daughter of a relatively prosperous man, Newton was the first in his family to obtain any education. After finishing his studies as an undergraduate at Trinity College, Cambridge, in 1665, Newton did considerable work in mathematics, rising to become the second Lucasian Professor of Mathematics at the University of Cambridge in 1669 (the first holder of the chair was his teacher, Isaac Barrow). In the early stage of his career, the 1670s, he made important contributions to experimental optics, and during the 1680s, Newton made huge advances in natural philosophy, culminating in the publication of his magnum opus, Philosophiae naturalis principia mathematica. Newton gave his treatise this title to signify his dissatisfaction with Descartes’ Principles of Philosophy, which did not live up to the Cartesian program of using mathematics to understand and explain natural phenomena. During the 1690s, Newton befriended John Locke and had several important philosophical exchanges with various figures, including G. W. Leibniz (the German philosopher and mathematician) and Richard Bentley (a London theologian). By the turn of the new century, “Newtonianism” was a powerful intellectual force in England and was soon to become a major competitor to Cartesian metaphysics and natural philosophy on the Continent. Newton and his defenders, especially the theologian Samuel Clarke, engaged in an extended philosophical and political debate with the other great critic of – and rival to – Descartes in this period, Leibniz. This debate culminated in the Leibniz-Clarke correspondence (1715–16), perhaps the most influential philosophical exchange of the eighteenth century.

When Newton was young, he learned about the latest “modern” geometrical techniques from Van Schooten's Latin edition of Descartes’ Geometry; he read the Meditations and the Principles while he was still an undergraduate student at Trinity College; and before his public and vociferous debate with Leibniz and his followers in the early eighteenth century, he considered Descartes to be his most significant predecessor in natural philosophy. Newton devoted the bulk of a long unpublished manuscript, now known as De Gravitatione, to refuting Descartes’ understanding of space, time, and motion, along with his conception of the mind-body relation and of the divine. Newton's rejection of Cartesian metaphysics was heavily influenced by the views of the Cambridge Platonist Henry More, whom he knew personally.