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Once Descartes had adopted Copernican heliocentrism, the causal theory of motion as understood by Aristotelian-scholastic natural philosophers had to be replaced along with its cosmological model. [Cambridge 1. P. 48.] Cartesian mechanics was developed around a radical comprehension that the source of motion was the same for all bodies in the universe. This idea acted as a pillar upon which a new, mechanical philosophy was constructed. According to this philosophy, the source of all motion of material objects is direct, physical contact with other material objects. The mechanical philosophy was adopted by Leibniz, Huygens, and many other prominent scientists who worked alongside Newton, indicating that much of later 17th century science was deeply rooted in Cartesian philosophy. [Cambridge 1.[CiteRef::Disalle (2004)]]

Although Descartes included many revolutionary theories of the natural world in his mosaic, he still largely relied on classical methods of theorizing and conjectured hypotheses in order to construct scientific propositions.[Newtons philosophy[CiteRef::Janiak (2016)]] Despite the fact that in the early 17th century Galileo and Boyle had already begun to test proposed theories via experimentation, Descartes still chose to use logical deductions in an attempt to prove empirical truths, instead of attempting any empirical testing or mathematical techniques.[Newtons philosophy[CiteRef::Janiak (2016)]] Although many of Newton’s ideas were either adopted directly, or adapted from Descartes views of the natural world, the method of hypotheses is one that Newton rejected outright, and instead sought different methods for arriving at his conclusions.[Newtons philosophy[CiteRef::Janiak (2016)]]

Using these principles, Newton was able to derive the law of universal gravity in the context of his method. In the Cartesian mosaic, the centripetal force had already been defined as the agent that pulled the moon towards the Earth, keeping its orbit circular rather than linear. Newton applied rules 1 and 2 to determine that the centripedal force, and the force that compelled objects to move downwards towards the Earth, were merely two different expressions of the same thing. Newton then went on to apply the third rule, and argue that this force, which he called gravity, must be a universal property of all material objects. From here, he went on to argue for the unification of superlunary and sublunary phenomena. [Cambridge, chpt. 5 [CiteRef::Harper (2009)|pp. 183-184]]

Although not all of the ontological changes to the mosaic described in The Principia were immediately accepted, the new experimental philosophy that he described influenced contemporary scientists within the same century of it’s publication. [Newtons philosophy] Both prominent 17th century natural philosophers Christiaan Huygens and John Locke are known to have taken the experimental philosophy, if not necessarily the full content of Newton’s theories, to heart.[[Newton’s philosophyCiteRef::Janiak (2016)]]. By 1700 the acceptance of “experimental philosophy” methodological structure had overtaken that of Cartesianism in England.[Newton’s philosophy[CiteRef::Janiak (2016)]]|Criticism=Although many natural philosophers in the 17th century were convinced by Newton’s views on the the proper method of conducting science, many were not willing to abandon the Cartesian mechanical philosophy. Contemporary philosopher Leibniz in particular was concerned that the theory of gravity as a regression in natural philosophy, as Newton could not account for the source of gravity. To the Cartesians, it was more important that all motion in the universe could be given a direct cause, which was only possible under the mechanical philosophy, even if this amounted to a larger gap between theory and experimental evidence.[newtons philosophy[CiteRef::Janiak (2016)]]