  The grounds for Leibniz’s negative reaction to Newton’s conception of force, and specifically Newton’s apparent postulation of a universal force of gravitation, are various and complex. One especially important  theme, however, indicated in the passage above, concerns what  conception of force should be allowed to operate in the study of  physics. On the negative side, Leibniz thought that by postulating  what he understood to be an irreducible force holding between bodies  and acting at a distance, Newton had abandoned the intelligible  explanations of the mechanical philosophy, and returned to  uninformative scholastic accounts that rested content with the  postulation of primitive powers. On the positive side, Leibniz  thought that by treating forces as inherent powers of bodies tied  inextricably to their ability to move and be moved, his own  conception of force could preserve the intelligibility that was the  great hallmark of mechanism, while nonetheless improving upon the  work of those such as Huygens, Descartes and Galileo. For, by  Leibniz’s lights, the active and passive forces he postulates not  only render physics itself more accurate and consonant with reason  but at the same time set the stage for its intelligible grounding in  his own deeper metaphysics. In this way, Leibniz’s understanding of  dynamics becomes inextricably bound up with his more thoroughly  metaphysical views to which we must now briefly turn. 