  The picture of Newton's atomism as an elaboration and improvement of mechanical atomism becomes untenable once the role of force in Newton's theorising is taken into account. There is no doubting that Newton's introduction of forces, especially the gravitational force, into his mechanics was a major scientific success borne out by observational and experimental evidence. Newton famously speculated in the Preface to the Principia (Cajori, 1958, xviii), that if all forces operative in nature, including those acting between the smallest, unobservable, particles, were known, then the whole course of nature could be encompassed within his mechanics.  However, the fulfilment of such a dream would not constitute the fruition of the mechanical philosophy because of the ontological problems posed by the concept of force.