  Leibniz’s views on the nature of matter are subtle and layered. From  the time of his youthful conversion in the Rosental, he remained  broadly sympathetic to the explanatory project of the new mechanical  philosophy and its ambition to explain natural phenomena in terms of  matter and motion rather than in terms of a wide range of irreducible formal natures. In spite of this general sympathy, however, he was  also one of the most penetrating critics of the dominant conceptions  of matter in the mechanistic tradition. This section looks first at  Leibniz’s critiques of the two most important of those conceptions  before turning to his own positive account of the passive powers of  bodies. 