 Even a metaphysical non-corpuscularian such as Leibniz agreed with Boyle in practical terms. “However much I agree with the Scholastics in this general and, so to speak, metaphysical explanation of the principles of bodies,” he wrote to Arnauld in July 1686, “I am as corpuscular as one can be in the explanation of particular phenomena, and it is saying nothing to allege that they have forms or qualities” (Gerhardt 1875, 2:58, trans. Mason 1967).