On grounding superadded properties in Locke

ABSTRACT

Scholars have employed three interpretive strategies to explain how Locke understands the metaphysical relationship between a superadded property and the material body to which it is affixed. The first is the mechanist strategy advanced by Michael Ayers and Edwin McCann. It argues that the mechanical affections of a given body are causally responsible for the operation of superadded powers. The second is the extrinsic strategy found in Mathew Stuart. It argues that Locke, who rejects mechanism, does not intend to ground superadded properties in the mechanical affections of material bodies. The third is the essentialist strategy developed by Lisa Downing. It argues that Locke, who does not adhere to mechanism, nevertheless intends to ground superadded properties in the real constitutions of their bearers. However, according to Downing, what grounds superadded properties are the nonmechanical affections of material bodies. My aim in this paper is to expand and strengthen the case for the extrinsic reading. I argue that what is recommended by Locke's writings on this topic is a thoroughly extrinsic interpretation according to which superaddition pertains exclusively to those properties for which no possible arrangement of mechanical or nonmechanical affections is causally sufficient.