Locke on Substance in General

Locke’s conception of substance in general or substratum has two relatively widespread interpretations. According to one, substance in general is the bearer of properties, a pure subject, something which sustains properties but itself has no properties. I will call this interpretation traditional, because it has already been formulated by Leibniz. According to the other interpretation, substance is general is something like real essence: an underlying structure which is responsible for the fact that certain observable properties form stable, recurrent clusters. I will argue that both interpretation are partly right, and what is good in them can be reconciled. The traditional interpretation captures the purpose and signficanc of the idea of substance in general, i.e. the reason why Locke says we have this idea. The real essence view is right about the real world counterpart of the idea, i.e. what sort of entity the idea corresponds to. The paper starts with a review of the strengths and weaknesses of the rival interpretations (I, II). Then I examine which part of the traditional interpretation can be sustained in light of the problems it faces (III). Thereafter I will show that the part of the traditional interpretation which can be sustained cannot stand on its own and needs to be supplemented at one point, and the real essence view can provide what is needed. This, as it were, mixed interpretation will be supported by sketching an argument which is plausible within the context of Locke’s teachings and which explains how Locke could have arrived from the view which the traditional interpretation correctly attributes to him to the view which the real essence interpretation takes him to espouse (IV). The two problematic points in this argument will be taken up in the following two sections. (V, VI). Finally, I will provide some evidence from the Drafts for Locke’s identification of substance and essence (VII).