Leibniz's Leibniz’s Hyper-Reductionism about Extrinsic Denominations: a Further Last Word?

One of Leibniz’s most characteristic metaphysical theses is that there are no ‘purely’ extrinsic denominations (NPED). Traditional reductionist accounts of NPED interpret this thesis as the assertion that extrinsic denominations reduce to (sets of) qualitative facts about the individual substances – in the plural – to which the extrinsic denomination is attributed: only the conjunction of these facts is sufficient to extract the denomination, and hence both (sets of) facts are necessary. This article radicalizes this reductionist interpretation by arguing that, more strongly, an extrinsic denomination reduces to qualitative facts about the extrinsically denominated individual alone – in the singular. To argue for this ‘hyper-reductionist’ interpretation, the article develops a detailed analysis of two Leibnizian arguments for NPED – the argument from ‘the connection of things’, and the argument from substances’ property of conceptual completeness and the containment theory of truth underpinning it. It is proposed that, when seen from the angle of this second argument, NPED turns out to be the strong thesis expressed by hyper-reductionism. After showing this, the article further explains how hyper-reductionism can be seen to accommodate Leibniz’s conception of perception as a sui generis type of absolute property.