  The emphasis on relation similarly undermines any attempt to reduce opposed or distinguished terms to some element common to both. In mid career Nishida used the language of dialectics to describe relations, while insisting that the opposed terms were not sublated into a higher unity. Later he used expressions like “the self-identity of absolute contradictories” to describe the way in which opposed terms are held together, the many and the one for example. His notion of an “inverse correlation” also reflects this method. Nishida’s emphasis on relation modifies his notion of self-reflective structures to make it clear that they maintain difference within a whole and are not simply self-replicating or recursive. This is noticeable in his last essay, for example, when he describes individual selves as focal points where world reflects itself in itself (NKZ XI, 378). His rejection of a positive foundation or substratum, and his insistence on irreducible but inseparable terms in relation, explain why the holistic tendency evident in his methodology does not devolve into a simple monism, and why many commentators refer to his philosophy as non-dualist instead.