No Genuine Copula in Japanese: a reanalysis of 'da' as a conceptual-locative postposition plus a one-argument existential verb

This paper proposes an alternative analysis of the Japanese so-called copula da and its non-contracted form dearu. Traditionally, da/dearu has been regarded as a copula equivalent to the English to be. However, the morphosyntactic and prosodic separability of de and aru in dearu, together with the syntactic and prosodic constituency of de and the NPs preceding it, suggest that this interpretation may be inadequate. Instead, we propose that da/dearu can be reanalysed as the conceptual-locative postposition de combined with the one-argument existential verb aru 'to exist'.

Under this analysis, A=wa B dearu 'A is B' is syntactically both an existence-asserting and a domain-specifying sentence. It consists of the ONE-ARGUMENT core structure [A=wa aru] 'A exists' and the ADJUNCT [B=de] 'in the conceptual domain of B' or, more simply, 'as B'.  Schematically, this can be represented as the conjunctive proposition EXIST(A) ⋀ IN(A, B) — distinct from the atomic BE(A, B) encoded by to be. The syntactically adjunctive B=de is nevertheless non-deletable due to its pragmatic and informational indispensability, as it functions as the focus of the sentence, whereas the syntactically obligatory kare=wa aru represents the presupposition/background.

Based on this analysis, it is possible to provide a unified account of the structure, semantics and historical development of Japanese da/dearu constructions.