Impersonal passives
Résumé
Impersonal passives are passives of intransitive verbs. Applying passivisation to an intransitive verb results in a derived verb-form with no referential argument; the surface subject of the construction is then either absent or realised by an expletive subject. Consequently, the analysis of impersonal passives inherits the complexities of at least three related domains: (i) the cross-linguistic definition of passives in general, (ii) the analysis of subjectless sentences and (iii) the syntax of sentences with
expletive subjects.
The first section reviews the most influential characterisations of passives in the literature in terms of subject demotion and object promotion. The analyses of impersonal passives in the literature will be presented against this general backdrop.
The second section presents evidence that subject demotion does not yield a uniform class of passives based on the literature on Romance, Celtic, Slavic and Germanic. In particular, constructions that suppress the logical subject differ in whether they yield a syntactically transitive or intransitive output when applied to a transitive verb. Based on this observation, it has been argued that constructions that suppress the subject but do not de-transitivise the underlying verb should not be analysed as passives; instead these constructions should be treated as impersonal verb forms, more similar to transitive sentences with an overt impersonal subject such as Engl. one, French on, Germanic man/men than to passives. Arguably, this distinction between valency reducing passives and valency-preserving impersonals is preserved when the relevant constructions are applied to intransitive verbs.
The final section examines the question what role overt expletives play in the syntax of impersonal passives. The literature on expletives constructions in Germanic and particularly in Scandinavian provides a wealth of data that will be used to place the overt expletive subject found with impersonal passives in the context of expletive constructions more generally.