The development of conditional /should/ in English

This paper proposes an account for the development of English “conditional” /should/. It is shown by means of a diachronic corpus study that although /should/ already had the conditional meaning in Middle and Early Modern English, /should/-conditionals show an increasing formal tense mismatch between protasis and apodosis over time. The proposed account of the syntax of conditional /should/ combines Haegeman’s (2010) analysis of conditional clauses with Kempchinsky’s (2009) analysis of subjunctives. The diachronic development of conditional /should/ is accounted for in terms of Roberts and Roussou’s (2003) theory of grammaticalization as upwards reanalysis, combined with a more fine-grained syntactic structure (Cinque 1999). It is argued that should shows signs of developing into a conditional marker