On the co-optation of according to as an evidential in English

The use of according to + NP has rarely been the topic of any specialized research in relation to English evidentiality, although it would probably figure among the most frequent types of reportative evidentials found in written texts. One of the problems often associated with reportatives has related to the existence of the Reportative Exception (see, e.g. AnderBois 2014), referring to the fact that the speaker may not always subjectively endorse the proposition conveyed with the support of the evidential phrase. The present study reviews the history of according to + NP from Middle English onwards, after which it began to develop evidential functions, and shows how the tendency to reject the truth of the content of the proposition marked by according to + NP arose in specific contexts containing alternative information sources, comparison, or adversative clauses. It was shortly after the diachronic appearance of according to + NP in such contexts that the more periphrastic form, in accordance with + NP, began to renovate/renew the earlier, non-evidential meanings of according to + NP. The present study also attributes the development of according to + NP to a process of co-optation (e.g. Heine 2013) rather than grammaticalization.