Subject clitics in English
As a counterexample to unidirectionality in grammaticalization, Newmeyer (1998:270) cites the loss of second-person singular subject clitics, e.g., in <i>hastou</i> and <i>wiltou</i>, in 16th century English (Kroch et al. 1982). These forms are a common, albeit optional, feature of Middle English. Though full <i>thou</i> forms replace <i>-tou/-tow</i> clitics in Early Modern English, second-person plural enclitics, subject proclitics, and object enclitics attest to the continued viability of clisis. This paper argues that <i>-tou/-tow</i> is a reduced form, not a clitic, its disappearance being attributable to loss of a phonological rule, not decliticization. This change predates the replacement of <i>thou</i> by <i>you</i>, the non-expression of subjects in imperatives, and the spread of <i>do</i> in questions and is sudden rather than gradual.