Cyclical change and problems of projection

In diachronic change, specifiers are reanalysed as heads and heads as higher heads. When the older specifiers and heads are renewed, a linguistic cycle emerges. Explanations provided for these cycles include structural and featural economy (e.g. van Gelderen 2004; 2011). Chomsky’s (2013, 2015) focus on labelling as unconnected to merge makes it possible to see the cycles in another way, namely as resolutions to labelling problems. The Labelling Algorithm (LA) operates after merge is complete, when a syntactic derivation is transferred to the interfaces. When a head and a phrase merge, the LA determines that the head is the label by Minimal Search. Where two phrases merge, the LA cannot find the head and one of the phrases has to either move or share features with the other. This chapter argues that, in addition to Chomsky’s resolutions to labelling paradoxes, reanalysing a phrase as a head also resolves the paradox. It also shows that the third factor principle minimal search is preferable over feature-sharing. The change from phrase to head is frequent, as eight cross-linguistically attested changes show. In addition, in the renewal stage of a cycle, adjuncts are frequently incorporated as arguments showing a preference of set-merge (feature-sharing) over pair-merge.