From comparative to causal relations: the case of siccome ‘because’ in the history of Italian.

This article investigates how adverbial causal clauses come into being by tracking the diachronic development of the lexical item siccome ‘because’ from Old to Contemporary Italian. We show that adverbial causal clauses introduced by siccome in Contemporary Italian originate from comparative-similative clauses. By describing the steps of this diachronic change, we demonstrate that in specific contexts the comparative- similative marker has paved the way for a comparison between two events entailing a causal relation. The change is formalized by adopting a free relative clause analysis (Cinque 2020a) to comparative and causal clauses.