The infinitive in Baltic and Balto-Slavic

Abstract This article presents a new approach to the Baltic and Balto-Slavic infinitive system. It is argued that the traditional view (which, in essence, derives the Slavic infinitive -ti from PIE loc. sg. *-tēi̯ and projects all Baltic infinitive endings back into Balto-Slavic) is for several reasons problematic. Balto-Slavic possessed just one infinitive (OCS -ti, Lith. -ti < Bl.-Sl. *-tī < PIE dat. sg. *-tei̯-ei̯, as per Hill 2016) and a supine (OCS -tъ, Lith. -tų < Bl.-Sl. *-tun < PIE acc. sg. *-tum). All other infinitive endings of Baltic (OPr. -twei, Lith. dial. -tie, Latv. refl. -tiê-s) were an exclusive creation of this branch. The reasons for the expansion of the infinitive in Baltic are also discussed.