Modal uses of knowledge verbs in Ancient Greek

In Ancient Greek – as in several other languages – knowledge verbs may express, besides epistemic knowledge (‘know that’), also performative knowledge (‘know how to’), thus getting close to the domain of dynamic modality. This study focuses on the semantic and syntactic behaviour of the Ancient Greek knowledge verbs epístamai, oîda, gignṓskō, in order to detect the conditions enabling their modal uses (in particular with non-finite complementation patterns) and to explore the hypothesis of an ongoing grammaticalization process. With respect to the first issue, it is argued that the dynamic modal reading appears when the knowledge verb is complemented by a tense-defective infinitival complement, characterized by obligatory subject coreference (control). With respect to the second issue, the coexistence of the epistemic and the modal dynamic value is understood as a stable feature of the language, rather than as a result of achieved grammaticalization. This clearly emerges from the contrast with a functional (raising) modal verb such as dúnamai ‘can’.