Platforms of Palaeolithic knappers reveal complex linguistic abilities

Recent studies in cognitive neurosciences have postulated a possible link between manual praxis such as tool-making and human languages. If confirmed, such a link opens significant avenues towards the study of the evolution of natural languages. Yet, archaeologists would need the development of a rigorous methodology to formalize language appearance. We propose a ‘formal grammar of action’ to help formalizing some early aspects of lithic chaînes opératoires, and simultaneously question the link with human cognitive abilities. The approach, based on the foundations of Chomsky’s minimalist program and the grammar of action theory, focuses on the development of components and syntax suggested by some aspects of knapping during early phases and simple (Oldowan and early Acheulean) technologies. In this theoretical study, we rigorously analyse terminals and non-terminals (vocabulary), production rules and syntax (grammar) of idealized stone technologies and then provide possible productions (tools and handaxes). More specifically, issues related to platform preparation and cognitive strategies required during knapping are discussed. Formal grammars proposed here for interpreting knapping contribute to a greater systematization in classifying chaînes opératoires and in exploring complexity in lithic reduction sequences. As a central result, these grammars are theoretically able to rigorously demonstrate syntax presence and central recursion, thus helping us to study early linguistic abilities.