The cognitive foundations of ostensive-inferential communication: Insights from the study of non-human primates’ communication

Human language has been widely conceived as a unique trait in the animal kingdom. While a long tradition has tied this uniqueness to language compositional structure stressing code-like features (e.g., Berwick and Chomsky, 2016), the pragmatic turn has emphasized the underdetermined nature of communicative acts along with the cognitive processes required to interpret them (e.g., Scott-Phillips, 2015a, 2015b). The most influential pragmatic model of human communication is the ostensive-inferential account proposed by Sperber and Wilson (1986) with Relevance Theory (RT). RT is based on the idea that communication involves the expression and recognition of intentions, two intertwined abilities enabled by the cognitive capacity of entertaining representations about others’ mental states. Within such a characterization of human language, exploring its possible uniqueness means analyzing the nature and foundation of the defining aspects of ostensive-inferential communication. Comparative approaches to the study of communication provide a lens through which analyzing these aspects. Over the last decades, the evolutionary study of non-human communication has made considerable progress, integrating concepts and findings coming from the literature on human language and shifting from a behavioural perspective to a more cognitive conception. The most promising case from this point of view is that of non-human apes, who can use signals in a very flexible way by exploiting a set of socio-cognitive abilities. From the pioneering work by Woodruff and Premack (1979), who first introduced the concept of intentional communication in primates, several investigations have tried to place the ostensive-inferential model of communication into the broader context of theoretical accounts of the evolution of primate communication. In this regard, recent evidence opened new horizons in the research on language evolution, suggesting evolutionary shared abilities to read others’ minds. This chapter reviews this evidence, with the aim of identifying possible phylogenetic precursors of the distinctive components of human language and, thus, providing theoretical and empirical considerations in favour of a continuity between animal and human cognition and communication.