The Communicative Mind

Why do humans but not apes acquire language?

According to a standard view (Tomasello 2008; Scott-Phillips 2014) humans alone acquire language because we possess biological adaptations for Theory of Mind ('ToM') - the ability to think about others' mental states - that great apes lack. These enable us to act with and attribute the 'Gricean' (Grice 1957) communicative intentions that are necessary for natural language development. Since great apes lack ToM, they can neither attribute communicative intentions nor acquire language.

Problematically for the standard view, the ToM needed for Gricean communication seem to develop only with the mastery of certain natural language forms - 'realis complement clause' syntax - around children's fourth birthday. If the mindreading needed for Gricean communication is itself language dependent, then it cannot contribute to an explanation of children's language acquisition. Since new empirical data (Krupenye & Kano, 2017) also shows that the ToM of great apes is similar to that of pre-verbal infants, the standard view leaves the absence of language in great apes unexplained.

To dissolve these explanatory puzzles, the Communicative Mind project will develop a new account of the relationship between ToM, language, and communication. Building on the PI's previous work, which shows that infants and apes alike can engage in socio-cognitively undemanding forms of 'minimally Gricean' communication, the project will establish that key socio-cognitive differences between humans and apes are culturally learned, not biologically inherited. They emerge because humans but not apes can use syntactically structured utterances to communicate, and because on the back of this ability generations of language-users have developed linguistic tools for theorising about mental states. Thus, it is not ToM that explains the development of language, but syntax and the cultural evolution of language that explains the development of ToM. Children learn to use these tools in ontogeny, through cultural practices of conversation and storytelling, and thereby acquire new tools for thinking about minds.

The Communicative Mind will develop new accounts of the evolution of language in phylogeny, and of the development of ToM in ontogeny. In years 1 and 2 of the project, the PI (a philosopher) will work with a developmental psychologist to conduct a series of pioneering studies to illuminate the developmental relationship between complement clause syntax mastery and the ability to represent what others know. By using, for the first time, both verbal and non-verbal paradigms to study the development of children's mastery of embedded, hierarchically structured complement clause forms, we will generate new knowledge of the cognitive mechanisms that support the development of children's mindreading and language.

In years 3 and 4 of the project, the PI will work with a linguist to shed new light on the emergence of complement clause syntax in human history. We will develop a new account of the phylogenetic emergence in humans of a cognitive architecture that allows us, but not our great ape cousins, to use syntactically structured language. Subsequently we will use comparisons of existing languages to develop an account of the cultural evolution of complement-clause like syntax in natural languages.

These subprojects will combine to give an account of the cultural origins of the ability to use language to represent others' perspectives on the world. We will show how linguistic tools for ToM can be created and learned through processes of communicative interaction, and describe the new representational tools with which they imbue speakers. By showing that uniquely human cognitive traits emerge through communication, we will demonstrate the fundamentally social foundations of human thought. Subsequently we will use our findings to develop educational tools to support children's learning.

The outcome of the Communicative Mind FLF project will be a unified account of the dependence of explicit mindreading on uniquely human forms of communication, and the most sophisticated account of the cultural foundations of human mindreading to date. This research will be published across a series of high-impact journal papers, a monograph, and a number of popular science articles written to engage the public in our work, and generate excitement at our findings.

The value of the FLF research will be the way in which it combines detailed philosophical argument and empirical research to develop a big picture of the complexity of the human mind, and supports this with new and important empirical findings from linguistics and developmental psychology. Our groundbreaking developmental paradigms will contribute new knowledge of the mechanisms that support children's socio-cognitive development. Additionally, our comparative linguistics work will generate new evidence of the cultural origins of linguistic tools for mindreading, and their emergence in human history; and our philosophical writing will contribute a unified, detailed theoretical framework within which to interpret the data we have collected. Together the findings will illuminate our understanding of what makes modern humans cognitively unique. If the central hypothesis of the project is correct, then the project will show that the socio-cognitive differences between humans and apes can - in substantial part - be traced back to a simple variable: the development of superior communicative abilities in the human lineage. In showing that uniquely human cognitive traits emerge through communication, it will shed new light on the deeply social nature of human thought.

The project is groundbreaking because it will be the first rigorous and detailed philosophical defence of the communication-dependent nature of key aspects of human social cognition; and because it will reverse the explanatory priority of currently dominant views of the relationship between communication and mindreading. Thus it will shed new light on the cultural foundations of the human mind, and open up new avenues for future research. Furthermore, the project will establish the burgeoning field of philosophy of cognitive development as an important one - with the University of Warwick as a world-leading centre for such research - and testify to the important contributions that philosophy can make to the science of the mind. Additionally the project will contribute a cross-disciplinary theoretical framework that will facilitate future collaborative interactions from ToM and language researchers across numerous disciplines within the cognitive sciences.

By providing new knowledge of the developmental relationship between mindreading and communication, the FLF project will also support the development of a range of teaching strategies. These will be developed in collaboration with educators in the later stages of the project, along with tools for evaluating and refining the use of these teaching tools in classroom scenarios. Ultimately, this feedback could be used to drive evidence based education policy-making. Finally, the project will have important implications for our understanding of the relationships between human and great ape minds. This will have important consequences for our thinking about the status of great apes as persons, and could be used to support new efforts in great ape conservation.