We applaud Heintz & Scott-Phillips's guiding metaphor of “unleashing leashed expression,” and we value the unified explanation for the emergence of not only language, but also other forms of unleashed expression, such as multimodal communication. We are more critical of the authors' discussion of the selection pressures acting towards unleashed expression, which are proposed to hinge on partner choice ecology.

This paper proposes a social account for the origin of the truth value and the emergence of the first declarative sentence. Such a proposal is based on two assumptions. The first is known as the social intelligence hypothesis: that the cognitive evolution of humans is first and foremost an adaptation to social demands. The second is the function-first approach to explaining the evolution of traits: before a prototype of a new trait develops and the adaptation process begins, something already existing (...) is used for a new purpose. Applied to the emergence of declarative sentences (statements), this suggests something already existing––natural signs (such as indexical objects)––was used for the declarative function and thereby integrated into communication. I show that index display (such as the display of hunting trophies) can imply a conceptual structure similar to that informing the syntax of sentences. The view developed in this paper is broadly consistent with the argumentative theory of Mercier and Sperber, which suggests that reasoning is less adapted to decision making than to social purposes such as winning disputes. In this paper I extend this view to the evaluation of propositions expressed in declarative sentences. According to my proposal, the first declarative sentence emerged as the negation of the (implicit) negation of an implicit statement. Thereby, I suggest that the binary structure of the truth value underlying any declarative sentence is founded on disagreements based on conflicts of interests. (shrink)

As proposed for the emergence of modern languages, we argue that modern uses of languages (pragmatics) also evolved gradually in our species under the effects of human self‐domestication, with three key aspects involved in a complex feedback loop: (a) a reduction in reactive aggression, (b) the sophistication of language structure (with emerging grammars initially facilitating the transition from physical aggression to verbal aggression); and (c) the potentiation of pragmatic principles governing conversation, including, but not limited to, turn‐taking and inferential abilities. (...) Our core hypothesis is that the reduction in reactive aggression, one of the key factors in self‐domestication processes, enabled us to fully exploit our cognitive and interactional potential as applied to linguistic exchanges, and ultimately to evolve a specific form of communication governed by persuasive reciprocity—a trait of human conversation characterized by both competition and cooperation. In turn, both early crude forms of language, well suited for verbal aggression/insult, and later more sophisticated forms of language, well suited for persuasive reciprocity, significantly contributed to the resolution and reduction of (physical) aggression, thus having a return effect on the self‐domestication processes. Supporting evidence for our proposal, as well as grounds for further testing, comes mainly from the consideration of cognitive disorders, which typically simultaneously present abnormal features of self‐domestication (including aggressive behavior) and problems with pragmatics and social functioning. While various approaches to language evolution typically reduce it to a single factor, our approach considers language evolution as a multifactorial process, with each player acting upon the other, engaging in an intense mutually reinforcing feedback loop. Moreover, we see language evolution as a gradual process, continuous with the pre‐linguistic cognitive abilities, which were engaged in a positive feedback loop with linguistic innovations, and where gene‐culture co‐evolution and cultural niche construction were the main driving forces. (shrink)

We present a new road map for research on “How the Brain Got Language” that adopts an EvoDevoSocio perspective and highlights comparative neuroprimatology – the comparative study of brain, behavior and communication in extant monkeys and great apes – as providing a key grounding for hypotheses on the last common ancestor of humans and monkeys and chimpanzees and the processes which guided the evolution LCA-m → LCA-c → protohumans → H. sapiens. Such research constrains and is constrained by analysis of (...) the subsequent, primarily cultural, evolution of H. sapiens which yielded cultures involving the rich use of language. (shrink)

We present a new road map for research on “How the Brain Got Language” that adopts an EvoDevoSocio perspective and highlights comparative neuroprimatology – the comparative study of brain, behavior and communication in extant monkeys and great apes – as providing a key grounding for hypotheses on the last common ancestor of humans and monkeys and chimpanzees and the processes which guided the evolution LCA-m → LCA-c → protohumans → H. sapiens. Such research constrains and is constrained by analysis of (...) the subsequent, primarily cultural, evolution of H. sapiens which yielded cultures involving the rich use of language. (shrink)