Evolutionary Pragmatics Forum

Positive affect, or the expression of positive emotions, is ubiquitous across human cultures. Humans smile and laugh as an expression of emotion, but also as a communicative signal of friendliness, and as a support for communication. Laughter as a signal seems to be rooted in rough-and-tumble play – used to signal the nonaggressive intent in the play behaviors. Apes, however, also laugh during tickling events, both within and across species, which may indicate other pro-social communicative functions. However, ape laughter has so far been described as involuntary and unmodifiable, in contrast to much human laughter. In bottlenose dolphins, my lab has been investigating a separate potential behavioral marker of positive affect, the victory squeal. In data from bottlenose dolphin/human interactions, we argue that this vocalization and other behaviors may have been adapted to signal positive affect across species boundaries. The signal may be modified to mimic human vocalizations or co-opted from natural dolphin vocalizations, but most likely the communicative exchange is adjusted based on the culture of each facility and the individuals involved. Potential evolutionary implications and future directions will be explored.

Commitments can serve to secure mutually beneficial interaction in the face of short-term incentives to cheat. In this talk, I argue that pre-linguistic commitment among our early hominin ancestors took the form of participation in shared activities. I show how this facilitated the evolution of language. Increasingly powerful linguistic capacities allowed us to make increasingly effective commitments. As such, I highlight how commitment, communication and cooperation coevolved in our history. I suggest this coevolution is a crucial part of the explanation of modern human prosociality.

In this talk, I will provide an overview of some of my research (including methods and results from selected projects), as well as discuss future directions and ongoing work. In a nutshell, my research so far focuses on identifying the social, environmental, and cognitive pressures that shape the evolution of language in our species, using a range behavioral paradigms and computational models. My goal is to shed light on the communicative pressures and cognitive constraints that shape social interaction and language use, and to identify the cultural and environmental factors that lead to cross-linguistic variation.

I will outline a theory of social interaction, “Virtual Bargaining,” according to which people are able to jointly reason, act and communicate by finding implicit agreements about joint actions, conventions and norms of all kinds. These agreements are improvised “in the moment”, but are layered on prior agreements to produce cultural traditions. I will consider how far this viewpoint can be used as a foundation for communicative pragmatics and meaning, and the emergence of language.

Non-human great apes inform one another in ways that can seem very humanlike. Especially in the gestural domain, their behavior exhibits many similarities with human communication, meeting widely used empirical criteria for intentionality. At the same time, there remain some manifest differences, most obviously the enormous range and scope of human expression. How to account for these similarities and differences in a unified way remains a major challenge. This presentation will summarise the arguments of my recent paper with Christophe Heintz. We make a key distinction between the expression of intentions (Ladyginian) and the expression of specifically informative intentions (Gricean), and I will situate this distinction within a ‘special case of’ framework for classifying different modes of attention manipulation. The paper also argues that the attested tendencies of great ape interaction—for instance, to be dyadic rather than triadic, to be about the here-and-now rather than ‘displaced’, and to have a high degree of perceptual resemblance between form and meaning—are products of its Ladyginian but not Gricean character. I will summarise how we reinterpret video footage of great ape gesture as Ladyginian but not Gricean, and how we distinguish several varieties of meaning that are continuous with one another. We conclude that the evolutionary origins of linguistic meaning lie in gradual changes in not communication systems as such, but rather in social cognition, and specifically in what modes of attention manipulation are enabled by a species’ cognitive phenotype: first Ladyginian and in turn Gricean. The second of these shifts rendered humans, and only humans, ‘language ready’.

Scott-Phillips, T., & Heintz, C. (2023). Great ape interaction: Ladyginian but not Gricean. Proceedings of the National Academy of Sciences, 120(42), e2300243120.

In his recent book, Terrace (2019) argues that chimpanzees do not acquire language because they do not understand the meanings of signs, including words. A similar conclusion has been endorsed by Yang (2013) and Berwick and Chomsky (2019). On this sceptical conclusion, chimpanzees and bonobos can learn to manipulate word-like symbols for instrumental gains but cannot understand their meanings in the ways that humans do.  

In this talk, I argue that the sceptical view is motivated not by compelling empirical data, but by an elevated and seemingly misguided conception of what is required for knowing the meaning of a sign. I will argue that there are no compelling theoretical grounds on which to endorse the sceptical conclusion. I also propose an account of what knowing the meaning of a sign consists in, which does not presuppose any syntactic competence. I will argue that this approach supports the development of a single account of knowledge of meaning that can be applied to studies of communication in humans, primates, dogs, and other species; and I will also sketch an account of the pragmatic framework within which intentional communication in humans, great apes, and dogs takes place.

I finish by concluding that the sceptical conclusion does not support an account of why chimpanzees fail to acquire language, and that an alternative explanation is needed.

Gricean accounts characterize human communication as involving complex communicative intentions. However, this picture has proved controversial in explaining the emergence of the communicative system. As an alternative, I propose an action-based theory involving two functional components: (1) flexibly marking entities (like objects and actions) as communicative, thereby producing an open-ended range of communicative means; (2) manipulating these entities as external representations to convey detached contents, thereby enabling open-ended transmission of information. These human-specific components can parsimoniously explain a similar range of behaviors to Gricean formulations without appealing to communicative intentions.

For those interested in language evolution, nonhuman primates present a problem. They have, certainly compared with humans, a relatively small repertoire of vocalizations, yet they live in complex societies where individuals have different relationships that require communication in subtly different ways. How do they make a simple vocal repertoire “work” in a complex society? To answer this question, I consider the cognitive mechanisms that underlie primate communication – in particular, what individuals know about each other, their social relationships, and their motives and intentions. I suggest that, when language evolved from a pre-linguistic ancestor, many of its distinctive cognitive elements were already in place.

I will discuss the basics of the Theory of Affective Pragmatics I have developed over the past few years. Its core tenet is that emotional expressions qualify as speech act analogs: they describe what the world is like, make action commitments, express inner states and make demands on others. I will address some critiques the theory has received. I will then shift my focus to some experiments I have run jointly with Ursula Hess and Shlomo Hareli to shed light on the nature of the imperative dimension of emotional expressions, which turns out to be more complex than the Theory of Affective Pragmatics initially posited. I will then share some empirical work in progress which uses the reverse correlation method to understand the mental representations subjects spontaneously use to infer emotional appeals from facial displays. Finally, I discuss how the basic framework of the Theory of Affective Pragmatics can be extended in one of two new directions (still need to decide which one I will focus on): human-machine interactions and punishment.

Several theorists of language evolution agree that “language as we know it had to be preceded by something intermediate between true language and an ACS [animal communication system]” (Bickerton 2009). The hypothetical evolutionary intermediary between ACSs and human language is what these theorists have referred to as “Protolanguage”. Assuming (as I will in this paper) – contra Chomsky – that Protolanguage constitutes a conceptually and theoretically cogent construct, my aim in this paper is to begin to articulate an intermediary pragmatic conception of Protolanguage. After making certain observations concerning Protolanguage, I explain the sense in which my proposed conception of Protolanguage is pragmatic. I then explain what renders this conception intermediary. I conclude by outlining how we can conceive of a pragmatically intermediate protolanguage.

In this talk, we present a new paper in which we propose a Complexity Hierarchy of grammars that map between sound and meaning, beginning with relatively trivial one-word grammars and culminating with the grammars of modern human languages. We argue that the levels in this hierarchy are plausible and necessary stages in the evolution of the contemporary human language faculty. We further argue that these levels leave traces in contemporary language, including home sign and emerging sign languages.

This gradualist scenario has implications for the division of labor between grammar and pragmatics. The simpler grammars in the Complexity Hierarchy place a strong reliance on pragmatics for many aspects of utterance meaning, including even basic questions such as who did what to whom. As grammars move up the Complexity Hierarchy, these relatively simple interpretive factors become more systematic and less dependent on pragmatic inferences. However, pragmatic processes do not disappear. Rather, they change in character: Syntax, semantics, and the lexicon trigger highly structured pragmatic phenomena such as presuppositions and implicatures in a systematic and reliable way. In a sense, the more complex the grammar, the more opportunity for such pragmatic niches.

Pointing is widely recognised as a milestone in cognitive development. Despite its centrality and the wealth of available experimental evidence, extant theories of pointing are rife with inconsistencies. I consider the account defended by Tomasello (2008, 2019), and show that it trades on a conflation between the socio-normative and the psychological dimensions of infant communication. I argue that the way out of the fly-bottle is to think of infant communication in terms of commitment sharing, and I show that normative talk in relation to infants is not only appropriate, but also indispensable to make sense of the experimental evidence.

To be a scientific discipline (i.e. one that can test predictions), evolutionary pragmatics must be able to infer ostensive communication in non-human species. Nevertheless, to the best of our knowledge, there are still no established methodologies to do so. In this talk, we will integrate conceptual analysis with empirical data from wild birds and chimpanzees to propose that “non-distinct” signals (Ben Mocha & Pika, 2019) can be used as markers for ostensive communication in non-human species. We will conclude by discussing methodological strategies to map the taxonomic distribution of pragmatic capabilities across species.

Human communication requires exceptional behavioural plasticity, given that language use relies on highly flexible adjustments to social context, interaction partner and ecological setting. Whether nonhuman primates can adjust their communicative behaviour in response to the immediate and developmental environment has critical implications for communicative innovativeness prior to the emergence of human language. Systematically comparing the same great ape species living in the wild and in man-made, artificial habitats in captivity permits a direct test of how communicative repertoires and repair strategies respond to the differences in the socio-ecological environment. Here, I present recent findings on communicative plasticity using a comparative sample of wild and zoo-housed orangutans of two different species.

Few researchers concerned with the issue are likely to dispute that modern-day speech acts came into being through something like an evolutionary process. However, not many appear to have investigated what such a process might have looked like. After a brief overview of the basic principles of cultural evolution, I will offer suggestions as to how a cultural-evolutionary account of the genesis of modern-day speech acts might go. My focus will be a “how-possibly” account of the evolution of the current practice of assertion. Central to the analysis is the suggestion that the notion of commitment widely thought to be crucial to assertion is distinguishable into three strands which I term liability, frankness, and fidelity. That tripartition raises the question whether a precursor of assertion might be characterized by just one or two of these dimensions of commitment, and whether cultural-evolutionary pressures might have moved communicating agents from one dimension to two, and then from two to our current three. The approach also enables us to raise the question whether our current practice could devolve into one of its precursors, and what might cause it to do so. Time permitting, we’ll discuss how this approach also sheds light on whether speech-act types are conventional in any interesting sense, and look at how the approach might apply to other types of speech act such as promises and commands.

This talk will chart out pragmatic development with a focus on the experiences that allow human infants to start using language for social communication. Following a working definition of pragmatics in the context of human ontogeny, we will trace the early steps of pragmatic development, from a dyadic phase, through to intentional triadic communication and early word use before briefly sketching out later developments that support adult-like communication at the sentential, multi-sentential and non-literal levels. Evidence will be provided from the study of individual differences, from randomised controlled trials and from deaf infants growing up in families with little prior experience of deafness (and who are thus at risk of reduced access to interaction). This will provide a summary of the first two chapters from a forthcoming book: Pragmatic Development: How children learn to use language for social communication. CUP.

Since the 1980s, “folk psychology”, “theory of mind”, and “mind reading” have become buzzwords across a range of academic disciplines, including evolutionary pragmatics.  Unfortunately, use of these terms is associated with some bold assumptions linking practices, principles and capacities.  Although these assumptions are rarely considered explicitly, they tend to make discussions of the underlying phenomena inconclusive and even unproductive. In an attempt to improve this situation, we propose to start with the better-established empirical facts, consider how the assumptions might be relaxed, and thus prepare the ground for more sustainable theoretical and empirical research.

Ethologists have long been aware of the impact of context on behaviour, and so it is somewhat surprising that pragmatics has not been more widely applied to non-human great ape communication. Here, we present existing evidence on the effects of context on primate communication, and make specific recommendations for recording and extracting data on different types of context, such as behavioural, social, and environmental contexts, including how we may operationalise these. We propose that broadening our view to include the context in which signals are deployed will provide new insight into non-human communication.

Human communication has been described as a contextual social inference process: listeners use utterances and social-contextual information to make inferences about speakers’ underlying intentions. Research into great ape communication has been inspired by this view to look for the evolutionary roots of the social and cognitive processes involved in human communication. This approach has been highly productive, yet it is often compromised by a too-narrow focus on how great apes use and understand individual signals. I will present a computational framework that formalizes great ape communication as a multi-faceted social inference process. This model makes accurate qualitative and quantitative predictions about real-world communicative interactions between semi-wild-living chimpanzees. When enriched with a pragmatic reasoning process, the model can be used to explain repeatedly reported differences between humans and great apes in the interpretation of ambiguous signals (e.g. pointing gestures). Importantly, the same modeling framework can be used to study word learning in young children. In a series of studies, the model makes accurate predictions about how children integrate multiple information sources when making inferences about the meanings of novel words - both on a group as well as on an individual level. Furthermore, the model allows us to test competing theories about the development of this integration process. Taken together, our approach provides a new tool kit for studying the evolution of human communication. It illustrates some deep similarities between the ways in which humans and great apes communicate, but also specifies in what ways human communication might be unique.

In this talk I present observational and experimental data on how human (children and adults) and non-human primates (chimpanzees, bonobos and orangutans) calibrate requests for actions and for objects. I will discuss the role of prospection, entitlement and accountability in the calibration of requests and outline to what degree non-human primates share with humans cognitive abilities that allow for a flexible assessment of when, how and to whom deliver requests. I will also show where the critical differences lie. In doing so, I will show what it means to interact like a human being.

I will argue that the distinctiveness of mature human communication is due, in significant part, to our uniquely powerful capacity for practical reasoning, by which I mean our capacity to reason about what to do, form intentions, and combine them into complex plans that are sensitive to our beliefs. Particularly when informed by the fruits of mindreading, this capacity for practical reasoning explains some of the features of human communication that explain its remarkable flexibility, bandwidth, and efficiency. In particular, I will discuss (i) our capacity to design both what we say and how we say it for specific addressees, (ii) our use of specialized vocabularies of signals that differ between populations, (iii) our use of context-sensitive signals, and (iii) our ability to organize individual communicative acts into organized, extended discourses. I will discuss some hypotheses about how the human capacity for practical reasoning, and its use in communication, may have evolved.

The evolution of human language is doubtlessly linked to the evolution of communication. Moreover, communication systems do certainly not evolve as ends in themselves, but rather as tools for the exchange of information and the navigation of interaction in social scenarios. In this talk we will discuss potential selection pressures for the evolution of stable communication systems in a number of different scenarios of social interaction. We will exemplify how to define such scenarios as game-theoretic models and how to analyze communicative and social behavior under evolutionary dynamics.

Languages were not fossilized until the earliest form of writing appeared around 5,500 years ago. But our human ancestors communicated long before that. The question I will address in this talk is the following: What were the earliest communicative acts, or signals, used by the first humans? Answering this question is a challenging task, because the first humans emerged around two million years ago. By looking at the pragmatic skills of human children and our closest evolutionary relatives, the great apes, we may attempt to fill in some of the blanks. In my approach, I will consider evidence from evolutionary anthropology, archaeology, developmental psychology, gesture studies, and primatology. By drawing evidence from these different fields of research I will make a case for the most likely candidates involved in the earliest form of human communication. I will consider body posture and movement, hand gestures, facial expressions, and vocalizations.

Language and social cognition come together in communication, but their relationship has been intensely contested. I hypothesize that reference systems connect language and social cognition and enable their co-development in ontogeny and co-evolution in diachrony through a positive feedback loop, whereby the development of one skill boosts the development of the other. Reference systems comprise closed-class words that encode non-representational information, which is accessed automatically and signals intersubjectivity (i.e. the speaker’s assumptions about whether the listener shares their attention or knowledge; e.g., demonstratives: ‘here’/ ‘there’; articles: ‘a’/ ‘the’, or pronouns: ‘I’/ ‘she’). To test the positive feedback loop hypothesis, I propose to investigating two developmental pathways in social cognition: that from joint attention to spatial perspective taking, and from discourse memory to common ground management. Crucially, these two developmental pathways should be investigated across three parallel timescales: in language acquisition, in language use and in language change.

In theoretical work on conversation and social interaction, many linguists and philosophers of language have emphasized the theoretical importance of “common ground.” As generally construed, common ground concerns reciprocally dependent cognitive states that two or more agents adopt and incrementally update in course of their interactions with one another. In this talk, I will develop and defend the thesis that common ground is also of theoretical importance for understanding the social behavior of a wide variety of animals. At a broad functional level, I argue that common ground emerges among animals living in social environments which requires them to interact with the same individuals over extended periods of time and in which the adaptive value of their choices depends upon their previous interactions. As particular case studies, I focus on the formation of coalitions within semi-stable groups (as in primates and other lineages) and the formation of pair-bonds (as in many lineages of birds and among some groups of ungulates). In each case, successful coordinated action requires these animals to adopt and dynamically update reciprocal attitudes about one another and about the world more generally. At the level of proximate mechanism, I argue that common ground requires a range of first-order cognitive capacities—e.g. for social perception, memory, and behavioral control—but does not require more demanding higher-order cognitive capacities of the sort at work in Theory of Mind or second-level perspective taking. I conclude the talk by briefly considering the implications of these comparative-evolutionary claims for the study of common ground in humans’ use of language.

In our talk we will argue that several key aspects of modern uses of languages (pragmatics) might have evolved gradually in our species under the effects of human self-domestication, in essence, the presence in humans of features commonly found in domesticates, most notably a reduced reactive aggression and an increased prosocial behavior. Our take-home message will be that the reduction in reactive aggression enabled us to fully exploit our cognitive and interactional potential as applied to linguistic exchanges, and ultimately, to evolve sophisticated turn-taking, as well as complex inferential abilities. This potentiation of pragmatic principles governing conversation would have co-evolved with the sophistication of language structure (with emerging grammars initially facilitating the transition from physical aggression to verbal aggression), with three key aspects (aggression, language structure, and language use) being involved in a complex feedback loop.

According to a large corpus of contemporary research into human cognitive development, human babies discern and manipulate the contents of other minds with pointing gestures. I will critically examine the empirical bases for these extraordinary claims and present an alternative account for the evolution and development of pointing and other referential activities in animals, including humans. It seems plausible that high rates of joint attention in our species are more a consequence of language-rich environments than indices of mental representation because joint attention is widespread in the animal kingdom, apparently in the complete absence of shared symbolic systems.

Verbal theories have been put forward about how social cognition (particularly mindreading) and language may have (culturally) co-evolved, but such theories that pertain to past stages of (cultural) evolution are hard to test empirically. The same holds for evolutionary interactions between the cultural evolution of language and the interactive mechanisms that help make our conversations run smoothly, such as interactive (a.k.a. other-initiated) repair. I will present simulation results of agent-based models that demonstrate how we can use computational modelling to formalize and inform our theories regarding the cultural evolutionary interactions between (i) language and mindreading and (ii) language and interactive repair.

A striking feature of the human species is our large brain, enabling some complex skills that surpass those of other species, such as tool use, social cognition, and in particular, language. The question of how the neural networks supporting these skills evolved during phylogeny is still open, mainly due to a lack of studies directly comparing human and non-human primate brains and the related behavior. First results from a consortium, the Evolution of Brain Connectivity Project, show that in adult chimpanzees, vocal sequence flexibility exceeds that reported for old world monkeys, with implications for predictions for target regions of white-matter tracts across species. In chimpanzee ontogeny, we show that behaviors with potential for structured thought, such as call sequences and tool use, emerge after two years of age. These behavioral findings are in line with our preliminary tractography results, indicating the possible emergence of a dorsal connection to the inferior frontal lobe between 2 and 4 years of age. Similar to brain development in humans, the chimpanzee data of different age groups indicate a strengthening of the dorsal tract connecting the inferior frontal lobe with the temporal/parietal regions.

One of the most distinctive features of social interaction in our species is that we use language to coordinate our future activities, and in many cases far ahead. Non-human primates don't do this, as a consequence of which their interactions remain comparatively simple and short-range. I argue that the evolution of communication for future coordination was enabled by two developments: an increase of responsiveness during the communicative exchange and the emergence of normative behaviours in the follow-up. Responsiveness was required to coordinate future interactions, but wasn't enough for coordinating interactions beyond the immediate future, which required normativity, to boot.

A central question for language evolution research is whether non-human great apes act with and attribute communicative intent. Since they seem to be relatively poor at pointing comprehension, it has often been claimed that they do not (Tomasello 2006, 2008; Scott-Phillips 2014, 2015), and that this is why humans alone acquire language. In this talk I revisit the question of great ape pointing. I argue that great apes are better at pointing comprehension than has often been supposed, and that pointing comprehension data are better explained by the hypothesis that great apes do understand communicative intent but are limited in their pragmatic interpretation abilities. I also present a theoretical model of pragmatic inference that does not presuppose language-like abilities, and which can be used to explain inferences about communicative intent made by non-human great apes and other species.

Recent discussions of animal communication and the evolution of language have advocated a ‘pragmatics-first’ approach to the subject. Seyfarth & Cheney (2017), for example, propose that “animal communication constitutes a rich pragmatic system” and that “the ubiquity of pragmatics, … suggest[s] that, as language evolved, semantics and syntax were built upon a foundation of sophisticated pragmatic inference”. I begin by distinguishing two different notions of pragmatics advocates of the ‘pragmatics-first’ approach have implicitly relied on (cf. Bar-On and Moore, 2018). On the first, Carnapian notion, pragmatic phenomena are those that involve context-dependent determination of the content or significance of an utterance or signal. On the second, Gricean notion, pragmatic phenomena involve reliance on speakers’ communicative intentions and their decipherment by their hearers. I use the distinction, first, to evaluate a recent formal linguistic analysis of monkey calls, due to Schlenker et al. (e.g. 2014, 2016a,b), which explains the derivation of call meanings through a form of pragmatic enrichment. And, second, I use the distinction to motivate the need for an ‘intermediary pragmatics’ that, I argue, applies only to a subset of animal communicative behaviors, and would allow us to reconceive the significance of animal communication for our understanding of the evolution of language.