What is common knowledge? According to the dominant iterative model, a group of people commonly knows that p if and only if they each individually know that p, and they furthermore each know that they each know that p, and so on to infinity. According to the integrative model proposed in this paper, a group commonly knows that p when its members are united in a state of mind of the type whose contents must be true. Epistemic integration within a (...) group is enabled by symmetrical signalling processes such as eye contact. In conversational dyads, symmetrical processing operates on pairs of signals produced by the two sides in a familiar format: speakers generate content for joint attention in main channel communication, and addressees evaluate that content in backchannel communication. Processes of reinforcement learning shape our pairwise signalling, driving the accumulation of common knowledge, both in response to extrinsic reward for coordinated action, and in response to the intrinsic reward of curiosity. Where the iterative model caps the epistemic performance of the group at the level of its weakest member, the integrative model of common knowledge shows how groups working together can outperform their strongest member working alone. (shrink)

Spelke'sWhat babies knowdescribes the remarkably sophisticated mental lives of infants through the theoretical framework of core knowledge. To Spelke, young infants possess six independent core domains, two of which allow them to reason about the social world: the core agent and the core social being systems. Critically, Spelke argues that these core systems fail to communicate prior to 10 months, resulting in an inability to understand social goals. In this commentary, I review evidence that, contrary to Spelke's claims, young infants (...) show robust understanding of social goals and intentions, consistent with claims of an early emerging moral core. (shrink)

Human beings frequently attribute anthropomorphic features, motivations and behaviors to animals, artifacts, and natural phenomena. Historically, many interpretations of this attitude have been provided within different disciplines. What most interpretations have in common is distinguishing children’s manifestations of this attitude, which are considered “natural,” from adults’ occurrences, which must be explained by resorting to particular circumstances. In this article, I argue that anthropomorphism is not grounded in specific belief systems but rather in interaction. In interaction, a non-human entity assumes a (...) place that generally is attributed to a human interlocutor, which means that it is independent of the beliefs that people may have about the nature and features of the entities that are anthropomorphized. This perspective allows us to explain the problems that emerge if we consider anthropomorphism as a belief: (i) adults under certain circumstances may anthropomorphize entities even if they perfectly know that these entities have no mental life; (ii) according to the situation, the same entity may be anthropomorphized or treated as an object; (iii) there is no consistency among the entities that are anthropomorphized; (iv) there is individual variability in anthropomorphization, and this variability derives from affective states rather than from different degrees of knowledge about the entity that is anthropomorphized or greater or lesser naivety of the person who anthropomorphizes. From this perspective, anthropomorphism is a basic human attitude that begins in infants and persists throughout life. The difference between adults and children is not qualitative but rather a matter of complexity. (shrink)

This paper offers a review of research on demonstratives from an interdisciplinary perspective. In particular, we consider the role of demonstratives in current research on language universals, language evolution, language acquisition, multimodal communication, signed language, language and perception, language in interaction, spatial imagery, and discourse processing. Traditionally, demonstratives are analyzed as a particular class of spatial deictics. Yet, a number of recent studies have argued that space is largely irrelevant to deixis and that demonstratives are primarily used for social and (...) interactive purposes. Synthesizing findings in the literature, we conclude that demonstratives are a very special class of linguistic items that are foundational to both spatial and social aspects of language and cognition. (shrink)

Signed utterances are densely packed with pointing signs, reaching a frequency of one in six signs in spontaneous conversations (de Vos, 2012; Johnston, 2013a; Morford & MacFarlane, 2003). These pointing signs attain a wide range of functions and are formally highly diversified. Based on corpus analysis of spontaneous pointing signs in Kata Kolok, a rural signing variety of Bali, this paper argues that the full meaning potentials of pointing signs come about through the integration of a varied set of linguistic (...) and extralinguistic cues. Taking this hybrid nature of pointing phenomena into account, it is argued that pointing signs may become an intrinsic aspect of sign language grammars through two mechanisms: morphemization and syntactic integration. Although not entailed in this research, this approach could implicate that some highly systematized pointing systems of speaking communities may to a degree be grammatical as well. (shrink)

Prelinguistic cognitive reference comprehension is foundational to language acquisition and higher cognitive functions. However, its ontogenetic origins in the first year of life are currently not well understood. The current study pitted cognitivist against social interactionist views. We worked with infants monthly from 10 to 13 months of age and observed their behavioral search during a reference comprehension task. Our goal was to first establish the age at which infants begin to cognitively expect an occluded object in one of two (...) locations following a communicative pointing cue. We then tested whether infants' cognitive referential expectations would prospectively predict social interaction skills and experiences (as assessed by spontaneous infant and parent pointing) or, conversely, be predicted by social interaction skills and experiences. Results revealed a linear increase in cognitive reference comprehension, with clear above chance performance, individual stability in month‐to‐month correlations, and a synchronous correlation to referential pointing all emerging at 12 months but not earlier. Regarding developmental predictions, infants' cognitive referential expectations were not predictive of social interaction skills and experiences; on the contrary, they were predicted by social interaction skills and experiences. Findings suggest that a nonverbal cognitive understanding of reference to occluded entities is neither early emerging, hard wired, nor causal to infants' or caregivers' referential pointing. Instead, this foundational skill is predicted by earlier social interaction. Findings are consistent with the view that cognitive reference comprehension develops via a social construction process in the first year of life. (shrink)

Pointing is a cornerstone of human communication, but does it take the same form in all cultures? Manual pointing with the index finger appears to be used universally, and it is often assumed to be universally preferred over other forms. Non-manual pointing with the head and face has also been widely attested, but it is usually considered of marginal significance, both empirically and theoretically. Here, we challenge this assumed marginality. Using a novel communication task, we investigated pointing preferences in the (...) Yupno of Papua New Guinea and in U.S. undergraduates. Speakers in both groups pointed at similar rates, but form preferences differed starkly: The Yupno participants used non-manual pointing numerically more often than manual pointing, whereas the U.S. participants stuck unwaveringly to index-finger pointing. The findings raise questions about why groups differ in their pointing preferences and, more broadly, about why humans communicate in the ways they do. (shrink)

Recent theoretical work in developmental psychology suggests that humans are predisposed to align their mental states with those of other individuals. One way this manifests is in cooperative communication ; that is, intentional communication aimed at aligning individuals’ mental states with respect to events in their shared environment. This idea has received strong empirical support. The purpose of this paper is to extend this account by proposing an integrative model of the biobehavioral dynamics of cooperative communication. Our formulation is based (...) on active inference. Active inference suggests that action-perception cycles operate to minimize uncertainty and optimize an individual’s internal model of the world. We propose that humans are characterized by an evolved adaptive prior belief that their mental states are aligned with, or similar to, those of conspecifics (i.e., that ‘we are the same sort of creature, inhabiting the same sort of niche’). The use of cooperative communication emerges as the principal means to gather evidence for this belief, allowing for the development of a shared narrative that is used to disambiguate interactants’ (hidden and inferred) mental states. Thus, by using cooperative communication, individuals effectively attune to a hermeneutic niche composed, in part, of others’ mental states; and, reciprocally, attune the niche to their own ends via epistemic niche construction. This means that niche construction enables features of the niche to encode precise, reliable cues about the deontic or shared value of certain action policies (e.g., the utility of using communicative constructions to disambiguate mental states, given expectations about shared prior beliefs). In turn, the alignment of mental states (prior beliefs) enables the emergence of a novel, contextualizing scale of cultural dynamics that encompasses the actions and mental states of the ensemble of interactants and their shared environment. The dynamics of this contextualizing layer of cultural organization feedback, across scales, to constrain the variability of the prior expectations of the individuals who constitute it. Our theory additionally builds upon the active inference literature by introducing a new set of neurobiologically plausible computational hypotheses for cooperative communication. We conclude with directions for future research. (shrink)

Signed utterances are densely packed with pointing signs, reaching a frequency of one in six signs in spontaneous conversations . These pointing signs attain a wide range of functions and are formally highly diversified. Based on corpus analysis of spontaneous pointing signs in Kata Kolok, a rural signing variety of Bali, this paper argues that the full meaning potentials of pointing signs come about through the integration of a varied set of linguistic and extralinguistic cues. Taking this hybrid nature of (...) pointing phenomena into account, it is argued that pointing signs may become an intrinsic aspect of sign language grammars through two mechanisms: morphemization and syntactic integration. Although not entailed in this research, this approach could implicate that some highly systematized pointing systems of speaking communities may to a degree be grammatical as well. (shrink)

Children learn about the world from the testimony of other people, often coming to accept what they are told about a variety of unobservable and indeed counter-intuitive phenomena. However, research on children’s learning from testimony has paid limited attention to the foundations of that capacity. We ask whether those foundations can be observed in infancy. We review evidence from two areas of research: infants’ sensitivity to the emotional expressions of other people; and their capacity to understand the exchange of information (...) through non-verbal gestures and vocalization. We conclude that a grasp of the bi-directional exchange of information is present early in the second year. We discuss the implications for future research, especially across different cultural settings. (shrink)

Recognized as a simple communicative behavior, referential pointing is cognitively complex because it invites a communicator to consider an addressee's knowledge. Although we know referential pointing is affected by addressees’ physical location, it remains unclear whether and how communicators’ inferences about addressees’ mental representation of the interaction space influence sensorimotor control of referential pointing. The communicative perspective-taking task requires a communicator to point at one out of multiple referents either to instruct an addressee which one should be selected (communicative, COM) (...) or to predict which one the addressee will select (non-communicative, NCOM), based on either which referents can be seen (Level-1 perspective-taking, PT1) or how the referents were perceived (Level-2 perspective-taking, PT2) by the addressee. Communicators took longer to initiate the movements in PT2 than PT1 trials, and they held their pointing fingers for longer at the referent in COM than NCOM trials. The novel findings of this study pertain to trajectory control of the pointing movements. Increasing both communicative and perspective-taking demands led to longer pointing trajectories, with an under-additive interaction between those two experimental factors. This finding suggests that participants generate communicative behaviors that are as informative as required rather than overly exaggerated displays, by integrating communicative and perspective-taking information hierarchically during sensorimotor control. This observation has consequences for models of human communication. It implies that the format of communicative and perspective-taking knowledge needs to be commensurate with the movement dynamics controlled by the sensorimotor system. (shrink)

Together with language, music is perhaps the most distinctive behavioral trait of the human species. Different hypotheses have been proposed to explain why only humans perform music and how this ability might have evolved in our species. In this paper, we advance a new model of music evolution that builds on the self-domestication view of human evolution, according to which the human phenotype is, at least in part, the outcome of a process similar to domestication in other mammals, triggered by (...) the reduction in reactive aggression responses to environmental changes. We specifically argue that self-domestication can account for some of the cognitive changes, and particularly for the behaviors conducive to the complexification of music through a cultural mechanism. We hypothesize four stages in the evolution of music under self-domestication forces: (1) collective protomusic; (2) private, timbre-oriented music; (3) small-group, pitch-oriented music; and (4) collective, tonally organized music. This line of development encompasses the worldwide diversity of music types and genres and parallels what has been hypothesized for languages. Overall, music diversity might have emerged in a gradual fashion under the effects of the enhanced cultural niche construction as shaped by the progressive decrease in reactive (i.e., impulsive, triggered by fear or anger) aggression and the increase in proactive (i.e., premeditated, goal-directed) aggression. (shrink)

I tested the hypothesis that, in infant-mother-sibling interactions, infants with older siblings aged 11 to 24 months produce deictic gestures when they are proximal to, or engaging in joint attention with, their mothers more frequently than same-aged infants without siblings. Fifteen infant-mother dyads and 10 infant-mother-sibling triads were individually observed for 15 minutes in a playroom full of toys. Infants involved in infant-mother-sibling interactions produced more deictic gestures when they were proximal to their mothers than infants in infant-mother interactions. Further, (...) infants involved in infant-mother-sibling interactions accompanied their gestures with vocalizations at a higher rate than infants in infant-mother interactions. This result suggests that infants with older siblings monitor their mothers more carefully in interactions in which their sibling is also present, and that they produce deictic gestures in order to effectively elicit joint action with their mothers. (shrink)