This page occasionally gets out of date. For a more up-to-date record of my work, see my PhilPapers page. Additionally you can download (almost) everything from my ResearchGate page (and request everything you cannot download).


Full Papers

Abstract: In this paper I attempt to reconcile two claims recently defended by Mitch Green. The first is that illocutionary force is part of speaker meaning (Green 2018). The second is that illocutionary force is a product of cultural evolution (Green 2017). Consistent with the second claim, I argue that some utterances – particularly those produced by infants and great apes – are produced with communicative intent, but without illocutionary force. These utterances lack the normative properties constitutive of force because their utterers have no grasp of the norms that operate on developed speech. If there can be utterances produced with communicative intent that lack force, we must consider how exactly force is a part of speaker meaning. In response I argue that force is an inessential and acquired part of speaker meaning. As a result we need a conception of communicative intent more basic than illocutionary intent. I spell this out in terms of a ‘perlocutionary’ intention.


Abstract: Humans alone acquire language. According to one influential school of thought, we do this because we possess a uniquely human ability to act with and attribute “Gricean” communicative intentions. A challenge for this view is that attributing communicative intent seems to require cognitive abilities that infant language learners lack. After considering a range of responses to this challenge, I argue that infant language development can be explained, because Gricean communication is cognitively less demanding than many suppose. However, a consequence of this is that abilities for Gricean communication are unlikely to be uniquely human.


Abstract: In the current study, 24- to 27-month-old children (N = 37) used pointing gestures in a cooperative object choice task with either peer or adult partners. When indicating the location of a hidden toy, children pointed equally accurately for adult and peer partners but more often for adult partners. When choosing from one of three hiding places, children used adults’ pointing to find a hidden toy significantly more often than they used peers’. In interaction with peers, children’s choice behavior was at chance level. These results suggest that toddlers ascribe informative value to adults’ but not peers’ pointing gestures, and highlight the role of children’s social expectations in their communicative development.


Abstract: The previous studies have shown that human infants and domestic dogs follow the gaze of a human agent only when the agent has addressed them ostensively—e.g., by making eye contact, or calling their name. This evidence is interpreted as showing that they expect ostensive signals to precede referential information. The present study tested chimpanzees, one of the closest relatives to humans, in a series of eye-tracking experiments using an experimental design adapted from these previous studies. In the ostension conditions, a human actor made eye contact, called the participant’s name, and then looked at one of two objects. In the control conditions, a salient cue, which differed in each experiment (a colorful object, the actor’s nodding, or an eating action), attracted participants’ attention to the actor’s face, and then the actor looked at the object. Overall, chimpanzees followed the actor’s gaze to the cued object in both ostension and control conditions, and the ostensive signals did not enhance gaze following more than the control attention-getters. However, the ostensive signals enhanced subsequent attention to both target and distractor objects (but not to the actor’s face) more strongly than the control attention-getters—especially in the chimpanzees who had a close relationship with human caregivers. We interpret this as showing that chimpanzees have a simple form of communicative expectations on the basis of ostensive signals, but unlike human infants and dogs, they do not subsequently use the experimenter’s gaze to infer the intended referent. These results may reflect a limitation of non-domesticated species for interpreting humans’ ostensive signals in inter-species communication.


Abstract: In this paper, we distinguish between a number of different phenomena that have been called imitation, and identify one form – a high fidelity mechanism for social learning – considered to be crucial for the development of language. Subsequently, we consider a common claim in the language evolution literature, which is that prior to the emergence of vocal language our ancestors communicated using a sophisticated gestural protolanguage (the ‘gesture-first view’), the learning of some parts of which required manual imitation. Drawing upon evidence from recent work in neuroscience, primatology, and archaeology, we argue that while gestural communication undoubtedly played a crucial role in language evolution, there are only weak grounds for thinking that manual imitation did.


Abstract: It is sometimes claimed that Gricean communication is necessarily a form of cooperative or ‘joint’ action. A consequence of this Cooperative Communication View is that Gricean communication could not itself contribute to an explanation of the possibility of joint action. I argue that Gricean communication is not necessarily a form of joint action – even though it is often a form of joint action. This is because communicative success does not always require intentional action on the part of a hearer. Since the Cooperative Communication View entails that communication is possible only when both speaker and hearer engage in intentional action, the Cooperative Communication View is false. Rejecting it has attractive consequences for our theorising about human cognitive development, since it opens up the possibility of appealing to communicative interaction to explain the emergence of joint action in phylogeny.


Abstract: According to the socio-cognitive revolution (SCR) hypothesis, humans but not other great apes acquire language because only we possess the socio-cognitive abilities required for Gricean communication, which is a pre-requisite of language development. On this view, language emerged only following a socio- cognitive revolution in the hominin lineage that took place after the split of the Pan- Homo clade. In this paper, I argue that the SCR hypothesis is wrong. The driving forces in language evolution were not sweeping biologically driven changes to hominin social cognition. Our LCA with non-human great apes was likely already a Gricean communicator, and what came with evolution was not a raft of new socio- cognitive abilities, but subtle tweaks to existing ones. It was these tweaks, operating in conjunction with more dramatic ecological changes and a significant increase in general processing power, that set our ancestors on the road to language.


Abstract: A prevailing view is that while human communication has an ‘ostensive- inferential’ or ‘Gricean’ intentional structure, animal communication does not. This would make the psychological states that support human and animal forms of communication fundamentally different. Against this view, I argue that there are grounds to expect ostensive communication in non-human clades. This is because it is sufficient for ostensive communication that one intentionally addresses one’s utterance to one’s intended interlocutor—something that is both a functional pre-requisite of successful communication and cognitively undemanding. Furthermore, while ostension is an important feature of intentional communication, the inferences required in Gricean communication may be minimal: ostension and inference may come apart. The grounds for holding that animal communication could not be Gricean are therefore weak. I finish by defending the idea that a ‘minimally Gricean’ model of communication is a valuable tool for characterizing the communicative interactions of many animal species.


Abstract: Language’s intentional nature has been highlighted as a crucial feature distinguishing it from other communication systems. Specifically, language is often thought to depend on highly structured intentional action and mutual mindreading by a communicator and recipient. Whilst similar abilities in animals can shed light on the evolution of intentionality, they remain challenging to detect unambiguously. We revisit animal intentional communication and suggest that progress in identifying analogous capacities has been complicated by (i) the assumption that intentional (that is, voluntary) production of communicative acts requires mental-state attribution, and (ii) variation in approaches investigating communication across sensory modalities. To move forward, we argue that a framework fusing research across modalities and species is required. We structure intentional communication into a series of requirements, each of which can be operationalised, investigated empirically, and must be met for purposive, intentionally communicative acts to be demonstrated. Our unified approach helps elucidate the distribution of animal intentional communication and subsequently serves to clarify what is meant by attributions of intentional communication in animals and humans.


Abstract: On standard readings of Grice, Gricean communication requires (a) possession of a concept of belief, (b) the ability to make complex inferences about others’ goal-directed behaviour, and (c) the ability to entertain fourth order meta-representations. To the extent that these abilities are pre-requisites of Gricean communication they are inconsistent with the view that Gricean communication could play a role in cognitive development. In this paper, I argue that none of abilities (a)-(c) are necessary for communication with a Gricean intentional structure. As a result, Gricean communicative abilities may indeed play a role in cognitive development – in particular, by enabling language development. This conclusion has important implications for our theorising about human evolution.


Abstract: It is sometimes argued that while human gestures are produced ostensively and intentionally, great ape gestures are produced only intentionally. If true, this would make the psychological mechanisms underlying the different species’ communication fundamentally different, and ascriptions of meaning to chimpanzee gestures would be inappropriate. While the existence of different underlying mechanisms cannot be ruled out, in fact claims about difference are driven less by empirical data than by contested assumptions about the nature of ostensive communication. On some accounts, there are no reasons to doubt that great ape gestural communication is ostensive. If these accounts are correct, attributions of meaning to chimpanzee gestures would be justified.


Abstract: Orang-utans played a communication game in two studies testing their ability to produce and comprehend requestive pointing. While the ‘communicator’ could see but not obtain hidden food, the ‘donor’ could release the food to the communicator, but could not see its location for herself. They could coordinate successfully if the communicator pointed to the food, and if the donor comprehended his communicative goal and responded pro-socially. In Study 1, one orang-utan pointed regularly and accurately for peers. However, they responded only rarely. In Study 2, a human experimenter played the communicator’s role in three conditions, testing the apes’ comprehension of points of different heights and different degrees of ostension. There was no effect of condition. However, across conditions one donor performed well individually, and as a group orang-utans’ comprehension performance tended towards significance. We explain this on the grounds that comprehension required inferences that they found difficult – but not impossible. The finding has valuable implications for our thinking about the development of pointing in phylogeny.


Abstract: Infants can see someone pointing to one of two buckets and infer that the toy they are seeking is hidden inside. Great apes do not succeed in this task, but, surprisingly, domestic dogs do. However, whether children and dogs understand these communicative acts in the same way is not yet known. To test this possibility, an experimenter did not point, look, or extend any part of her body towards either bucket, but instead lifted and shook one via a centrally pulled rope. She did this either intentionally or accidentally, and did or did not address her act to the subject using ostensive cues. Young 2-year-old children but not dogs understood the experimenter’s act in intentional conditions. While ostensive pulling of the rope made no difference to children’s success, it actually hindered dogs’ performance. We conclude that while human children may be capable of inferring communicative intent from a wide variety actions, so long as these actions are performed intentionally, dogs are likely to be less flexible in this respect. Their understanding of communicative intention may be more dependent upon bodily markers of communicative intent, including gaze, orientation, extended limbs, and vocalisations.  This may be because humans have come under selective pressure to develop skills for communicating with absent interlocutors – where bodily co-presence is not possible.


Abstract: In the past 20 years or so, the psychological research on imitation has flourished. However, our working definition of imitation has not adequately adapted in order to reflect this research. The closest that we’ve come to a revamped conception of imitation comes from the work of Michael Tomasello. Despite its numerous virtues, Tomasello’s definition is in need of at least two significant amendments, if it is to reflect the current state of knowledge. Accordingly, it is our goal in this paper to reformulate Tomasello’s definition of imitation in order to account for both the latest empirical findings and the conceptual considerations that follow from them. Specifically, we argue that a satisfactory definition of imitation ought to be formulated as follows: imitation is the reproduction of an observed behaviour where the agent imitating (1) recognizes the behaviour of the demonstrator as goal-directed and (2) has some particular interest in or concern for replicating the precise technique performed by the author of the observed action.


Abstract: There is increasing evidence that some behavioural differences between groups of chimpanzees can be attributed neither to genetic nor to ecological variation. Such differences are likely to be maintained by social learning. While humans teach their offspring, and acquire cultural traits through imitative learning, there is little evidence of such behaviours in chimpanzees. However, by appealing only to incremental changes in motivation, attention and attention-soliciting behaviour, and without expensive changes in cognition, we can hypothesise the possible emergence of imitation and pedagogy in evolutionary history.


Abstract: Michael Tomasello and colleagues have offered various arguments to explain why apes find the comprehension of pointing difficult, despite gesturing for one another and pointing for humans. They have argued that: (i) apes fail to understand communicative intentions; (ii) they fail to understand informative, cooperative communication, and (iii) they fail to track the common ground that pointing comprehension requires. In the course of a review of the literature on apes’ production and comprehension of pointing, I reject (i) and (ii), and offer a qualified defence of (iii). Drawing on work on expressive communication, I sketch an account of a mechanism by which ape gestural communication may proceed: the showing of expressive and naturally meaningful embodied behaviours. Such gestures are easily interpretable because they present rich evidence for a communicator’s message. By contrast, pointing typically provides poor evidence for a speaker’s message, which must therefore be inferred from considerations in the common ground of the pointer and her audience. This makes pointing comprehension comparatively difficult.


Abstract: The communicative interactions of very young children almost always involve language (based on conventions), gesture (based on bodily deixis or iconicity) and directed gaze. In this study, ninety-six children (3;0 years) were asked to determine the location of a hidden toy by understanding a communicative act that contained none of these familiar means. A light-and-sound mechanism placed behind the hiding place and illuminated by a centrally placed switch was used to indicate the location of the toy. After a communicative training session, an experimenter pressed the switch either deliberately or accidentally, and with or without ostension (in the form of eye contact and child-directed speech). In no condition did she orient towards the hiding place. When the switch was pressed intentionally, children used the light-and-sound cue to find the toy – and tended to do so even in the absence of ostensive eye contact. When the experimenter pressed the switch accidentally, children searched randomly – demonstrating that they were tracking her communicative intent, and not merely choosing on the basis of salience. The absence of an effect of ostension contradicts research that ostension helps children to interpret the communicative intentions underlying unfamiliar signs. We explain this by concluding that while it may play a role in establishing a communicative interaction, it is not necessary for sustaining one; and that even with a highly novel communicative act – involving none of the means of communication on which children typically rely – three-year-olds can comprehend the communicative intentions behind an intentionally produced act.


Abstract: To the extent that language is conventional, non-verbal individuals, including human infants, must participate in conventions in order to learn to use even simple utterances of words. This raises the question of which varieties of learning could make this possible. In this paper I defend Tomasello’s (1999, 2008) claim that knowledge of linguistic conventions could be learned through imitation. This is possible because Lewisian accounts of convention have overstated what one must know to participate in conventions; and because the required knowledge could be learned imitatively. The imitation claim that I defend is consistent with what we know about both the proliferation of conventional behaviours in human children, who are skilful imitators, and the comparative absence of such behaviours in non-human great apes, who are poor at imitative learning.


Chapters in Edited Volumes


Abstract: Researchers have converged on the idea that a pragmatic understanding of communication can shed important light on the evolution of language. Accordingly, animal communication scientists have been keen to adopt insights from pragmatics research. Some authors couple their appeal to pragmatic aspects of communication with the claim that there are fundamental asymmetries between signalers and receivers in non- human animals. For example, in the case of primate vocal calls, signalers are said to produce signals unintentionally and mindlessly, whereas receivers are thought to engage in contextual interpretation to derive the significance of signals. We argue that claims about signaler-receiver asymmetries are often confused. This is partly because their authors conflate two conceptions of pragmatics, which generate different accounts of the explanatory target for accounts of the evolution of language. Here we distinguish these conceptions, in order to help specify more precisely the proper explanatory target for language evolution research.


Abstract: Some primatologists and philosophers argue that certain chimpanzee social behaviors may be normative. That is, they argue that chimpanzees sometimes act according to a conception of how one ought to behave. Since normative behavior is central to human sociality, this claim – if true – would have important conclusions for our theorizing about the evolution of humans forms of life. We argue, though, that the conclusion is unsupported by the evidence. There are currently no compelling grounds to think chimpanzee social behavior normative.


Abstract: The goals of this chapter are threefold. First, I argue that teaching has played an essential role in the survival and expansion of the human race. Second, I sketch an account of the nature of teaching. Third, I defend an account of the cognitive pre-requisites of teaching that does not presuppose sophisticated individual abilities or social mechanisms; and so is consistent with the possibility that teaching emerged early in hominin phylogeny.

Keywords: pedagogy, ontogeny, phylogeny, social learning, Natural Pedagogy


Summary: Paul Grice’s account of the nature of intentional communication has often been supposed to be cognitively too complex to work as an account of the communicative interactions of pre-verbal children. This chapter is a (fairly uncritical) review of a number of responses to this challenge that others have developed. I discuss work on Relevance Theory (by Sperber and Wilson), Pedagogy Theory (by Gergely and Csibra), and Expressive Communication (by Green and Bar-On). I also discuss my own response to the challenge of Gricean communication.


Shorter Papers and Commentaries


  • Moore, R. (2017e). There is a moral argument for keeping great apes in zoos. Aeon.






Abstract: In a recent paper, Mikhalevich argues that comparative psychologists should abandon the ‘natural null’ (Hn) model of null hypothesis testing, in favour of a ‘contextual null’ (Hc) model, which incorporates more specific information about different species’ phylogenetic relatedness, and previous empirical research. While we are sympathetic to her proposal, we argue that existing statistical tools and comparative methods are already well equipped to cope with the asymmetry bias to which Mikhalevich thinks current comparative methods are vulnerable. Furthermore, without modification – to embrace a weaker interpretation of the nature of Type II errors – Mikhalevich’s own solution may lead to distorted interpretations of empirical data.


Book Reviews

Summary:  While the Berwick and Chomsky book is good, I was too generous in the review. It’s horribly edited and very hard work in places. The Chater and Christiansen book is much easier to follow and makes some very innovative and valuable claims about the cultural evolution of natural language. However it treats the B&C claim as being about natural language (it isn’t) and attacks a version of Chomskian thinking that Chomsky would no longer defend. It’s not clear that it doesn’t also smuggle in a Chomskian reliance on hierarchical organisation. Despite the oppositional rhetoric, these books actually agree about a great deal (and far more than the authors suppose).


Summary: This book does a very good job of synthesising interdisciplinary work on language evolution. It would make an excellent introduction to the subject. However, the central argument is both theoretically dubious and empirically unsupported.


Summary: This is a first rate piece of popular science. Highly recommended.


Summary: I liked this book a lot. You should read it.


Summary: Interesting but flawed. Give it a miss.


Unpublished PhD Thesis

Summary: At around 14 or 15 months of age, human infants start to use words in their communicative interactions with others, and to respond appropriately to others’ uses of words. Soon they can use language to issue requests, to make observations, and to give orders, and to understand (or at least respond appropriately to) others’ uses of language to do the same. The central question of my thesis is: what are the cognitive abilities that one would need to attribute to infants to explain this? My answer includes a very critical discussion of Daniel Dennett’s account of infant language acquisition, described in Kinds of Minds, a chapter on Paul Bloom’s account of the role of referential intent in word-learning, and several chapters (subsequently developed in newer papers) on the roles of Gricean intentions, imitation, and Lewisian conventions in the acquisition of language.