Before claiming major differences between the communication systems of humans and other species, it is necessary to (1) overcome methodological limitations in the comparative study of communicative intentions; (2) account for mechanisms other than epistemic vigilance that may also sustain complex forms of communication; and (3) better differentiate between motivational and cognitive factors potentially affecting the emergence of open-ended communication.

To fully embrace situations of radical uncertainty, we argue that the theory should abandon the requirements that narratives, in general, must lead to affective evaluation, and that they have to explain (and potentially simulate) all or even the bulk of the current decisional context. Evidence from studies of incidental learning show that narrative schemata can bias decisions while remaining fragmentary, insufficient for prediction, and devoid of utility values.

Unleashed expressions for cooperation are mainly based on the expected perceptual effects of behaviours and not the behaviours themselves. From an evolutionary viewpoint, this goal-directed mechanism allows for a comprehensive story for the theory proposed by Heintz & Scott-Phillips. Over the past 2 million years, this situated mechanism has been reused for tool use and the language development for hominids.

The “fearful ape hypothesis” is interesting but is currently underspecified. We need more research on whether it is specific to fear, specific to humans (or even cooperative breeders in general), what is included in “fear,” and whether these patterns would indeed evolve despite arms races to extract help from audiences. Specifying these will result in a more testable hypothesis.

A rational economic analysis complements Grossmann's fearful ape hypothesis. Two examples of mixed-motive games with strong inter-dependence (i.e., weak chirping nestling, boxed pigs) demonstrate that signaling weakness is a dominant strategy. Weakness elicits cooperative, caring response, comprising the equilibrium of the game. In extensive form, a reliable reputation of weakness elicits caring as a sequential equilibrium.

Theories are an integral part of the scientific endeavour. The target article proposes interesting ideas for a theory on human–robot interaction but lacks specificity that would enable us to properly test this theory. No empirical data are yet available to determine its predictive power.

Conviction Narrative Theory bears a close resemblance to the Theory of Narrative Thought, although the two were designed to address different questions. In this commentary, we detail some of the more pronounced similarities and differences and suggest that resolving the latter could produce a third theory of narrative cognition that is superior to either of these two.

Our commentary focuses on the interaction between Grossmann's fearful ape hypothesis (FAH) and the human self-domestication hypothesis (HSDH), also taking into account language acquisition and evolution. Although there is considerable overlap between the two hypotheses, there are also some discrepancies, and our goal is to consider the extent to which HSDH can explain the phenomena identified by FAH without invoking fearfulness as directly adaptive.

Heintz & Scott-Phillips's account of human expression leaves a number of central issues unclear – not least, whether the lack of expression in nonhuman species is attributable to their lack of the relevant metarepresentational abilities, an absence of trust, or a consequence of other factors. In place of their view, we propose a gradualistic account of the origins of human expression.

Although we find many merits to Grossmann's fearful ape hypothesis, unlike Grossmann, we see heightened fearfulness as an ontogenetic adaptation, signaling helplessness and fostering caregiving during infancy, which subsequently became exapted to promote cooperation. We also argue that, rather than being the “breeding ground” for enhanced infant fearfulness, cooperative care is more likely the evolved product of enhanced fearfulness.

Following the depiction theory by Clark and Fischer we would expect people interacting with robots to experience fictional emotions akin to those toward films or novels. However, some people's emotional reactions toward robots display the motivational force typical to non-fictional emotions. We discuss this incongruity and offer two suggestions on how to explain it while maintaining the depiction theory.

We challenge Johnson et al.'s assumption that people reduce unclear situations to a single narrative explanation and that such reduction would be adaptive for decision-making under radical uncertainty. Instead, we argue that people imagine and maintain multiple narrative possibilities throughout the decision-making process and that this process provides cognitive flexibility and adaptive benefits within the proposed model.

Heintz & Scott-Phillips propose that the partner choice ecology of our ancestors required Gricean cognitive pragmatics for reputation management, which caused a tendency toward showing and expecting prosociality that subsequently scaffolded language evolution. Here, we suggest a cognitively leaner explanation that is more consistent with comparative data and posits that prosociality and eventually language evolved along with cooperative breeding.

Grossmann's intriguing proposal can benefit from a more thorough integration of the primate literature, particularly on neophobia. Moreover, it directly leads to strong predictions in callitrichids, the only other cooperatively breeding primates beyond humans, which may indeed be met: Being more likely to signal distress than independently breeding monkeys, and responding to such signals with approach and affiliation.

Conviction Narrative Theory (CNT) is a convincing descriptive theory, and Johnson et al.'s formal model is a welcome contribution to building more precise, testable hypotheses. However, some extensions to the proposed model would make it better defined and more powerful. The suggested extensions enable the model to go beyond CNT, predicting choice outcomes and explaining affective phenomena.

Focusing on imagination and the social context in the generation of conviction narratives, we propose that these elements are dynamically related to one another, and crucially that it is the nature of this relationship that determines individuals' level of epistemic openness and capacity to respond adaptively to update their narratives in a way that increases the possibility of more successful decision-making.

Johnson et al. suggest that we rely on narratives to make choices under radical uncertainty. We argue that in its current version Conviction Narrative Theory (CNT) does not account for embodied, direct sensorimotor influences on choices under radical uncertainty that may bypass narratives, particularly in highly time-constrained situations. We therefore suggest to extend CNT by an embodied choice perspective.

Clark and Fischer analyze social robots as interactive depictions, presenting characters that people can interact with in social settings. Unlike other types of depictions, the props for social robot depictions depend on emerging interactive technologies. This raises questions about how such depictions depict: They conflate character and prop in ways that delight, confuse, mistreat, and may become ordinary human–technology interactions.

While the metarepresentational structure of ostensive communication may explain the unleashing of human expression, it neither explains the open-endedness of the thoughts expressed/communicated, nor how the multiply embedded nature of the metarepresentational structure invoked arose. These both require the recursivity of human language, a capacity which must be distinguished from external (public) languages and their use in communication.

Clark and Fischer's dismissal of extant human–robot interaction research approaches limits opportunities to understand major variables shaping people's engagement with social robots. Instead, this endeavour categorically requires multidisciplinary approaches. We refute the assumption that people cannot (correctly or incorrectly) represent robots as autonomous social agents. This contradicts available empirical evidence, and will become increasingly tenuous as robot automation improves.

Johnson et al. make a persuasive case that qualitative, story-like reasoning plays a crucial role in everyday thought and decision-making. This commentary questions the cohesiveness of this type of reasoning and the representations that generate it. Perhaps narratives do not underpin, but are ephemeral products of thought, created when we need to justify our actions to ourselves and others.

We agree with Heintz & Scott-Phillips that pragmatics does not supplement, but is prior to and underpins, language. Indeed, human non-linguistic communication is astonishingly rich, flexible, and subtle, as we illustrate through the game of charades, where people improvise communicative signals when linguistic channels are blocked. The route from non-linguistic charade-like communication to combinatorial language involves (1) local processes of conventionalization and grammaticalization and (2) spontaneous order arising from mutual constraints between different communicative signals.

We take up issues raised in the commentaries about our proposal that social robots are depictions of social agents. Among these issues are the realism of social agents, experiencing robots, communicating with robots, anthropomorphism, and attributing traits to robots. We end with comments about the future of social robots.

Social robots serve people as tutors, caretakers, receptionists, companions, and other social agents. People know that the robots are mechanical artifacts, yet they interact with them as if they were actual agents. How is this possible? The proposal here is that people construe social robots not as social agents per se, but as depictions of social agents. They interpret them much as they interpret ventriloquist dummies, hand puppets, virtual assistants, and other interactive depictions of people and animals. Depictions as a (...) class consist of three physical scenes with part-by-part mappings between them: (a) a base scene (the raw physical artifact), (b) the depiction proper (the artifact construed as a depiction), and (c) the scene depicted (the scene people are to imagine). With social robots, evidence shows people form the same three scenes plus mappings: They perceive the raw machinery of a robot, construe it as a depiction of a character, and, using the depiction as a guide, engage in the pretense that they are interacting with the character depicted. With social robots, people also recognize three classes of agents – the characters depicted, the intended recipients of the depictions (those who view or interact with the robots), and the authorities responsible for the robots (the designers, makers, and owners). Construing social robots as depictions, we argue, accounts for many phenomena not covered by alternative models. (shrink)

We agree with Grossmann that fear often builds cooperative relationships. Yet he neglects much extant literature. Prior researchers have discussed how fear (and other emotions) build cooperative relationships, have questioned whether fear per se evolved to serve this purpose, and have emphasized that human cooperation takes many forms. Grossmann's theory would benefit from a wider consideration of this work.

We present two challenges to the fearful ape hypothesis: (1) biobehavioral synchrony precedes and moderates the effects of fear on cooperative care, and (2) cooperative care emerges in a more bidirectional manner than Grossmann acknowledges. We present evidence demonstrating how dyadic differences in co-regulation and individual differences in infants' reactivity shape caregivers' responses to infant affect.

Homesign is a visual–gestural form of communication that emerges between deaf individuals and their hearing interlocutors in the absence of a conventional sign language. I argue here that homesign conversations form a perfect testcase to study the extent to which pragmatic competence is foundational rather than derived from our linguistic abilities.

A significant body of literature has identified how narrative provides a basis for perceiving and understanding human experience. In the target article, the authors arrive at the need for a form of narrative-based reasoning due to constraints that render probabilistic-based reasoning ineffective. This commentary attempts to bridge this gap and identify links between the proposed and existing theories.

Clark and Fischer's three levels of depiction of social robots can be conceptualized as cognitive schemas. When interacting with social robots, humans shift between schemas similarly to how they shift between identity category schemas when interacting with other humans. Perception of mind, context cues, and individual differences underlie perceptions of which level of depiction is most situationally relevant.

Grossmann posits that heightened fearfulness in humans evolved to facilitate cooperative caregiving. We argue that three of his claims – that children express more fear than other apes, that they are uniquely responsive to fearful expressions, and that expression and perception of fear are linked with prosocial behaviors – are inconsistent with existing literature or require additional supporting evidence.

The fearful ape hypothesis proposes that heightened fearfulness in humans is adaptive. However, despite its attractive anthropocentric narrative, the evidence presented for greater fearfulness in humans versus other apes is not sufficient to support this claim. Conceptualization, context, and comparison are strongly lacking in Grossmann's proposal, but are key to understanding variation in the fear response among individuals and species.

Grossmann's impressive article indicates that – along with attentional biases, expansion of domain-general processes of learning and memory, and other temperamental tweaks – heightened fearfulness is part of the genetic starter kit for distinctively human minds. The learned matching account of emotional contagion explains how heightened fearfulness could have promoted the development of caring and cooperation in our species.

Clark and Fischer (C&F) claim that trait attribution has major limitations in explaining human–robot interactions. We argue that the trait attribution approach can explain the three issues posited by C&F. We also argue that the trait attribution approach is parsimonious, as it assumes that the same mechanisms of social cognition apply to human–robot interaction.

While infant fearfulness, and its expression via crying, may have been adaptive in our evolutionary history, for modern parents, crying can be challenging to respond to. We discuss how and why prolonged crying can raise the risk for difficulties with adult care. Given that crying is the most-reported trigger for shaking, its potential to elicit maladaptive responses should not be overlooked.

When people interact with social robots, they treat them as real social agents. How people depict robots is fun to consider, but when people are confronted with embodied entities that move and talk – whether humans or robots – they interact with them as authentic social agents with minds, and not as mere representations.

Simulation – imagining future events – plays a role in decision-making. In Conviction Narrative Theory, people's emotional responses to their simulations inform their choices. Yet imagining one possible future also increases its plausibility and accessibility relative to other futures. We propose that the act of simulation, in addition to affective evaluation, drives people to choose in accordance with their simulations.

Johnson, Bilovich, and Tuckett set out a helpful framework for thinking about how humans make decisions under radical uncertainty and contrast this with classical decision theory. We show that classical theories assume so little about psychology that they are not necessarily in conflict with this approach, broadening its appeal.

We outline two points of criticism. Firstly, we argue that robots do constitute a separate category of beings in people's minds rather than being mere depictions of non-robotic characters. Secondly, we find that (semi-)automatic processes underpinning communicative interaction play a greater role in shaping robot-directed speech than Clark and Fischer's theory of social robots as depictions indicate.

Do people hold robots responsible for their actions? While Clark and Fischer present a useful framework for interpreting social robots, we argue that they fail to account for people's willingness to assign responsibility to robots in certain contexts, such as when a robot performs actions not predictable by its user or programmer.

The target article proposes that people perceive social robots as depictions rather than as genuine social agents. We suggest that people might instead view social robots as social agents, albeit agents with more restricted capacities and moral rights than humans. We discuss why social robots, unlike other kinds of depictions, present a special challenge for testing the depiction hypothesis.

I enjoyed reading this compelling account of Conviction Narrative Theory (CNT). As a theoretical neurobiologist, I recognised – and applauded – the tenets of CNT. My commentary asks whether its claims could be installed into a Bayesian mechanics of decision-making, in a way that would enable theoreticians to model, reproduce and predict decision-making.

I propose that the evolution of teaching has been central in extending manipulative intentions. Demonstrating may be the evolutionarily first form of expression that is productive, ostensive, and involves informative intention. Demonstration also involves theory of mind. Then pantomime goes a step further and involves a communicative intention. Pantomime can thereby function as displaced communication used for more complex expressions.

Clark and Fischer (C&F) discuss how people interact with social robots in the context of a general analysis of interaction with characters. I suggest that a consideration of aesthetic illusion would add nuance to this analysis. In addition, I illustrate how people's experiences with other depictions of characters require adjustments to C&F's claims.

Narratives and heuristics are both tools for dealing with uncertainty, intractability, and incommensurability, that is, for all real-world situations outside the domain of Bayesian decision theory. But how do narratives and heuristics relate? I suggest two links: Heuristics select narratives to explain events, and “big” narratives select the heuristics that people live by, to execute their values and moral principles.

We suggest that as people move to construe robots as social agents, interact with them, and treat them as capable of social ties, they might develop (close) relationships with them. We then ask what kind of relationships can people form with bots, what functions can bots fulfill, and what are the societal and moral implications of such relationships.

Clark and Fischer argue that people see social robots as depictions of social agents. However, people's interactions with virtual assistants may change their beliefs about social robots. Children and adults with exposure to virtual assistants may view social robots not as depictions of social agents, but as social agents belonging to a unique ontological category.

In the target article, Clark and Fischer argue that little is known about children's perceptions of social robots. By reviewing the existing literature we demonstrate that infants and young children interact with robots in the same ways they do with other social agents. Importantly, we conclude children's understanding that robots are artifacts (e.g., not alive) develops gradually during the preschool years.

We use screams to explore ideas presented in the target article. Evolving first in animals as a response to predation, screams reveal more complex social use in nonhuman primates and, in humans, uniquely, are associated with a much greater variety of emotional contexts including fear, anger, surprise, and happiness. This expansion, and the potential for manipulation, promotes listener social vigilance.

The case for the superiority of Conviction Narrative Theory (CNT) over probabilistic approaches rests on selective employment of a double standard. The authors judge probabilistic approaches inadequate for failing to apply to “grand-world” decision problems, while they praise CNT for its treatment of “small-world” decision problems. When both approaches are held to the same standard, the comparative question is murkier.

Human lives are radically uncertain. Making sense of such uncertainties is the hallmark of wisdom. Sense-making requires narratives, putting them in the center stage of human everyday decision-making. Yet what if radical uncertainty is a narrative itself? Moreover, do laypeople always consider such narratives irrational? Here we pose these questions to enrich a theory of choice under uncertainty.

Already as infants humans are more fearful than our closest living primate relatives, the chimpanzees. Yet heightened fearfulness is mostly considered maladaptive, as it is thought to increase the risk of developing anxiety and depression. How can this human fear paradox be explained? The fearful ape hypothesis presented herein stipulates that, in the context of cooperative caregiving and provisioning unique to human great ape group life, heightened fearfulness was adaptive. This is because from early in ontogeny fearfulness expressed and perceived (...) enhanced care-based responding and provisioning from, while concurrently increasing cooperation with, mothers and others. This explanation is based on a synthesis of existing research with human infants and children, demonstrating a link between fearfulness, greater sensitivity to and accuracy in detecting fear in others, and enhanced levels of cooperative behaviors. These insights critically advance current evolutionary theories of human cooperation by adding an early-developing affective component to the human cooperative makeup. Moreover, the current proposal has important cultural, societal, and health implications, as it challenges the predominant view in Western, educated, industrialized, rich, and democratic (WEIRD) societies that commonly construe fearfulness as a maladaptive trait, potentially ignoring its evolutionary adaptive functions. (shrink)

The fearful ape hypothesis (FAH) presents an evolutionary-developmental framework stipulating that in the context of cooperative caregiving, unique to human great ape group life, heightened fearfulness was adaptive. This is because from early in human ontogeny fearfulness expressed and perceived enhanced care-based responding and cooperation with mothers and others. This response extends and refines the FAH by incorporating the commentaries' suggestions and additional lines of empirical work, providing a more comprehensive and nuanced version of the FAH. Specifically, it encourages and (...) hopes to inspire cross-species and cross-cultural, longitudinal work elucidating evolutionary and developmental functions of fear in context. Beyond fear, it can be seen as a call for an evolutionary-developmental approach to affective science. (shrink)

Clark and Fischer propose that people interpret social robots not as social agents, but as interactive depictions. Drawing on research focusing on how children selectively learn from social others, we argue that children do not view social robots as interactive toys but instead treat them as social learning partners and critical sources of information.

Fear can undermine cooperation. It may discourage individuals from collaborating with others because of concerns about potential exploitation; prompt them to engage in defensive aggression by launching a preemptive strike; and propel power-seeking individuals to act dominantly rather than compassionately. Therefore, accumulated evidence requires a more contextualized consideration of the link between fear and cooperation in adults.

Social robots have limited social competences. This leads us to view them as depictions of social agents rather than actual social agents. However, people also have limited social competences. We argue that all social interaction involves the depiction of social roles and that they originate in, and are defined by, their function in accounting for failures of social competence.

One of our main goals with “Expression unleashed” was to highlight the distinctive, ostensive nature of human communication, and the many roles that ostension can play in human behavior and society. The commentaries we received forced us to be more precise about several aspects of this thesis. At the same time, no commentary challenged the central idea that the manifest diversity of human expression is underpinned by a common cognitive unity. Our reply is organized around six issues: (1) languages and (...) their cultural evolution; (2) the pervasiveness of expression in human behavior; (3) artificial intelligence and ostensive communication; (4) communication in other animals; (5) the ecology and evolution of ostensive communication; and (6) biolinguistics and pragmatics. (shrink)

Human expression is open-ended, versatile, and diverse, ranging from ordinary language use to painting, from exaggerated displays of affection to micro-movements that aid coordination. Here we present and defend the claim that this expressive diversity is united by an interrelated suite of cognitive capacities, the evolved functions of which are the expression and recognition of informative intentions. We describe how evolutionary dynamics normally leash communication to narrow domains of statistical mutual benefit, and how expression is unleashed in humans. The relevant (...) cognitive capacities are cognitive adaptations to living in a partner choice social ecology; and they are, correspondingly, part of the ordinarily developing human cognitive phenotype, emerging early and reliably in ontogeny. In other words, we identify distinctive features of our species' social ecology to explain how and why humans, and only humans, evolved the cognitive capacities that, in turn, lead to massive diversity and open-endedness in means and modes of expression. Language use is but one of these modes of expression, albeit one of manifestly high importance. We make cross-species comparisons, describe how the relevant cognitive capacities can evolve in a gradual manner, and survey how unleashed expression facilitates not only language use, but also novel behaviour in many other domains too, focusing on the examples of joint action, teaching, punishment, and art, all of which are ubiquitous in human societies but relatively rare in other species. Much of this diversity derives from graded aspects of human expression, which can be used to satisfy informative intentions in creative and new ways. We aim to help reorient cognitive pragmatics, as a phenomenon that is not a supplement to linguistic communication and on the periphery of language science, but rather the foundation of the many of the most distinctive features of human behaviour, society, and culture. (shrink)

Children's cooperation with peers undergoes substantial developmental changes between 3 and 10 years of age. Here we stipulate that young children's initial fearfulness of peers' behaviour develops into older children's fearfulness of peers' evaluations of their own behaviour. Cooperation may constitute an adaptive environment in which the expressions of fear and self-conscious emotions regulate the quality of children's peer relationships.

Grossmann's argument for the “fearful ape hypothesis” rests on an incomplete review of infant responses to emotional faces. An alternate interpretation of the literature argues the opposite, that an early preference for happy faces predicts cooperative learning. Questions remain as to whether infants can interpret affect from faces, limiting the conclusion that any “fear bias” means the infant is fearful.

While we applaud the careful breakdown by Clark and Fischer of the representation of social robots held by the human user, we emphasise that a neurocognitive perspective is crucial to fully capture how people perceive and construe social robots at the behavioural and brain levels.

While Conviction Narrative Theory correctly criticizes utility-based accounts of decision-making, it unfairly reduces probabilistic models to point estimates and treats affect and narrative as mechanistically opaque yet explanatorily sufficient modules. Hierarchically nested Bayesian accounts offer a mechanistically explicit and parsimonious alternative incorporating affect into a single biologically plausible precision-weighted mechanism that tunes decision-making toward narrative versus sensory dependence under varying uncertainty levels.

Conviction Narrative Theory (CNT) is a theory of choice under radical uncertainty – situations where outcomes cannot be enumerated and probabilities cannot be assigned. Whereas most theories of choice assume that people rely on (potentially biased) probabilistic judgments, such theories cannot account for adaptive decision-making when probabilities cannot be assigned. CNT proposes that people use narratives – structured representations of causal, temporal, analogical, and valence relationships – rather than probabilities, as the currency of thought that unifies our sense-making and decision-making (...) faculties. According to CNT, narratives arise from the interplay between individual cognition and the social environment, with reasoners adopting a narrative that feels “right” to explain the available data; using that narrative to imagine plausible futures; and affectively evaluating those imagined futures to make a choice. Evidence from many areas of the cognitive, behavioral, and social sciences supports this basic model, including lab experiments, interview studies, and econometric analyses. We identify 12 propositions to explain how the mental representations (narratives) interact with four inter-related processes (explanation, simulation, affective evaluation, and communication), examining the theoretical and empirical basis for each. We conclude by discussing how CNT can provide a common vocabulary for researchers studying everyday choices across areas of the decision sciences. (shrink)

Whereas most commentators agree about the centrality of narratives in decision-making, the commentaries revealed little consensus about the nature of radical uncertainty. Here we consider thirteen objections to our views, including our characterization of the uncertain decision environment and associated cognitive, affective, and social processes. We conclude that under radical uncertainty, narratives rather than probabilities are the currency of thought.

By structuring information in a systematic relational framework, narratives are cultural attractors that are particularly well-suited for transmission. The relational structure of narrative is partly what communicates causality, but this structure also complicates both transmission and selection on cultural elements by introducing correlations among narrative elements and between different narratives. These correlations have implications for adaptation, complexity, and robustness.

Grossmann presents an exciting and interesting theory on the function of fearfulness. In this commentary it is argued that fearfulness may be a byproduct of a larger executive functioning network and these early regulatory skills considered more broadly may be key building blocks for later cooperative behaviors.

Conviction Narrative Theory is an interesting and plausible way to think about how individuals make decisions when quantitative assessments are not open to them. The question I pose is the following. Is there any general result about how decisions should be taken independent of the particular circumstances of that decision?

Grossmann used evolutionary analysis to argue for the adaptive nature of fearfulness. This analysis, however, falls short of addressing why negative affectivity is maladaptive in contemporary Western societies. Here, we fill the gap by documenting the implied cultural variation and considering cultural (rather than biological) evolution over the last 10,000 years to explain the observed cultural variation.

In his article, Grossmann argues that, in the context of human cooperative caregiving, heightened fearfulness in children and human sensitivity to fear in others are adaptive traits. I offer and briefly defend a rival hypothesis: Heightened fearfulness among infants and young children is a maladaptive trait that did not get deselected in the process of evolution because human sensitivity to fear in others mitigates its disadvantageous effects to a sufficient extent.

Johnson et al. make a strong case for Conviction Narrative Theory, but it remains unclear why so many adaptive narratives include supernatural causes and other falsehoods. Focusing on religions, I argue that an adaptive decision-making system might include supernatural falsehoods because they simplify complex problems, they are sensitive to long-term incentives, and they evoke strong emotions in a communicative context.

We propose extrapolating Conviction Narrative Theory (CNT) to clinical psychology and psychiatry. We demonstrate how CNT principles may benefit assessment, therapy, and possibly even modify public health views of neuropsychiatric disorders. Our commentary focuses on hoarding disorder as a model, elaborates on discrepancies in the scientific literature and suggests how the CNT may resolve them.

The authors at times propose that robots are mere depictions of social agents (a philosophical claim) and at other times that people conceive of social robots as depictions (an empirical psychological claim). We evaluate each claim's accuracy both now and in the future and, in doing so, we introduce two dangerous misperceptions people have, or will have, about social robots.

I encourage Johnson et al. to ground Conviction Narrative Theory in more detail in foundational, earlier decision-making research – first and foremost in Herbert Simon's work. Moreover, I wonder if and how further reflections about narratives could aid tackling two interrelated grand challenges of the decision sciences: To describe decision-making environments; to understand how people select among decision-strategies in environments.

Humans are not only fearful apes, but we also communicate our fear using social cues. Social fear displays typically elicit care and assistance in the real world and the lab. But in the psychology and neuroscience literature fearful expressions are commonly interpreted as “threat cues.” The fearful ape hypothesis suggests that fearful expressions should be instead considered appeasement and vulnerability cues.

We review research suggesting that several of the functions attributed to fear, in the target article's fearful ape hypothesis, also apply to supplication and appeasement emotions. These emotions facilitate support provisioning from others and the formation and maintenance of cooperative relationships. We therefore propose that the fearful ape hypothesis be expanded to include several other distinctively human emotional tendencies.

We challenge the proposal that partner-choice ecology explains the evolutionary emergence of ostensive communication in humans. The good fit between these domains might be because of the opposite relation (ostensive communication promotes the evolution of cooperation) or because of the dependence of both these human-specific traits on a more ancient contributor to human cognitive evolution: the use of technology.

We connect Conviction Narrative Theory to an account that views people as intuitive scientists who can flexibly create, evaluate, and modify representations of decision problems. We argue that without understanding how the relevant complex narratives (or indeed any representation, simple to complex) are themselves constructed, we also cannot know when and why people would rely on them to make choices.

Grossmann proposes the “fearful ape hypothesis,” suggesting that heightened fearfulness in early life is evolutionarily adaptive. We question this claim with evidence that (1) perceived fearfulness in children is associated with negative, not positive long-term outcomes; (2) caregivers are responsive to all affective behaviors, not just those perceived as fearful; and (3) caregiver responsiveness serves to reduce perceived fearfulness.

The fearful ape hypothesis revolves around our ability to express and perceive fearfulness. Here, we address these abilities from a social learning perspective which casts fearfulness in a slightly different light. Our commentary argues that any theory that characterizes a (human) social signal as being adaptive, needs to address the role of social learning as an alternative candidate explanation.

Clark and Fischer's depiction hypothesis is based on examples of western mimetic art. Yet social robots do not depict social interactions, but instead perform them. Similarly, dance and performance art do not rely on depiction. Kinematics and expressivity are better predictors of dance aesthetics and of effective social interactions. In this way, social robots are more like dancers than actors.

As Heintz & Scott-Phillips rightly argued, pragmatics has been too commonly considered as a supplement to linguistic communication. Their aim to reorient the study of cognitive pragmatics as the foundation of many distinctive features of human behavior finds echo in the neuropsychological literature on tool use, in which the investigation of semantic dementia challenges the classical semantics versus pragmatics dissociation.

This commentary focuses on affective structures and the main adaptive functions of shared narratives to fill the gaps of the Conviction Narrative Theory. The transmission of narratives among individuals in highly uncertain situations is irrevocably tainted by affects and anchored in collective memory. Narratives have important evolutionary functions for human beings under threat and act as the social glue that creates and strengthens social bonds among individuals.

We question the role given to depiction in Clark and Fischer's account of interaction with social robots. Specifically, we argue that positing a unique cognitive process for handling depiction is evolutionarily implausible and empirically redundant because the phenomena it is intended to explain are not limited to depictive contexts and are better explained by reference to more general cognitive processes.

Drawing from two strands of ecological psychology, we suggest that even if social robots are interactive depictions, people need not mentally represent them as such. Rather, people can engage with the opportunities for action or affordances that social robots offer to them. These affordances are constrained by the larger sociocultural settings within which human–robot interactions occur.

Interactions with social robots are symbolic experiences guided by the pretense that robots depict real people. But they can also be natural experiences that are direct, automatic, and independent of any thoughtful mapping between what is real and depicted. Both experiences are important, both may apply within the same interaction, and they may vary within a person over time.

In the fearful ape hypothesis, Grossmann argues that heightened fearfulness increases human-unique cooperation. We suggest that this conclusion, however, may be premature. In particular, we question Grossmann's singling out of fear as the affective trait that enhances cooperative care. Additionally, we problematize the extent to which heightened fearfulness in humans, and its association with human-unique cooperation, are supported empirically.

The target article highlights the sources of open-endedness of human communication. However, the authors' perspective does not account for the structure of particular communication systems. To this end, we extend the authors' perspective, in the spirit of evolutionary extended synthesis, with a detailed account of the sources of constraints imposed upon expression in the course of child development.

Heintz & Scott-Phillips's hypothesis that the topic range and type diversity of human expressive communication gains support from consilience with prior accounts of market exchange as fundamental to unique human niche construction, and of mindshaping as much more important than mindreading. The productivity of the idea is illustrated by the light it might shed on why elephants seem to engage in continuous social communication for little evident purpose.

There are reasons to suspect that meta-cognition about construing social robots as depictions would be more difficult – or absent – than Clark and Fischer discuss. Self-reports about the cognitive processes involved might therefore tend to be incomplete or inaccurate, limiting their usefulness as measures.

Conviction Narrative Theory holds that reasoners adopt “a narrative that feels ‘right’ to explain the available data” and use “that narrative to imagine plausible futures” (target article, Abstract). Drawing on feelings-as-information theory, this commentary reviews the role of metacognitive experiences of ease or difficulty and highlights that fluently processed narratives are more likely to “feel right.”.

The depiction model presents a major advance in our theoretical conceptualization of how humans experience and understand social robots. But the scope of the model is, I suggest, more limited: It pertains to one possible phase in a more comprehensive cognitive-practical dynamics of sense-making (“sociomorphing”) as conceptualized in the OASIS framework. According to the OASIS framework, some basic social actions can be realized by robots, while others may be depicted in the way described by the model.

Education often relies on an implicit assumption that decisions are made rationally, and focuses on situations in which there are correct answers that can be known with certainty. The proposal that decision-making is often narrative, especially in contexts of radical uncertainty, suggests important changes to education practice and new questions for education research.

The target article posits that caregiver cooperation rendered heightened expression of childhood fear an adaptive response to threat. I argue that caregiver cooperation rendered childhood fear expression less accurate as a signal of actual threat, and hence less effective for harm avoidance. Further, other emotional expressions that avoid unwarranted caregiver stress may be more likely to evoke needed care.

In his ‘script theory,' Tomkins first proposed that people unconsciously organize their life experiences in terms of narrative structures he termed “scripts.” I use a clinical vignette to illustrate how the psychotherapeutic process of “making the unconscious conscious” involves becoming aware of the maladaptive scripts that people unwittingly live by, and developing them into the “conviction narratives” proposed by the authors.

Convincing narratives are not confabulations. Presumably they “feel right” to decision-making agents because the probabilities they assign intuitively (i.e., implicitly) to potential outcomes are plausible. Can we render explicit the calculations that would be performed by a decision-making agent to evaluate the plausibility of competing narratives? And if we can, what, exactly, makes a narrative “feel right” to an agent?

This commentary presents two illustrations, from the world of poker, of the continuity between linguistic and non-linguistic communication and expression, in support of Heintz & Scott-Phillips's account of the evolution of human expression and communication. I also come across the presumption of relevance in the context of a poker table.

The “fearful ape hypothesis” could be regarded as one aspect of a more general “suffering ape hypothesis”: Humans are more likely to experience negative emotions (e.g., fear, sadness), aversive symptoms (e.g., pain, fever), and to engage in self-harming behavior (e.g., cutting, suicide attempts) because these might motivate affiliative, consolatory, and supportive behavior from their prosocial environment thereby enhancing evolutionary fitness.

Clark and Fischer argue that humans treat social artifacts as depictions. In contrast, theories of distributed cognition suggest that there is no clear line separating artifacts from agents, and artifacts can possess agency. The difference is likely a result of cultural framing. As technology and artificial intelligence grow more sophisticated, the distinction between depiction and agency will blur.

The problem of generating generally capable agents is an important frontier in artificial intelligence (AI) research. Such agents may demonstrate open-ended, versatile, and diverse modes of expression, similar to humans. We interpret the work of Heintz & Scott-Phillips as a minimal sufficient set of socio-cognitive biases for the emergence of generally expressive AI, separate yet complementary to existing algorithms.

Conviction Narrative Theory (CNT) is conceptually so multifaceted as to make critical evaluation difficult. It also omits one course of action: Active engagement with the world. Parsing the developmental and mechanistic processes within CNT would allow for a rigorous research programme to put the account under test. I propose a unifying account based on active inference.

In order to address why the number of patients suffering from anxiety and depression are seemingly exploding in Western, educated, industrialized, rich, and democratic (WEIRD) countries, it is sensible to look at the evolution of human fearfulness responses. Here, we draw on Veit's pathological complexity framework to advance Grossmann's goal of re-characterizing human fearfulness as an adaptive trait.

Why is it that people simultaneously treat social robots as mere designed artefacts, yet show willingness to interact with them as if they were real agents? Here, we argue that Dennett's distinction between the intentional stance and the design stance can help us to resolve this puzzle, allowing us to further our understanding of social robots as interactive depictions.

Heintz & Scott-Phillips provide a useful synthesis for constructing a bridge between work by both cognitive scientists and evolutionary biologists studying the diversity of human communication. Here, we aim to strengthen their bridge from the side of evolutionary biology, to argue that we can best understand ostensive communication as a scaffold for more complex forms of intentional expressions.

The relation between communication partners is crucial for the success of their interaction. This is also true for artificial social agents. However, the more we engage in artificial relationships, the more we are forced to regulate and control them. I refer to this as binding paradox. This deserves attention during technological developments and requires professional supervision during ongoing interactions.

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.

The authors present an ambitious attempt to outline the gradual evolution of the cognitive foundations of ostensive communication. We focus on three problematic aspects of the distinction between expression and communication: ambiguity in the distinction's central principle of “complementary mechanisms,” inconsistencies in the application of the distinction across taxa, and the dismissal of mentalizing in nonhuman primates.

How do we switch between “playing along” and treating robots as technical agents? We propose interaction breakdowns to help solve this “social artifact puzzle”: Breaks cause changes from fluid interaction to explicit reasoning and interaction with the raw artifact. These changes are closely linked to understanding the technical architecture and could be used to design better human–robot interaction (HRI).

Grossmann proposes an interesting framework to explain how heightened fearfulness among humans could be evolutionarily adaptive in the context of cooperative care. I would like to propose that cooperative care may also be a potential mechanism promoting enhanced happiness expression among humans, shedding light on questions about the scope and boundary of the fearful ape hypothesis.

In this commentary we would like to question (a) Clark and Fischer's characterization of the “social artifact puzzle” – which we consider less puzzling than the authors, and (b) their account of social robots as depictions involving three physical scenes – which to us seems unnecessarily complex. We contrast the authors' model with a more parsimonious account based on attributions.

According to Grossmann, the high levels of cooperation seen in humans are the result of a “virtuous caring cycle” on which the increased care that more fearful children receive brings increased cooperative tendencies in those children. But this proposal overlooks an equally well supported alternative on which children's anxiety – not a virtuous caring cycle – explains the cooperative tendencies of humans.