Stephen Andrew Butterfill

Are these different requirements, in the sense that someone could satisfy one without satisfying the other? No one could meet the Truth Requirement without meeting the Variation Requirement, because understanding that a belief is false involves realising one should not believe it and appreciating the possibility of having other beliefs in its place. But could someone meet the Variation Requirement without meeting the Truth Requirement? In other words, is it possible to be aware of beliefs which are inconsistent without being aware that at least one of these beliefs is false?

People walk, build, paint and otherwise act together with a purpose in myriad ways. What is the relation between the actions people perform in acting together with a purpose and the outcome, or outcomes, to which their actions are directed? We argue that fully characterising this relation will require appeal not only to intention, knowledge and other familiar philosophical paraphernalia but also to another kind of representation involved in preparing and executing actions, namely motor representation. If we are right, motor representation plays a central role in the story of acting together.

Sensitivity to others’ actions is essential for social animals like humans and a fundamental requirement for any kind of social cognition. Unsurprisingly, it is present in humans from early in the first year of life. But what processes underpin infants’ sensitivity to others’ actions? Any attempt to answer this question must solve twin puzzles about the development of goal tracking. Why does some, but not all, of infants’ goal tracking appear to be limited by their abilities to represent the observed action motorically at the time it occurs? And why does their sensitivity to action sometimes manifest itself differently in dishabituation, pupil dilation and anticipatory looking? Solving these twin puzzles is critical for understanding humans’ earliest sensitivity to others’ actions. After introducing the puzzles, this paper argues that solving them may require identifying multiple, distinct processes for tracking the targets and goals of actions.

Current theory-of-mind research faces the challenge of reconciling two sets of seemingly incompatible findings: Whereas children come to solve explicit verbal false belief tasks from around 4years of age, recent studies with various less explicit measures such as looking time, anticipatory looking, and spontaneous behavior suggest that even infants can succeed on some FB tasks. In response to this tension, two-systems theories propose to distinguish between an early-developing system, tracking simple forms of mental states, and a later-developing system, based on fully developed concepts of belief and other propositional attitudes. One prediction of such theories is that the early-developing system has signature limits concerning aspectuality. We tested this prediction in two experiments. The first experiment showed that 2- and 3-year-olds take into account a protagonist's true or false belief about the location of an object in their active helping behavior. In contrast, toddlers' helping behavior did not differentiate between true and false belief conditions when the protagonist's belief essentially involved aspectuality. Experiment 2 replicated these findings with a more stringent method designed to rule out more parsimonious explanations. Taken together, the current findings are compatible with the possibility that early theory-of-mind reasoning is subject to signature limits as predicted by the two-systems account.

What enables individuals to act together? Recent discoveries suggest that a variety of mechanisms are involved. But something fundamental is yet to be investigated. In joint action, agents represent a collective goal, or so it is often assumed. But how, if at all, are collective goals represented in joint action and how do such representations impact performance? To investigate this question we adapted a bimanual paradigm, the circle-line drawing paradigm, to contrast two agents acting in parallel with two agents performing a joint action. Participants were required to draw lines or circles while observing circles or lines being drawn. The findings indicate that interpersonal motor coupling may occur in joint but not parallel action. This suggests that participants in joint actions can represent collective goals motorically.

ABSTRACT In what sense is commitment essential to joint action, and do the participants in a joint action themselves perceive commitment as essential? Attempts to answer this question have so far been hampered by clashes of intuition. Perhaps this is because the intuitions in question have mostly been investigated using informal methods only. To explore this possibility, we adopted a more formal approach to testing intuitions about joint action, sampling naïve participants’ intuitions about experimentally controlled scenarios. This approach did reveal patterns in participants’ responses which may hint at potential conceptual links between commitment and joint action. It did not however provide evidence to support the view that commitment is essential to joint action, at least not from the agents’ own perspective. We conclude that intuitions alone, even when drawn systematically from a large sample, may be a poor basis for theorizing about joint action.

Anticipatory looking on mindreading tasks can indicate our expectation of an agent's action. The challenge is that social situations are often more complex, involving instances where we need to track an agent's false belief to successfully identify the outcome to which an action is directed. If motor processes can guide how action goals are understood, it is conceivable— where that kind of goal ascription occurs in false-belief tasks— for motor representations to account for someone's belief-like state. Testing adults (N = 42) in a real-time interactive helping scenario, we discovered that participants' early mediolateral motor activity (leftwards– rightwards leaning on balance board) foreshadowed the agent's belief-based action preparation. These results suggest fast belief-tracking can modulate motor representations generated in the course of one's interaction with an agent. While adults' leaning, and anticipatory looking, revealed the contribution of fast false-belief tracking, participants did not correct the agent's mistake in their final helping action. These discoveries suggest that adults may not necessarily use another's belief during overt social interaction or find reflecting on another's belief as being normatively relevant to one's own choice of action. Our interactive task design offers a promising way to investigate how motor and mindreading processes may be variously integrated.

The development of children’s minds raises fundamental psychological and scientific questions, from how we are able to know about and describe basic aspects of the world such as words, numbers and colours to how we come to grasp causes, actions and intentions. This is the first book to properly introduce and examine philosophical questions concerning children’s cognitive development and considers the implications of scientific breakthroughs for the philosophy of developmental psychology. Each chapter explores a central topic in developmental psychology from a philosophical perspective: social interaction and the developing mind children's awareness of objects and the question of 'object permanence' knowledge of numbers children and the acquisition of knowledge of colour language acquisition and the 'mapping problem' children's knowledge of the relation between actions and goals belief acquisition and the developing mind. Throughout the book Stephen Butterfill draws on several important case studies, including experiments with children on memory, ‘false belief tasks’, and the process by which children come to see other people, not just themselves, as capable of experience. He shows how these questions can illuminate some fundamental debates in philosophy of mind, such as the mind’s possession of concepts, rationality and the mind, the possibility of objective thought, and the nature of perceptual experience. Additional features, such as chapter summaries, annotated further reading and a glossary provide helpful tools for those coming to the subject for the first time.

Few things matter more than the mental states of those nearby. Their ignorance defines limits on cooperation and presents opportunities to exploit in competition. What others feel, see and know can also provide information about events otherwise beyond your ken. It’s no surprise, then, that abilities to track others’ mental states are widespread. Many animals, including scrub jays, ravens, goats, dogs, ring-tailed lemurs, monkeys and chimpanzees, reliably vary their actions in ways that are appropriate given facts about another’s mental states. What underpins such abilities to track others’ mental states?

Our motor system can generate representations which carry information about the goals of another agent's actions. However, it is not known whether motor representations play a deeper role in social understanding, and, in particular, whether they enable tracking others' beliefs. Here we show that, for adult observers, reliably manifesting an ability to track another's false belief critically depends on representing the agent's potential actions motorically. One signature of motor representations is that they can be disrupted by constraints on an observed agent's action capacities. We therefore used a `mummification' technique to manipulate whether the agent in a visual ball-detection task was free to act or whether he was visibly constrained from acting. Adults' reaction times reliably reflected the agent's beliefs only when the agent was free to act on the ball and not when the agent was visibly constrained from acting. Furthermore, it was the agent's constrained action capabilities, rather than any perceptual novelty, that determined whether adult observers' reaction times reliably reflected the agent's beliefs. These findings signal that our motor system may underpin more of social cognition than previously imagined, and, in particular, that motor representations may underpin automatic false-belief tracking.

It is normally assumed that there is only one kind of purposive action. This article argues that there are two kinds of purposive action, which require different models of explanation. One kind of action is done without awareness of reasons; another kind of action is done because the agent is aware of reasons for that action. The argument starts by noting that philosophers disagree about what explains action. Some claim that actions are explained by impersonal facts, such as facts about how things should be or have been historically (e.g. Millikan, Stout). Others claim that actions are explained by mental states, such as beliefs and desires (e.g. Davidson, Velleman). These philosophers are usually regarded as offering conflicting accounts of one thing. However, they are best understood as giving accounts of different models of action‐explanation. Neither model fits every case, so there are at least two kinds of purposive action.

Anyone who has ever walked, cooked or crafted with a friend is in a position to know that acting jointly is not just acting side-by-side. But what distinguishes acting jointly from acting in parallel yet merely individually? Four decades of philosophical research have yielded broad consensus on a strategy for answering this question. This strategy is \emph{mechanistically committed}; that is, it hinges on invoking states of the agents who are acting jointly (often dubbed ‘shared’, ‘we-’ or ‘collective’ intentions). Despite the consensus, enduring disagreement remains. The disagreement may be a consequence of the strategy; at least this is plausible enough to motivate considering the prospects for an alternative. Our aim is therefore to draw attention to a coherent alternative that is present in the literature but often overlooked. This alternative is \emph{mechanistically neutral}: it avoids invoking states of agents. Implementing the alternative, we introduce the notion of a collective goal and a characterisation of acting jointly which meets criteria standardly used in evaluating other accounts and may have some advantages over those accounts.

Our motor system can generate representations which carry information about the goals of another agent's actions. However, it is not known whether motor representations play a deeper role in social understanding, and, in particular, whether they enable tracking others' beliefs. Here we show that, for adult observers, reliably manifesting an ability to track another's false belief critically depends on representing the agent's potential actions motorically. One signature of motor representations is that they can be disrupted by constraints on an observed agent's action capacities. We therefore used a `mummification' technique to manipulate whether the agent in a visual ball-detection task was free to act or whether he was visibly constrained from acting. Adults' reaction times reliably reflected the agent's beliefs only when the agent was free to act on the ball and not when the agent was visibly constrained from acting. Furthermore, it was the agent's constrained action capabilities, rather than any perceptual novelty, that determined whether adult observers' reaction times reliably reflected the agent's beliefs. These findings signal that our motor system may underpin more of social cognition than previously imagined, and, in particular, that motor representations may underpin automatic false-belief tracking.

People walk, build, paint and otherwise act together with a purpose in myriad ways. What is the relation between the actions people perform in acting together with a purpose and the outcome, or outcomes, to which their actions are directed? We argue that fully characterising this relation will require appeal not only to intention, knowledge and other familiar philosophical paraphernalia but also to another kind of representation involved in preparing and executing actions, namely motor representation. If we are right, motor representation plays a central role in the story of acting together.