Bertram F. Malle

Moral psychology—broadly speaking, the study of how people reason and act morally—has a long and productive history. Initially a subfield of philosophy, it posed groundbreaking questions about the nature of values and virtues, the balance of reason and emotion, and the gap between “is” and “ought.” In the twentieth century, the rise of psychology expanded the a priori philosophical enterprise into an empirical science. In psychology, perspectives of development, social interaction, cognition, and neuroscience brought new understanding and new questions. Over the past few decades, moral psychology has emerged as one of the most vital fields in the human sciences. The Cambridge Handbook of Moral Psychology offers a state-of-the-art guide to this rapidly expanding field. It introduces central questions and recent insights, traces continuing puzzles and debates, and integrates empirical and theoretical perspectives. The interdisciplinary character of the volume reflects the fact that contemporary research in moral psychology is deeply informed by many disciplines and traditions, from its philosophical roots to its latest scientific discoveries in psychology, anthropology, sociology, behavioral economics, and more.

Even though morally competent artificial agents have yet to emerge in society, we need insights from empirical science into how people will respond to such agents and how these responses should inform agent design. Three survey studies presented participants with an artificial intelligence agent, an autonomous drone, or a human drone pilot facing a moral dilemma in a military context: to either launch a missile strike on a terrorist compound but risk the life of a child, or to cancel the strike to protect the child but risk a terrorist attack. Seventy-two percent of respondents were comfortable making moral judgments about the AI in this scenario and fifty-one percent were comfortable making moral judgments about the autonomous drone. These participants applied the same norms to the two artificial agents and the human drone pilot. However, people ascribed different patterns of blame to humans and machines as a function of the agent’s decision of how to solve the dilemma. These differences in blame seem to stem from different assumptions about the agents’ embeddedness in social structures and the moral justifications those structures afford. Specifically, people less readily see artificial agents as embedded in social structures and, as a result, they explained and justified their actions differently. As artificial agents will perform many actions with moral significance, we must heed such differences in justifications and blame and probe how they affect our interactions with those agents.

People’s folk theory of consciousness encompasses three prototypes of conscious mental functioning: monitoring (awareness), choice, and subjective experience. All three are embedded in a broader folk theory of mind and thus closely linked to the concept of intentionality, action explanation, and a conception of free will. At least some of the prototypes of consciousness play a critical role in the assignment of personhood and responsibility. Recent discussions question the viability of folk conceptions of consciousness in light of work on the unconscious and neuroscience. Thus far this work appears to complement folk conceptions without contradicting them.

According to previous research, threatening people’s belief in free will may undermine moral judgments and behavior. Four studies tested this claim. Study 1 used a Velten technique to threaten people’s belief in free will and found no effects on moral behavior, judgments of blame, and punishment decisions. Study 2 used six different threats to free will and failed to find effects on judgments of blame and wrongness. Study 3 found no effects on moral judgment when manipulating general free will beliefs but found strong effects when manipulating the perceived choice capacity of the judged agent. Study 4 used pretested narratives that varied agents’ apparent free will and found that perceived choice capacity mediated the relationship between free will and blame. These results suggest that people’s general beliefs about whether free will exists have no impact on moral judgments but specific judgments about the agent’s choice capacity do.

Joint attention (JA) is hypothesized to have a close relationship with developing theory of mind (ToM) capabilities. We tested the co-occurrence of ToM and JA in social interactions between adults with no reported history of psychiatric illness or neurodevelopmental disorders. Participants engaged in an experimental task that encouraged nonverbal communication, including JA, and also ToM activity. We adapted an in-lab variant of experience sampling methods (Bryant, Coffey, Povinelli, & Pruett, 2013) to measure ToM during JA based on participants’ subjective reports of their thoughts while performing the task. This experiment successfully elicited instances of JA in 17/20 dyads. We compared participants’ thought contents during episodes of JA and non-JA. Our results suggest that, in adults, JA and ToM may occur independently.

This article explores several entanglements between human judgments of intentionality and morality (blame and praise). After proposing a model of people’s folk concept of intentionality I discuss three topics. First, considerations of a behavior’s intentionality a ff ect people’s praise and blame of that behavior, but one study suggests that there may be an asymmetry such that blame is more affected than praise. Second, the concept of intentionality is constitutive of many legal judgments (e.g., of murder vs. manslaughter), and one study illustrates people’s subtle considerations of intentionality in making those judgments. Third, controversial recent studies suggest that moral considerations can affect judgments of intentionality, and an asymmetry may exist such that blame a ff ects those judgments more than praise. I report two new studies that may shed light on these recent findings, and I discuss several theoretical models that might account for the impact of moral considerations on intentionality judgments and for the relationship between the two more generally.

Robot ethics encompasses ethical questions about how humans should design, deploy, and treat robots; machine morality encompasses questions about what moral capacities a robot should have and how these capacities could be computationally implemented. Publications on both of these topics have doubled twice in the past 10 years but have often remained separate from one another. In an attempt to better integrate the two, I offer a framework for what a morally competent robot would look like and discuss a number of ethical questions about the design, use, and treatment of such moral robots in society. Instead of searching for a fixed set of criteria of a robot’s moral competence I identify the multiple elements that make up human moral competence and probe the possibility of designing robots that have one or more of these human elements, which include: moral vocabulary; a system of norms; moral cognition and affect; moral decision making and action; moral communication. Juxtaposing empirical research, philosophical debates, and computational challenges, this article adopts an optimistic perspective: if robotic design truly commits to building morally competent robots, then those robots could be trustworthy and productive partners, caretakers, educators, and members of the human community. Moral competence does not resolve all ethical concerns over robots in society, but it may be a prerequisite to resolve at least some of them.

Can an event’s blameworthiness distort whether people see it as intentional? In controversial recent studies, people judged a behavior’s negative side effect intentional even though the agent allegedly had no desire for it to occur. Such a judgment contradicts the standard assumption that desire is a necessary condition of intentionality, and it raises concerns about assessments of intentionality in legal settings. Six studies examined whether blameworthy events distort intentionality judgments. Studies 1 through 4 show that, counter to recent claims, intentionality judgments are systematically guided by variations in the agent’s desire, for moral and nonmoral actions alike. Studies 5 and 6 show that a behavior’s negative side effects are rarely seen as intentional once people are allowed to choose from multiple descriptions of the behavior. Specifically, people distinguish between “knowingly” and “intentionally” bringing about a side effect, even for immoral actions. These studies suggest that intentionality judgments are unaffected by a behavior’s blameworthiness.

P.F. Strawson famously argued that reactive attitudes and ordinary moral practices justify moral assessments of blame, praise, and punishment. Here we consider whether Strawson's approach can illuminate the concept of desert. After reviewing standard attempts to analyze this concept and finding them lacking, we suggest that to deserve something is to justifiably receive a moral assessment in light of certain criteria – in particular, eligibility criteria (a subject's properties that make the subject principally eligible for moral assessments) and assignment criteria (particulars about the subject, act, and circumstances that justify assessments such as blame in a particular case). Strawson's analysis of the ordinary attitudes and practices of moral assessment hints at these criteria but does not unequivocally ground a notion of desert. Following Strawson's general naturalistic approach, we show that recent psychological research on folk concepts and practices regarding freedom, moral responsibility, and blame illuminates how people actually arrive at moral assessments, thus revealing the very eligibility criteria and assignment criteria we suggest ground a concept of desert. By pushing the Strawsonian line even further than Strawson did, by empirically investigating actual moral practice and folk understandings, we can illuminate desert and lend credence to Strawson's general anti-metaphysical position.

Considering the close relation between language and theory of mind in development and their tight connection in social behavior, it is no big leap to claim that the two capacities have been related in evolution as well. But what is the exact relation between them? This paper attempts to clear a path toward an answer. I consider several possible relations between the two faculties, bring conceptual arguments and empirical evidence to bear on them, and end up arguing for a version of co-evolution. To model this co-evolution, we must distinguish between different stages or levels of language and theory of mind, which fueled each other’s evolution in a protracted escalation process.

Extant models of moral judgment assume that an action’s intentionality precedes assignments of blame. Knobe (2003b) challenged this fundamental order and proposed instead that the badness or blameworthiness of an action directs (and thus unduly biases) people’s intentionality judgments. His and other researchers’ studies suggested that blameworthy actions are considered intentional even when the agent lacks skill (e.g., killing somebody with a lucky shot) whereas equivalent neutral actions are not (e.g., luckily hitting a bull’s-eye). The present five studies offer an alternative account of these provocative findings. We suggest that people see the morally significant action examined in previous studies (killing) as accomplished by a basic action (pressing the trigger) for which an unskilled agent still has sufficient skill. Studies 1 through 3 show that when this basic action is performed unskillfully or is absent, people are far less likely to view the killing as intentional, demonstrating that intentionality judgments, even about immoral actions, are guided by skill information. Studies 4 and 5 further show that a neutral action such as hitting the bull’s-eye is more difficult than killing and that difficult actions are less often judged intentional. When difficulty is held constant, people’s intentionality judgments are fully responsive to skill information regardless of moral valence. The present studies thus speak against the hypothesis of a moral evaluation bias in intentionality judgments and instead document people’s sensitivity to subtle features of human action.

Attribution theory has played a major role in social-psychological research. Unfortunately, the term attribution is ambiguous. According to one meaning, forming an attribution is making a dispositional (trait) inference from behavior; according to another meaning, forming an attribution is giving an explanation (especially of behavior). The focus of this paper is on the latter phenomenon of behavior explanations. In particular, I discuss a new theory of explanation that provides an alternative to classic attribution theory as it dominates the textbooks and handbooks—which is typically as a version of Kelley’s (1967) model of attribution as covariation detection. I begin with a brief critique of this theory and, out of this critique, develop a list of requirements that an improved theory has to meet. I then introduce the new theory, report empirical data in its support, and apply it to a number of psychological phenomena. I finally conclude with an assessment of how much progress we have made in understanding behavior explanations and what has yet to be learned.

The human ability to represent, conceptualize, and reason about mind and behavior is one of the greatest achievements of human evolution and is made possible by a “folk theory of mind” — a sophisticated conceptual framework that relates different mental states to each other and connects them to behavior. This chapter examines the nature and elements of this framework and its central functions for social cognition. As a conceptual framework, the folk theory of mind operates prior to any particular conscious or unconscious cognition and provides the “framing” or interpretation of that cognition. Central to this framing is the concept of intentionality, which distinguishes intentional action (caused by the agent’s intention and decision) from unintentional behavior (caused by internal or external events without the intervention of the agent’s decision). A second important distinction separates publicly observable from publicly unobservable (i.e., mental) events. Together, the two distinctions define the kinds of events in social interaction that people attend to, wonder about, and try to explain. A special focus of this chapter is the powerful tool of behavior explanation, which relies on the folk theory of mind but is also intimately tied to social demands and to the perceiver’s social goals. A full understanding of social cognition must consider the folk theory of mind as the conceptual underpinning of all (conscious and unconscious) perception and thinking about the social world