Towards a theory of intention revision

Although the change of beliefs in the face of new information has been widely studied with some success, the revision of other mental states has received little attention from the theoretical perspective. In particular, intentions are widely recognised as being a key attitude for rational agents, and while several formal theories of intention have been proposed in the literature, the logic of intention revision has been hardly considered. There are several reasons for this: perhaps most importantly, intentions are very closely connected with other mental states—in particular, beliefs about the future and the abilities of the agent. So, we cannot study them in isolation. We must consider the interplay between intention revision and the revision of other mental states, which complicates the picture considerably. In this paper, we present some first steps towards a theory of intention revision. We develop a simple model of an agent’s mental states, and define intention revision operators. Using this model, we develop a logic of intention dynamics, and then investigate some of its properties.     

How to think about the Modularity of Mind-Reading

It has been suggested that the fixation of beliefs about people's beliefs, desires and intentions is modularized. We argue that this is unlikely. We argue that there is modularity lower down: social-intentional 'markers' are produced by an encapsulated mechanism intermediate between perception and belief-fixation, and that these markers make a distinctive contribution to the fixation of beliefs about the mental. But belief fixation itself is not modular. Finally, we suggest some complications to our simple picture, and some ways in which our thesis might shed light on pathologies of social understanding.     

儿童早期心理洞察力的发展─—关于儿童社会认知的又一个研究方向

关于儿童心理洞察力发展的研究开始于８０年代初期,心理学家将个体认识自己和他人心理状态的系统性知识结构统称为个体的“心态理论”（ｔｈｅｏｒｙｏｆｍｉｎｄ）模式。在这个模式中包含着人的各种社会心理因素,如思想、信念、愿望、意图、情感等,各因素间里逻辑性联系,该模式为人的行为提供一种因果性解释机制。“心态理论”模式的发展对儿童社会认知、适应性行为以及元认知等方面的发展都具有重要促进作用。该研究涉及许多具体方面,本文主要提及下述几方面的研究：儿童早期对情绪的理解、儿童早期对伪误言行的理解以及儿童孤独症的表现等。大部分研究发现,３—４岁是儿童早期心理洞察力发展的重要年龄。     

A temporal modelling environment for internally grounded beliefs,desires and intentions

In this paper the internal dynamics of mental states, in particular states based on beliefs, desires and intentions, is formalised using a temporal language. A software environment is presented that can be used to specify, simulate and analyse temporal dependencies between mental states in relation to traces of them. If also relevant data on internal physical states over time are available, these can be analysed with respect to their relation to mental states as well.     

When Mental States Matter,When They Don't,and What That Means for Morality

Research has shown that moral judgments depend on the capacity to engage in mental state reasoning. In this article, we will first review behavioral and neural evidence for the role of mental states (e.g., people's beliefs, desires, intentions) in judgments of right and wrong. Second, we will consider cases where mental states appear at first to matter less (i.e., when people assign moral blame for accidents and when explicit information about mental states is missing). Third, we will consider cases where mental states, in fact, matter less, specifically, in cases of “purity” violations (e.g., committing incest, consuming taboo foods). We will discuss how and why mental states do not matter equivalently across the multi‐dimensional space of morality. In the fourth section of this article, we will elaborate on the possibility that norms against harmful actions and norms against “impure” actions serve distinct functions – for regulating interpersonal interactions (i.e., harm) versus for protecting the self (i.e., purity). In the fifth and final section, we will speculate on possible differences in how we represent and reason about other people's mental states versus our own beliefs and intentions. In addressing these issues, we aim to provide insight into the complex structure and distinct functions of mental state reasoning and moral cognition. We conclude that mental state reasoning allows us to make sense of other moral agents in order to understand their past actions, to predict their future behavior, and to evaluate them as potential friends or foes.     

Action understanding as inverse planning

Humans are adept at inferring the mental states underlying other agents’ actions, such as goals, beliefs, desires, emotions and other thoughts. We propose a computational framework based on Bayesian inverse planning for modeling human action understanding. The framework represents an intuitive theory of intentional agents’ behavior based on the principle of rationality: the expectation that agents will plan approximately rationally to achieve their goals, given their beliefs about the world. The mental states that caused an agent’s behavior are inferred by inverting this model of rational planning using Bayesian inference, integrating the likelihood of the observed actions with the prior over mental states. This approach formalizes in precise probabilistic terms the essence of previous qualitative approaches to action understanding based on an “intentional stance” [Dennett, D. C. (1987). The intentional stance. Cambridge, MA: MIT Press] or a “teleological stance” [Gergely, G., Nádasdy, Z., Csibra, G., & Biró, S. (1995). Taking the intentional stance at 12 months of age. Cognition, 56, 165-193]. In three psychophysical experiments using animated stimuli of agents moving in simple mazes, we assess how well different inverse planning models based on different goal priors can predict human goal inferences. The results provide quantitative evidence for an approximately rational inference mechanism in human goal inference within our simplified stimulus paradigm, and for the flexible nature of goal representations that human observers can adopt. We discuss the implications of our experimental results for human action understanding in real-world contexts, and suggest how our framework might be extended to capture other kinds of mental state inferences, such as inferences about beliefs, or inferring whether an entity is an intentional agent.     

Levels of modality for BDI Logic

The use of rational agents for modelling real world problems has both been heavily investigated and become well accepted, with BDI (Beliefs, Desires, and Intentions) Logic being a widely used architecture to represent and reason about rational agency. However, in the real world, we often have to deal with different levels of confidence in the beliefs we hold, desires we have, and intentions that we commit to. This paper extends our previous framework that integrated qualitative levels of beliefs, desires, and intentions into BDI Logic. We describe an expanded set of axioms and properties of the extended logic. We present a modular structure for the semantics which involves a non-normal Kripke type semantics that may be used for other agent systems. Further, we demonstrate the usefulness of our framework with a scheduling task example.     

Is belief reasoning automatic?

Understanding the operating characteristics of theory of mind is essential for understanding how beliefs, desires, and other mental states are inferred, and for understanding the role such inferences could play in other cognitive processes. We present the first investigation of the automaticity of belief reasoning. In an incidental false-belief task, adult subjects responded more slowly to unexpected questions concerning another person's belief about an object's location than to questions concerning the object's real location. Results in other conditions showed that responses to belief questions were not necessarily slower than responses to reality questions, as subjects showed no difference in response times to belief and reality questions when they were instructed to track the person's beliefs about the object's location. The results suggest that adults do not ascribe beliefs to agents automatically.     

Conversation and Behavior Games in the Pragmatics of Dialogue

In this article we present the bases for a computational theory of the cognitive processes underlying human communication. The core of the article is devoted to the analysis of the phases in which the process of comprehension of a communicative act can be logically divided: (1) literal meaning, where the reconstruction of the mental states literally expressed by the actor takes place: (2) speaker's meaning, where the partner reconstructs the communicative intentions of the actor; (3) communicative effect, where the partner possibly modifies his own beliefs and intentions; (4) reaction, where the intentions for the generation of the response are produced; and (5) response, where an overt response is constructed. The model appears to be compatible with relevant facts about human behavior. Our hypothesis is that, through communication, an actor tries to exploit the motivational structures of a partner so that the desired goal is generated. A second point is that social behavior requires that cooperation be maintained at some level. In the case of communication, cooperation is, in general, pursued even when the partner does not adhere to the actor's goals, and therefore no cooperation occurs at the behavioral level. This important distinction is reflected in the two kinds of game we introduce to account for communication. The main concept implied in communication is that two agents overtly reach a situation of shared mental states. Our model deals with sharedness through two primitives: shared beliefs and communicative intentions.     

Neural correlates of theory-of-mind reasoning: an event-related potential study

Everyday understanding of human behavior rests on having a theory of mind—the ability to relate people's actions to underlying mental states such as beliefs and desires. It has been suggested that an impaired theory of mind may lie at the heart of psychological disorders that are characterized by deficits in social understanding, such as autism. In this study, we employed the event-related potential methodology to index the activity of neural systems that are engaged during theory-of-mind reasoning in adults. Specifically, neural activity elicited by tasks that required thinking about mental as compared with nonmental representations (i.e., beliefs vs. photographs) was characterized by a focally enhanced positivity over left frontal areas, which was diminished over left parietal areas. These findings provide an important perspective on both children's theory-of-mind development and the neurobiology of disorders in which theory of mind seems to be impaired.     

Neural correlates of belief- and desire-reasoning in 7- and 8-year-old children: an event-related potential study

Theory of mind requires belief‐ and desire‐understanding. Event‐related brain potential (ERP) research on belief‐ and desire‐reasoning in adults found mid‐frontal activations for both desires and beliefs, and selective right‐posterior activations only for beliefs. Developmentally, children understand desires before beliefs; thus, a critical question concerns whether neural specialization for belief‐reasoning exists in childhood or develops later. Neural activity was recorded as 7‐ and 8‐year‐olds (N = 18) performed the same diverse‐desires, diverse‐beliefs, and physical control tasks used in a previous adult ERP study. Like adults, mid‐frontal scalp activations were found for belief‐ and desire‐reasoning. Moreover, analyses using correct trials alone yielded selective right‐posterior activations for belief‐reasoning. Results suggest developmental links between increasingly accurate understanding of complex mental states and neural specialization supporting this understanding.     

Stereotyped beliefs about desirability: implications for characterizing the child's theory of mind

A central research issue in the child's theory of mind literature is the question of whether children appreciate the subjectivity of mental phenomena. The typical research paradigm involves researchers creating a discrepancy between children's own mental states and the mental state of a protagonist, and then asking children to predict the protagonist's reaction. A prediction that fits the child's own mental state (rather than the beliefs and desires of the protagonist) is seen as an indication that the child fails to acknowledge the subjectivity of mental phenomena.Here we present two experiments involving the use of desire statements in predicting other people's emotions which demonstrate that even when one does acknowledge the subjectivity of mental states, this does not necessarily leads to ‘correct’ predictions (e.g. predictions based on the protagonist's desires). Other factors, such as cultural knowledge, might influence this process. The first experiment demonstrates that even adults, with a fully operational theory of mind, sometimes choose to disregard information about other people's desires. Their own generalized beliefs about desirability appear to be instrumental in this respect. The second experiment, on sex-stereotyped preferences for toys, demonstrates that even young children already can use generalized beliefs about desirability as a basis for their predictions of others’ emotions, even when these beliefs on desirability do not coincide with their own desires. This strategy results in a response pattern that can be easily misconceived as an indication that the child does not yet appreciate the subjectivity of desires.Two remarks are made on the basis of these experiments. First, even a so-called ‘adult’ theory of mind tends to be affected by normative considerations and is therefore more complex than straightforward desire-belief reasoning. Second, whenever normative considerations come into play, researchers should be cautious that ‘correct’ answers in theory of mind testing may not always have been based on theory of mind reasoning, and that ‘incorrect’ answers do not necessarily imply the absence of an active theory of mind.     

Do chimpanzees seek explanations? Preliminary comparative investigations.

During the past decade, considerable effort has been devoted to understanding whether chimpanzees reason about unobservable variables as explanations for observable events. With respect to physical causality, these investigations have explored chimpanzees' understanding of gravity, force, mass, shape, and so on. With respect to social causality, this research has focused on the question of whether they reason about mental states such as emotions, desires, and beliefs. In the studies reported here, we explored whether the chimpanzee's natural motivation for object exploration is modulated by a cognitive system that seeks explanations for unexpected events. We confronted both chimpanzees and young children with simple tasks which occasionally could not be made to work. We coded their reactions to determine if they appeared to be searching for an apparent cause (or explanation) of the task failure. The results of these preliminary studies point to both similarities and differences in how young children and chimpanzees react to such circumstances.     

The effects of stimulating the cerebellum on social sequences: A tDCS-fMRI pilot study

Research on the involvement of the cerebellum in social behavior and its relationship with social mentalizing has just begun. Social mentalizing is the ability to attribute mental states such as desires, intentions, and beliefs to others. This ability involves the use of social action sequences which are believed to be stored in the cerebellum. In order to better understand the neurobiology of social mentalizing, we applied cerebellar transcranial direct current stimulation (tDCS) on 23 healthy participants in the MRI scanner, immediately followed by measuring their brain activity during a task that required to generate the correct sequence of social actions involving false (i.e., outdated) and true beliefs, social routines and non-social (control) events. The results revealed that stimulation decreased task performance along with decreased brain activation in mentalizing areas, including the temporoparietal junction and the precuneus. This decrease was strongest for true belief sequences compared to the other sequences. These findings support the functional impact of the cerebellum on the mentalizing network and belief mentalizing, contributing to the understanding of the role of the cerebellum in social sequences.     

Young children's understanding of desire formation

Two studies examined preschoolers' appreciation of how mental states arise. In Study 1, children aged 3 to 5 (24 at each age) better understood perception-generated beliefs (e.g., that looking in a certain location generates a belief about the location's content) and attitude-generated desires (e.g., that positive experiences with an activity generate a desire to partake of the activity again) than physiology-generated desires (e.g., that not eating for a long time generates a desire for food). In Study 2, 4- and 5-year-olds (48 at each age) better understood the effects of quantity of experience (e.g., eating a lot vs. a little) than of time of experience (eating just now vs. a long time ago) on physiological states and desires. The findings suggest that whether children reason in more advanced fashion about desires or beliefs depends on which aspects of these mental states are considered.     

Understanding cognitive,affective, and intimacy deficits in sexual offenders: A developmental perspective

Factors, such as intimacy deficits, problems empathizing with victims, and cognitive distortions, have all been associated with the genesis of sexual abuse. Importantly, they all point to a lack of awareness of other peoples' beliefs, desires, perspectives, and needs. We argue that sexual offenders' problems in these domains can be viewed as partially arising from deficits in one central mechanism: the ability to infer mental states. Following a review of the above three areas, we discuss the developmental literature on children's theory of mind and develop a model informed by this work. We apply this model to sexual offenders and discuss its research and clinical implications.     

The very idea of a folk Psychology.

Three arguments are proposed against the idea that ordinary talk about the mind constitutes a folk psychology, a sort of prescientific theory which explains human behaviour and which is ripe for replacement by a neurological or computational theory with better scientific credentials. First, not all talk of the mind is introduced to explain in the way assumed by those who think that mental talk hypothesizes inner processes to explain behaviour. Second, the individuation of the behaviour which is explained by the inner processes itself requires reference to ‘mental’ states such as intentions or desires. Consequently the project is circular. Finally, scientific theory is a practice with a history which may be matched in the case of ordinary talk of the mind. Certainly ordinary talk of motives, intentions, and thoughts may be infected by the theorizing of economists and sociologists et al., but it is impossible that all talk of the mind should be theoretical in this way.     

Alexithymia increases moral acceptability of accidental harms

Previous research shows that when people judge moral acceptability of others' harmful behaviour, they not only take into account information about the consequences of the act but also an actor's belief while carrying out the act. A two-process model has been proposed to account for this pattern of moral judgements and posits: (1) a causal process that detects the presence of a harmful outcome and is motivated by empathic aversion stemming from victim suffering; (2) a mental state-based process that attributes beliefs, desires, intentions, etc. to the agent in question and is motivated by imagining personally carrying out harmful actions. One prediction of this model would be that personality traits associated with empathy deficits would find accidental harms more acceptable not because they focus on innocent intentions but because they have reduced concern for the victim's well-being. In this study, we show that one such personality trait, viz. alexithymia, indeed exhibits the predicted pattern and this increased acceptability of accidental harm in alexithymia is mediated by reduced dispositional empathic concern. Results attest to the validity of two-process model of intent-based moral judgements and emphasise key role affective empathy plays in harm-based moral judgements.     

How to share a mind: Reconsidering the group mind thesis

Standard accounts in social ontology and the group cognition debate have typically focused on how collective modes, types, and contents of intentions or representational states must be construed so as to constitute the jointness of the respective agents, cognizers, and their engagements. However, if we take intentions, beliefs, or mental representations all to instantiate some mental properties, then the more basic issue regarding such collective engagements is what it is for groups of individual minds to share a mind. Somewhat surprisingly, this very issue has not received much attention in the respective debates and when it has, typically the outlook has been skeptical or outright negative. In this paper, I argue that it is epistemologically possible for a group of individuals to literally share a single mental unit. In particular, I will put forward and defend what I shall call the zombie conception of group minds.