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.     

Applied Logic without Psychologism

Logic is a celebrated representation language because of its formal generality. But there are two senses in which a logic may be considered general, one that concerns a technical ability to discriminate between different types of individuals, and another that concerns constitutive norms for reasoning as such. This essay embraces the former, permutation-invariance conception of logic and rejects the latter, Fregean conception of logic. The question of how to apply logic under this pure invariantist view is addressed, and a methodology is given. The pure invariantist view is contrasted with logical pluralism, and a methodology for applied logic is demonstrated in remarks on a variety of issues concerning non-monotonic logic and non-monotonic inference, including Charles Morgan’s impossibility results for non-monotonic logic, David Makinson’s normative constraints for non-monotonic inference, and Igor Douven and Timothy Williamson’s proposed formal constraints on rational acceptance.     

Majority merging by adaptive counting

The present paper introduces a belief merging procedure by majority using the standard format of Adaptive Logics. The core structure of the logic ADM ^c (Adaptive Doxastic Merging by Counting) consists in the formulation of the conflicts arising from the belief bases of the agents involved in the procedure. A strategy is then defined both semantically and proof-theoretically which selects the consistent contents answering to a majority principle. The results obtained are proven to be equivalent to a standard majority operator for bases with partial support.     

Can an agent's false belief be corrected by an appropriate communication? Psychological reasoning in 18-month-old infants

Do 18-month-olds understand that an agent's false belief can be corrected by an appropriate, though not an inappropriate, communication? In Experiment 1, infants watched a series of events involving two agents, a ball, and two containers: a box and a cup. To start, agent1 played with the ball and then hid it in the box, while agent2 looked on. Next, in agent1's absence, agent2 moved the ball from the box to the cup. When agent1 returned, agent2 told her "The ball is in the cup!" (informative-intervention condition) or "I like the cup!" (uninformative-intervention condition). During test, agent1 reached for either the box (box event) or the cup (cup event). In the informative-intervention condition, infants who saw the box event looked reliably longer than those who saw the cup event; in the uninformative-intervention condition, the reverse pattern was found. These results suggest that infants expected agent1's false belief about the ball's location to be corrected when she was told "The ball is in the cup!", but not "I like the cup!". In Experiment 2, agent2 simply pointed to the ball's new location, and infants again expected agent1's false belief to be corrected. These and control results provide additional evidence that infants in the second year of life can attribute false beliefs to agents. In addition, the results suggest that by 18 months of age infants expect agents' false beliefs to be corrected by relevant communications involving words or gestures.     

The duty to believe according to the evidence

‘Evidentialism’ is the conventional name (given mainly by its opponents) for the view that there is a moral duty to proportion one’s beliefs to evidence, proof or other epistemic justifications for belief. This essay defends evidentialism against objections based on the alleged involuntariness of belief, on the claim that evidentialism assumes a doubtful epistemology, that epistemically unsupported beliefs can be beneficial, that there are significant classes of exceptions to the evidentialist principle, and other shabby evasions and alibis (as I take them to be) for disregarding the duty to believe according to the evidence. Evidentialism is also supported by arguments based on both self-regarding and other-regarding considerations.     

Choosing to believe

This article defends a regulative ethics of voluntary belief. In order to determine the occasion and the scope of such an ethics, the article begins with an examination of the concept of belief in conversation with the view of J. L. Schellenberg. Next, against the dominant position in contemporary epistemology, it argues that some beliefs can be voluntary, in the sense that they are under the immediate control of the believer, and replies to William Alston’s influential objections to doxastic voluntarism. If some beliefs are subject to the immediate control of the believer, then in these cases believers are ethically responsible not only for how they investigate those beliefs, but also for the choice of whether or not to believe them. The article concludes by formulating and defending two types of regulative ethical principles governing voluntary belief.     

Sleeping beauty and the dynamics of de se beliefs

This paper examines three accounts of the sleeping beauty case: an account proposed by Adam Elga, an account proposed by David Lewis, and a third account defended in this paper. It provides two reasons for preferring the third account. First, this account does a good job of capturing the temporal continuity of our beliefs, while the accounts favored by Elga and Lewis do not. Second, Elga’s and Lewis’ treatments of the sleeping beauty case lead to highly counterintuitive consequences. The proposed account also leads to counterintuitive consequences, but they’re not as bad as those of Elga’s account, and no worse than those of Lewis’ account.

Belief, assertion and Moore’s Paradox

In this article I argue that two received accounts of belief and assertion cannot both be correct, because they entail mutually contradictory claims about Moore’s Paradox. The two accounts in question are, first, the Action Theory of Belief (ATB), the functionalist view that belief must be manifested in dispositions to act, and second, the Belief Account of Assertion (BAA), the Gricean view that an asserter must present himself as believing what he asserts. It is generally accepted also that Moorean assertions are absurd, and that BAA explains why they are. I shall argue that ATB implies that some Moorean assertions are, in some fairly ordinary contexts, well justified. Thus BAA and ATB are mutually inconsistent. In the concluding section I explore three possible ways of responding to the dilemma, and what implications they have for the nature of the constitutive relationships linking belief, assent and behavioural dispositions.

When Effort is Threatening: The Influence of the Belief in a Just World on Americans' Attitudes Toward Antipoverty Policy

In the political context of the reauthorization of federal welfare reform legislation, a nationally representative sample of 1,570 adults in the United States completed a survey examining the factors that affect attitudes and policy preferences with regard to aid for low-income individuals and families in the United States. This study utilized an innovative survey technique, the factorial survey methodology (Rossi & Nock, 1982), which allows for the simultaneous experimental manipulation of a large number of factors through the use of a vignette. This research demonstrates how the portrayal of difficulties faced by people in need and the ways in which they attempt to overcome these difficulties affect support for policies designed to aid low-income individuals and families. In addition, this study of public attitudes considers the role that psychological orientations of the evaluators play in judgments of families in need. In this case, we examined how the evaluators' belief that the world is a just place influences their evaluations of deservingness. Consistent with our expectations, we found that the more efforts the vignette subject engaged in improving her situation, the less deserving of government benefits she was judged to be by respondents with a strong belief in a just world. The reverse was found among respondents with a weaker belief: more efforts were associated with greater judgments of deservingness.     

The Product of Self-Deception

I raise the question of what cognitive attitude self-deception brings about. That is: what is the product of self-deception? Robert Audi and Georges Rey have argued that self-deception does not bring about belief in the usual sense, but rather “avowal” or “avowed belief.” That means a tendency to affirm verbally (both privately and publicly) that lacks normal belief-like connections to non-verbal actions. I contest their view by discussing cases in which the product of self-deception is implicated in action in a way that exemplifies the motivational role of belief. Furthermore, by applying independent criteria of what it is for a mental state to be a belief, I defend the more intuitive view that being self-deceived that p entails believing that p. Beliefs (i) are the default for action relative to other cognitive attitudes (such as imagining and hypothesis) and (ii) have cognitive governance over the other cognitive attitudes. I explicate these two relations and argue that they obtain for the product of self-deception.