The Fluent Calculus belongs to the established predicate calculus formalisms for reasoning about actions. Its underlying concept of state update axioms provides a solution to the basic representational and inferential Frame Problems in pure first-order logic. Extending a recent research result, we present a Fluent Calculus to reason about domains involving continuous change and where actions occur concurrently.

The present introduction to the Fluent Calculus is intended as an ETAI reference article. It summarizes basic definitions and concepts in the Fluent Calculus, and is intended as a reference for future articles where the calculus is used.

As a contribution to the challenge of building game-playing AI systems, we develop and analyse a formal language for representing and reasoning about strategies. Our logical language builds on the existing general Game Description Language and extends it by a standard modality for linear time along with two dual connectives to express preferences when combining strategies. The semantics of the language is provided by a standard state-transition model. As such, problems that require reasoning about games can be solved by the (...) standard methods for reasoning about actions and change. We also endow the language with a specific semantics by which strategy formulas are understood as move recommendations for a player. To illustrate how our formalism supports automated reasoning about strategies, we demonstrate two example methods of implementation: first, we formalise the semantic interpretation of our language in conjunction with game rules and strategy rules in the Situation Calculus; second, we show how the reasoning problem can be solved with Answer Set Programming. (shrink)

A logic-based approach to the design of computing systems would, undoubtedly, offer many advantages over the imperative paradigm most commonly applied so far for programming and hardware design and, consequently, logic, again and again, has been heralded as the basis for the next generation of computer systems. While logic and formal methods are indeed gaining ground in many areas of computer science and artificial intelligence the expected revolution has not yet happened. In this book the author offers a convincing solution (...) to the ramification problem and qualification problem associated with the frame problem and thus contributes to a satisfactory solution of the core problem and related challenges. Thielscher bases his approach on the fluent calculus, a first-order Prolog-like formalism allowing for the description of actions and change. (shrink)

As an extension of the well-known Action Description Language A introduced by M. Gelfond and V. Lifschitz [8] C. Baral and M. Gelfond recently defined the diafect AC which supports the description of concurrent actions [1]. Also, a sound but incomplete encoding of AC by means of an extended logic program was presented there. In this paper, we work on interpretations of contradictory inferences from partial action descriptions. Employing an interpretation different from the one implicitly used in AC, we present (...) a new dialect which allows to infer sound information from contradictory descriptions and to describe non-determinism and uncertainty. Furthermore, we give the first sound and complete encoding of AC, using equational logic programming, and extend it to as well. (shrink)

A general game player automatically learns to play arbitrary new games solely by being told their rules. For this purpose games are specified in the general Game Description Language (GDL), a variant of Datalog with function symbols that uses a few game-specific keywords. A recent extension of basic GDL allows the description of nondeterministic games with any number of players who may have incomplete, asymmetric information. In this paper, we analyse the epistemic structure and expressiveness of this language in terms (...) of modal epistemic logic and prove two main results: (1) The operational semantics of GDL entails that the situation at any stage of a game can be characterised by a multi-agent epistemic (i.e., S5-) model; (2) GDL is sufficiently expressive to model any situation that can be described by a (finite) multi-agent epistemic model. (shrink)

This book defends a form of ethical intuitionism, according to which (i) there are objective moral truths; (ii) we know some of these truths through a kind of immediate, intellectual awareness, or "intuition"; and (iii) our knowledge of moral truths gives us reasons for action independent of our desires. The author rebuts all the major objections to this theory and shows that the alternative theories about the nature of ethics all face grave difficulties.

The first edition of The Scientific Background to Modern Philosophy took the dialogue of science and philosophy from Aristotle through to Newton. This second edition adds eight chapters, taking the dialogue through the Enlightenment and up to Darwin. This anthology is an attempt to help bridge the gap between the history of science and the history of philosophy.

Part I: The representation of life -- Can life be given a real definition? -- The representation of the living individual -- The representation of the life-form itself -- Part II: Naive action theory -- Types of practical explanation -- Naive explanation of action -- Action and time -- Part III: Practical generality -- Two tendencies in practical philosophy -- Practices and dispositions as sources of the goodness of individual actions -- Practice and disposition as sources of individual action.

Virtually all philosophers agree that for a belief to be epistemically justified, it must satisfy certain conditions. Perhaps it must be supported by evidence. Or perhaps it must be reliably formed. Or perhaps there are some other "good-making" features it must have. But does a belief's justification also require some sort of awareness of its good-making features? The answer to this question has been hotly contested in contemporary epistemology, creating a deep divide among its practitioners. Internalists, who tend to focus (...) on scientific or theoretical beliefs as the ideal, insist that such awareness is required for justification. Externalists, who think children's ordinary beliefs in obvious facts are paradigm cases of justified belief, say it isn't required. Michael Bergmann's book offers a decisive refutation of internalism and a sustained defense of externalism. (shrink)

Externalist theories of justification create the possibility of cases in which everything appears to one relevantly similar with respect to two propositions, yet one proposition is justified while the other is not. Internalists find this difficult to accept, because it seems irrational in such a case to affirm one proposition and not the other. The underlying internalist intuition supports a specific internalist theory, Phenomenal Conservatism, on which epistemic justification is conferred by appearances.

At the University of Sheffield during 2011 and 2012, a leading group of philosophers, psychologists, and others gathered to explore the nature and significance of implicit bias. The two volumes of Implicit Bias and Philosophy emerge from these workshops. Each volume philosophically examines core areas of psychological research on implicit bias as well as the ramifications of implicit bias for core areas of philosophy. Volume I: Metaphysics and Epistemology is comprised of two parts: “The Nature of Implicit Attitudes, Implicit Bias, (...) and Stereotype Threat,” and “Skepticism, Social Knowledge, and Rationality.” The first part contains chapters examining the relationship between implicit attitudes and “dual process” models of the mind; the role of affect in the formation and change of implicit associations; the unity (or disunity) of implicit attitudes; whether implicit biases are mental states at all; and whether performances on stereotype-relevant tasks are automatic and unconscious or intentional and strategic. The second part contains chapters examining implicit bias and skepticism; the effects of implicit bias on scientific research; the accessibility of social stereotypes in epistemic environments; the effects of implicit bias on the self-perception of members of stigmatized social groups as rational agents; the role of gender stereotypes in philosophy; and the role of heuristics in biased reasoning. (shrink)

In this engaging and spirited text, Michael Lynch argues that truth does matter, in both our personal and political lives. He explains that the growing cynicism over truth stems in large part from our confusion over what truth is.

Dignity plays a central role in current thinking about law and human rights, but there is sharp disagreement about its meaning. Combining conceptual precision with a broad historical background, Michael Rosen puts these controversies in context and offers a novel, constructive proposal. “Penetrating and sprightly...Rosen rightly emphasizes the centrality of Catholicism in the modern history of human dignity. His command of the history is impressive...Rosen is a wonderful guide to the recent German constitutional thinking about human dignity...[Rosen] is in (...) general an urbane and witty companion, achieving his aim of accessibly written philosophy.” —Samuel Moyn, The Nation “[An] elegant, interesting and lucid exploration of the concept of dignity...Drawing on classical, liberal and Catholic traditions, Rosen hopes to rehabilitate dignity to its rightful place near the centre of moral thought...Rosen's admirable book deserves wide attention from political theorists, jurisprudes and political philosophers.” —Simon Blackburn, Times Higher Education “Dignity deserves to be widely read, not only for its intrinsic interest, but also as a corrective to the habit of discussing such topics in abstraction from their social context. Whether or not one agrees with Rosen's arguments, there can be no doubt he has widened our horizons.” —Rae Langton, Times Literary Supplement. (shrink)

The article of Dr. Wasserstein, ‘The Manuscript-tradition of Statius'; Siluae’, C.Q. N.s. iii , 69–78, causes me to revert once again to the question I treated twice in Philologus Ixvi , 85–134; lxxxii , 167–180. In the first place I must refer to a frequent slip of the pen which occurs, for example, in the 414 verses of the Culex thrice, viz.

Michael G. Titelbaum presents a new Bayesian framework for modeling rational degrees of belief—the first of its kind to represent rational requirements on agents who undergo certainty loss.

edition (unseen), $12.95. traditions, bringing into being new modes of understanding. Paper Anthropology, and particularly ethnography, is torn between two quests, one to capture the diversity of social life and the other to discover universal principles structuring that diversity. Jackson examines these quests within the context of ethnographic fieldwork, focusing on the relationship between ethnographers and the people they study. He is concerned with defining the anthropological project as something more than the projection of the anthropologist's traditions and concerns onto (...) an alien culture. Rather, he would have the project open a genuine dialogue between people from different cultures or Annotation copyrighted by Book News, Inc., Portland, OR. (shrink)

At the heart of ethics reside the concepts of good and bad; they are at work when we assess whether a person is virtuous or vicious, an act right or wrong, a decision defensible or indefensible, a goal desirable or undesirable. But there are many varieties of goodness and badness. At their core lie intrinsic goodness and badness, the sort of value that something has for its own sake. It is in virtue of intrinsic value that other types of value (...) may be understood, and hence that we can begin to come to terms with questions of virtue and vice, right and wrong, and so on. This book investigates the nature of intrinsic value: just what it is for something to be valuable for its own sake, just what sort of thing can have such value, just how such a value is to be computed. In the final chapter, the fruits of this investigation are applied to a discussion of pleasure, pain, and displeasure and also of moral virtue and vice, in order to determine just what value lies within these phenomena. (shrink)

While philosophers hold that it is patently absurd to blame robots or hold them morally responsible [1], a series of recent empirical studies suggest that people do ascribe blame to AI systems and robots in certain contexts [2]. This is disconcerting: Blame might be shifted from the owners, users or designers of AI systems to the systems themselves, leading to the diminished accountability of the responsible human agents [3]. In this paper, we explore one of the potential underlying reasons for (...) robot blame, namely the folk's willingness to ascribe inculpating mental states or "mens rea" to robots. In a vignette-based experiment (N=513), we presented participants with a situation in which an agent knowingly runs the risk of bringing about substantial harm. We manipulated agent type (human v. group agent v. AI-driven robot) and outcome (neutral v. bad), and measured both moral judgment (wrongness of the action and blameworthiness of the agent) and mental states attributed to the agent (recklessness and the desire to inflict harm). We found that (i) judgments of wrongness and blame were relatively similar across agent types, possibly because (ii) attributions of mental states were, as suspected, similar across agent types. This raised the question - also explored in the experiment - whether people attribute knowledge and desire to robots in a merely metaphorical way (e.g., the robot "knew" rather than really knew). However, (iii), according to our data people were unwilling to downgrade to mens rea in a merely metaphorical sense when given the chance. Finally, (iv), we report a surprising and novel finding, which we call the inverse outcome effect on robot blame: People were less willing to blame artificial agents for bad outcomes than for neutral outcomes. This suggests that they are implicitly aware of the dangers of overattributing blame to robots when harm comes to pass, such as inappropriately letting the responsible human agent off the moral hook. (shrink)

In previous work I have argued against internalism by means of a dilemma intended to force all internalists to accept one of two undesirable options: either their internalism is unmotivated or it is saddled with vicious regress problems. Recently it has been argued that Phenomenal Conservatism—a theory of justification according to which justification depends on seemings—is a kind of internalism that can escape this dilemma. In this paper, I argue that Phenomenal Conservatism cannot escape my dilemma for internalism. In order (...) to do this, it is helpful to get clear on what Phenomenal Conservatism is saying, and for that reason I begin, in section I, by examining in some detail what seemings are. I then argue, in the remainder of the paper, that, whichever horn of the dilemma for internalism they take, Phenomenal Conservatives are in trouble. (shrink)

Can an ugly experiment be a good experiment? Philosophers have identified many beautiful experiments and explored ways in which their beauty might be connected to their epistemic value. In contrast, the present chapter seeks out (and celebrates) ugly experiments. Among the ugliest are those being designed by AI algorithms. Interestingly, in the contexts where such experiments tend to be deployed, low aesthetic value correlates with high epistemic value. In other words, ugly experiments can be good. Given this, we should conclude (...) that beauty is not generally necessary or sufficient for epistemic value, and increasing beauty will not generally tend to increase epistemic value. (shrink)

Radical skepticism endorses the extreme claim that large swaths of our ordinary beliefs, such as those produced by perception or memory, are irrational. The best arguments for such skepticism are, in their essentials, as familiar as a popular science fiction movie and yet even seasoned epistemologists continue to find them strangely seductive. Moreover, although most contemporary philosophers dismiss radical skepticism, they cannot agree on how best to respond to the challenge it presents. In the tradition of the 18th century Scottish (...) philosopher, Thomas Reid, Radical Skepticism and Epistemic Intuition joins this discussion by taking up four main tasks. First, it identifies the strongest arguments for radical skepticism, namely, underdetermination arguments, which emphasize the gap between our evidence and our ordinary beliefs based on that evidence. Second, it rejects all inferential or argument-based responses to radical skepticism, which aim to lay out good noncircular reasoning from the evidence on which we base our ordinary beliefs to the conclusion that those beliefs are probably true. Third, it develops a commonsense noninferential response to radical skepticism with two distinctive features: it consciously and extensively relies on epistemic intuitions, which are seemings about epistemic goods, such as knowledge and rationality, and it can be endorsed without difficulty by both internalists and externalists in epistemology. Fourth, and finally, it defends this commonsense epistemic-intuition-based response to radical skepticism against a variety of objections, including those connected with underdetermination worries, epistemic circularity, disagreement problems, experimental philosophy, and concerns about whether it engages skepticism in a sufficiently serious way. (shrink)

A paradigm-shifting work that revolutionizes our understanding of the origins and structure of science. Captivatingly written, interwoven with tantalizing illustrations and historical vignettes ranging from Newton's alchemy to quantum mechanics to the storm surge of Hurricane Sandy, Michael Strevens's wholly original investigation of science asks two fundamental questions: Why is science so powerful? And why did it take so long, two thousand years after the invention of philosophy and mathematics, for the human race to start using science to learn (...) the secrets of nature? The Knowledge Machine's radical answer is that science calls on its practitioners to do something irrational: by willfully ignoring religion, theoretical beauty, and, especially, philosophy-essentially stripping away all previous knowledge-scientists embrace an unnaturally narrow method of inquiry, channeling unprecedented energy into observation and experimentation. Like Yuval Harari's Sapiens or Thomas Kuhn's 1962 classic, The Structure of Scientific Revolutions, The Knowledge Machine overturns much of what we thought we knew about the origins of the modern world. (shrink)

Imagination is important for many things in science: solving problems, interpreting data, designing studies, etc. Philosophers of imagination typically account for the productive role played by imagination in science by focusing on how imagination is constrained, e.g., by using self-imposed rules to infer logically, or model events accurately. But the constraints offered by these philosophers either constrain too much, or not enough, and they can never account for uses of imagination that are needed to break today’s constraints in order to (...) make progress tomorrow. Thus, epistemology of imagination needs to make room for an element of epistemological anarchy. (shrink)