We investigate the notion of relevance as it pertains to ‘commonsense’, subjunctive conditionals. Relevance is taken here as a relation between a property (such as having a broken wing) and a conditional (such as birds typically fly). Specifically, we explore a notion of ‘causative’ relevance, distinct from ‘evidential’ relevance found, for example, in probabilistic approaches. A series of postulates characterising a minimal, parsimonious concept of relevance is developed. Along the way we argue that no purely logical account of relevance (even (...) at the metalevel) is possible. Finally, and with minimal restrictions, an explicit definition that agrees with the postulates is given. (shrink)

This paper describes an approach for reasoning in a dynamic domain with nondeterministic actions in which an agent’s beliefs correspond to the simplest, or most plausible, course of events consistent with the agent’s observations and beliefs. The account is based on an epistemic extension of the situation calculus, a first-order theory of reasoning about action that accommodates sensing actions. In particular, the account is based on a qualitative theory of nondeterminism. Our position is that for commonsense reasoning, the world is (...) most usefully regarded as deterministic, and that nondeterminism is an epistemic phenomenon, arising from an agent’s limited awareness and perception. The account offers several advantages: an agent has a set of categorical beliefs, yet can deal with equally-likely outcomes or with outcomes of differing plausibility. The agent maintains as its set of contingent beliefs the most plausible, or simplest, picture of the world, consistent with its beliefs and actions it believes it executed; yet it may modify these in light of later information. (shrink)

In this paper we explore a class of belief update operators, in which the definition of the operator is compositional with respect to the sentence to be added. The goal is to provide an update operator that is intuitive, in that its definition is based on a recursive decomposition of the update sentence’s structure, and that may be reasonably implemented. In addressing update, we first provide a definition phrased in terms of the models of a knowledge base. While this operator (...) satisfies a core group of the benchmark Katsuno Mendelzon update postulates, not all of the postulates are satisfied. Other Katsuno Mendelzon postulates can be obtained by suitably restricting the syntactic form of the sentence for update, as we show. In restricting the syntactic form of the sentence for update, we also obtain a hierarchy of update operators with Winslett’s standard semantics as the most basic interesting approach captured. We subsequently give an algorithm which captures this approach; in the general case the algorithm is exponential, but with some not unreasonable assumptions we obtain an algorithm that is linear in the size of the knowledge base. Hence the resulting approach has much better complexity characteristics than other operators in some situations. We also explore other compositional belief change operators: erasure is developed as a dual operator to update; we show that a forget operator is definable in terms of update; and we give a definition of the compositional revision operator. We obtain that compositional revision, under the most natural definition, yields the Satoh revision operator. (shrink)

One of the standard principles of rationality guiding traditional accounts of belief change is the principle of minimal change: a reasoner's belief corpus should be modified in a minimal fashion when assimilating new information. This rationality principle has stood belief change in good stead. However, it does not deal properly with all belief change scenarios. We introduce a novel account of belief change motivated by one of Grice's maxims of conversational implicature: the reasoner's belief corpus is modified in a minimal (...) fashion to assimilate exactly the new information. In this form of belief change, when the reasoner revises by new information p ∨ q their belief corpus is modified so that p∨q is believed but stronger propositions like p∧q are not, no matter what beliefs are in the reasoner's initial corpus. We term this conservative belief change since the revised belief corpus is a conservative extension of the original belief corpus given the new information. (shrink)

This special issue presents a selection of papers in Knowledge Representation in Artificial Intelligence , intended to illustrate the depth and breadth of current research in the area. It comes just over 25 years since a similar special issue of the Journal of Philosophical Logic appeared on the topic Philosophical Logic and Artificial Intelligence [15]. This latter special issue covered work addressing the use of logic, in one form or another, for representing and reasoning with knowledge. The papers of the (...) 1988 special issue give a good indication of major themes of research at the time: reasoning about belief and knowledge [5], tractable logical reasoning [10], nonmonotonicity [11], and reasoning about action [13]. These topics can be considered to be centrally in KR; the current issue then also serves to indicate how the field has broadened and evolved over the last 25 years.Traditionally the area of Knowledge Representation has been seen as “the field of study concerned w .. (shrink)

Consistency-based approaches in nonmonotonic reasoning may be expected to yield multiple sets of default conclusions for a given default theory. Reasoning about such extensions is carried out at the meta-level. In this paper, we show how such reasoning may be carried out at the object level for a large class of default theories. Essentially we show how one can translate a default theory Δ, obtaining a second Δ', such that Δ has a single extension that encodes every extension of _. (...) Moreover, our translated theory is only a constant factor larger than the original. We prove that our translation behaves correctly. In the approach we can now encode the notion of extension from within the framework of standard default logic. Hence one can encode notions such as skeptical and credulous conclusions, and can reason about such conclusions within a single extension. This result has some theoretical interest, in that it shows how multiple extensions of semi-monotonic default theories are encodable with manageable overhead in a single extension. (shrink)

The contributions to the Special Issue on Multiple Belief Change, Iterated Belief Change and Preference Aggregation are divided into three parts. Four contributions are grouped under the heading "multiple belief change" (Part I, with authors M. Falappa, E. Fermé, G. Kern-Isberner, P. Peppas, M. Reis, and G. Simari), five contributions under the heading "iterated belief change" (Part II, with authors G. Bonanno, S.O. Hansson, A. Nayak, M. Orgun, R. Ramachandran, H. Rott, and E. Weydert). These papers do not only pick (...) up the particular questions raised, but also extend and modify the framework of Alchourrón, Gärdenfors and Makinson. Part III deals with preference aggregation and consists of one contribution (by F. Herzberg and D. Eckert). (shrink)

Structural realism is considered by many realists and antirealists alike as the most defensible form of scientific realism. There are now many forms of structural realism and an extensive literature about them. There are interesting connections with debates in metaphysics, philosophy of physics and philosophy of mathematics. This entry is intended to be a comprehensive survey of the field.

Moral philosophy is the study of what morality is and what it requires of us. As Socrates said, it's about "how we ought to live"-and why. It would be helpful if we could begin with a simple, uncontroversial definition of what morality is. Unfortunately, we cannot. There are many rival theories, each expounding a different conception of what it means to live morally, and any definition that goes beyond Socrates's simple formula-tion is bound to offend at least one of them. (...) This should make us cautious, but it need not paralyze us. In this chapter, I will describe the "minimum conception" of morality. (shrink)

For this 1897 publication, the American philosopher William James brought together ten essays, some of which were originally talks given to Ivy League societies. Accessible to a broader audience, these non-technical essays illustrate the author's pragmatic approach to belief and morality, arguing for faith and action in spite of uncertainty. James thought his audiences suffered 'paralysis of their native capacity for faith' while awaiting scientific grounds for belief. His response consisted in an attitude of 'radical empiricism', which deals (...) practically rather than ideologically with real-world phenomena. When facing a 'momentous' decision about belief, he says, we both can and must choose the best hypothesis. The first four essays apply this principle to religious faith, and the rest explore the pragmatic approach to such topics as determinism, ethics and individual achievement. James developed his ideas further in The Varieties of Religious Experience and Pragmatism, both of which are reissued in this series. (shrink)

One of the most influential men of his time, philosopher, psychologist, educator, and author William James (1842-1910) helped lead the transition from a predominantly European-centered nineteenth-century philosophy to a new "pragmatic" American philosophy. Helping to pave the way was his seminal book Pragmatism (1907), in which he included a chapter on "Truth," an essay which provoked severe criticism. In response, he wrote the present work, an attempt to bring together all he had ever written on the theory of knowledge, (...) including an article on the function of cognition, later polemic and expository contributions, and some replies to previous criticism. The result was a full and definitive expression of the pragmatist "epistemology" from James' point of view. In the book, he urges the reader to "turn away from abstractions, verbal solutions, fixed principles, and pretended absolutes and look for concreteness and facts, action and power," arguing that "the ultimate test for us of what a truth means is the conduct it dictates or inspires." For students, scholars--anyone interested in William James or the history of American philosophical thought--this book offers an in-depth exposition of the influential ideas of one of the greatest American thinkers. Unabridged republication of the edition originally published by Longmans, Green and Co., New York and London, 1909. (shrink)

We have several intuitive paradigms of defeating evidence. For example, let E be the fact that Ernie tells me that the notorious pet Precious is a bird. This supports the premise F, that Precious can fly. However, Orna gives me *opposing* evidence. She says that Precious is a dog. Alternatively, defeating evidence might not oppose Ernie's testimony in that direct way. There might be other ways for it to weaken the support that Ernie's testimony gives me for believing F, without (...) the new evidence itself intuitively constituting reasons to believe one way or the other about Precious's flight ability. An example: Ursula tells me that Ernie has no idea what Precious's species is; he's just guessing. She may not herself want to or be in a position to weigh in about Precious's real species or flight ability. I call defeating evidence of this sort *undermining evidence. (shrink)

Two books bound together, from the religious period of one of the most renowned and representative thinkers. Written for laymen, thus easy to understand, it is penetrating and brilliant as well. Illuminations of age-old religious questions from a pragmatic perspective, written in a luminous style.

It is our job now - the job of this book - to influence and develop the unsettled discourse of human rights so as to complete the incomplete idea.

Noted psychologist and philosopher develops his own brand of pragmatism, based on theories of C. S. Peirce. Emphasis on "radical empiricism," versus the transcendental and rationalist tradition. One of the most important books in American philosophy. Note.

Consider the following facts about the average, philosophically untrained moral relativist: (1.1) The average moral relativist denies the existence of “absolute moral truths.” (1.2) The average moral relativist often expresses her commitment to moral relativism with slogans like ‘What’s true (or right) for you may not be what’s true (or right) for me’ or ‘What’s true (or right) for your culture may not be what’s true (or right) for my culture.’ (1.3) The average moral relativist endorses relativistic views of morality (...) without endorsing relativistic views about science or mathematics. (1.4) The average moral relativist takes moral relativism to be non-relatively true and does not think there is anything contradictory about doing so. (1.5) The average moral relativist adopts an egalitarian attitude toward a wide range of moral values, practices and beliefs, claiming they are all equally legitimate or correct. (1.6) The average moral relativist often admonishes others to be more tolerant of those who engage in alternative ethical practices and to refrain from making negative moral judgments about them. (1.7) The average moral relativist sometimes makes negative moral judgments about the behavior of others—e.g., by harshly judging moral absolutists to be intolerant—but is less inclined to do so when the relativist’s metaethical views are salient in a context of judgment. (1.8) The average moral relativist takes anthropological evidence concerning the worldwide diversity of ethical views and practices to support moral relativism. (shrink)

Experimental philosophy brings empirical methods to philosophy. These methods are used to probe how people think about philosophically interesting things such as knowledge, morality, and freedom. This paper explores the contribution that qualitative methods have to make in this enterprise. I argue that qualitative methods have the potential to make a much greater contribution than they have so far. Along the way, I acknowledge a few types of resistance that proponents of qualitative methods in experimental philosophy might encounter, and provide (...) reasons to think they are ill-founded. (shrink)

From the bestselling author of Assholes: A Theory, a book that--in the tradition of Shopclass as Soulcraft, Barbarian Days and Zen and the Art of Motorcycle Maintenance--uses the experience and the ethos of surfing to explore key concepts in philosophy. The existentialist philosopher Jean-Paul Sartre once declared "the ideal limit of aquatic sports...is waterskiing." The avid surfer and lavishly credentialed academic philosopher Aaron James vigorously disagrees, and in Surfing with Sartre he intends to expound the thinking surfer's view of (...) the matter, in the process elucidating such philosophical categories as freedom, being, phenomenology, morality, epistemology, and even the emerging values of what he terms "leisure capitalism." In developing his unique surfer-philosophical worldview, he draws from his own experience of surfing and from surf culture and lingo, and includes many relevant details from the lives of the philosophers, from Aristotle to Wittgenstein, with whose thought he engages. In the process, he'll speak to readers in search of personal and social meaning in our current anxious moment, by way of doing real, authentic philosophy. (shrink)

Louis Agassiz.--Address at the Emerson Centenary in Concord.--Robert Gould Shaw.--Francis Boott.--Thomas Davidson: a knight-errant of the intellectual life.--Herbert Spencer's autobiography.--Frederick Myers' services to psychology.--Final impressions of a psychical researcher.--On some mental effects of the earthquake.--The energies of men.--The moral equivalent of war.--Remarks at the peace banquet.--The social value of the college-bred.--The university and the individual: The Ph.D. octopus. The true Harvard. Stanford's ideal destiny.--A pluralistic mystic.

Recent empirical work on folk moral objectivism has attempted to examine the extent to which folk morality presumes that moral judgments are objectively true or false. Some researchers report findings that they take to indicate folk commitment to objectivism (Goodwin & Darley, 2008, 2010, 2012; Nichols & Folds-Bennett, 2003; Wainryb et al., 2004), while others report findings that may reveal a more variable commitment to objectivism (Beebe, 2014; Beebe et al., 2015; Beebe & Sackris, 2016; Sarkissian, et al., 2011; Wright, (...) 2018; Wright, Grandjean, & McWhite, 2013; Wright, McWhite, & Grandjean, 2014). However, the various probes that have been used to examine folk moral objectivism almost always fail to be good direct measures of objectivism. Some critics (Beebe, 2015; Pölzler, 2017, 2018) have suggested that the problems with existing probes are serious enough that they should be viewed as largely incapable of shedding any light on folk metaethical commitments. Building upon the work of Justin Khoo and Joshua Knobe (2018), I argue that many of the existing probes can be seen as good measures of the extent to which people think that the truth of one moral judgment excludes the possibility that a judgment made by a disagreeing party is also true and that the best explanation of the findings obtained using these measures is significant folk support for indexical moral relativism—the view that the content of moral judgments is context-sensitive. If my thesis is correct, many contemporary moral philosophers are deeply mistaken about the metaethical contours of folk morality in one very important respect. (shrink)

Yoga is hugely popular around the world today, yet until now little has been known of its roots. This book collects, for the first time, core teachings of yoga in their original form, translated and edited by two of the world's foremost scholars of the subject. It includes a wide range of texts from different schools of yoga, languages and eras: among others, key passages from the early Upanisads and the Mahabharata, and from the Tantric, Buddhist and Jaina traditions, with (...) many pieces in scholarly translation for the first time. Covering yoga's varying definitions across systems, models of the esoteric and physical bodies, and its most important practices, such as posture, breath control, sensory withdrawal and meditation, Roots of Yoga is a unique and essential source of knowledge. (shrink)

In 1896 William James published an essay entitled The Will to Believe, in which he defended the legitimacy of religious faith against the attacks of such champions of scientific method as W.K. Clifford and Thomas Huxley. James's work quickly became one of the most important writings in the philosophy of religious belief. James Wernham analyses James's arguments, discusses his relation to Pascal and Renouvier, and considers the interpretations, and misinterpretations, of James's major critics. Wernham shows (...) convincingly that James was unaware of many destructive ambiguitities in his own doctrines and arguments, although clear and consistent in his view that our obligation to believe in theism is not a moral but a prudential obligation -- a foolish-not-to-believe doctrine, rather than a not-immoral-to-believe one. Wernham also shows that the doctrine is best read as affirming the wisdom of gambling that God exists, a notion which James failed to distinguish from believing and which, among other things, he explicitly identified with faith. James's pragmatism, a theory concerning the meaning of truth, is shown to be quite distinct from the doctrine of The Will to Believe. In concentrating on a careful analysis of this doctrine of the will-to-believe, Wernham not only makes a major contribution to understanding James's philosophy, but also clarifies issues in the philosophy of religion and in the analysis of belief and faith. (shrink)

This new critical edition is an examination of William James's Essays in Radical Empiricism in light of the scientific naturalism prominent in James's Principles of Psychology (1890) and the subsequent development of Darwinian, functional psychology and functionalism in psychology, the philosophy psychology and the philosophy of mind.

James McCosh, the Scottish philosopher, graduated from the University of Glasgow, spent some time as a minister in the Church of Scotland but then returned to philosophy and spent most of his career at Princeton University. The eighteenth-century Scottish Enlightenment had many influential philosophers at its core. In this book, first published in 1875, McCosh outlines the theories of eighteenth- and nineteenth-century philosophers and identifies Scottish philosophy as a distinct school of thought. He summarises both the merits and the (...) possible criticisms of each philosopher's work and also gives detailed biographical information. Among the philosophers discussed are the influential David Hume, Thomas Reid and Adam Smith. The final chapter focuses on Sir William Hamilton, a philosopher who greatly influenced McCosh. (shrink)