We explore the psychological foundations of Logic and Artificial Intelligence, touching on representation, categorisation, heuristics, consciousness, and emotion. Specifically, we challenge Dennett's view of the brain as a syntactic engine that is limited to processing symbols according to their structural properties. We show that cognitive psychology and neurobiology support a dual-process model in which one form of cognition is essentially semantical and differs in important ways from the operation of a syntactic engine. The dual-process model illuminates two important events in (...) Logic and Artificial Intelligence, namely the emergence of non-monotonicity and of embodiment, events that changed the traditional paradigms of ‘Logic = the study of deductive inference' and ‘Symbolic AI'. S. Afr. J. Philos. Vol.24(2) 2005: 137-151. (shrink)

Unrestricted use of the axiom schema of comprehension, ?to every mathematically (or set-theoretically) describable property there corresponds the set of all mathematical (or set-theoretical) objects having that property?, leads to contradiction. In set theories of the Zermelo?Fraenkel?Skolem (ZFS) style suitable instances of the comprehension schema are chosen ad hoc as axioms, e.g.axioms which guarantee the existence of unions, intersections, pairs, subsets, empty set, power sets and replacement sets. It is demonstrated that a uniform syntactic description may be given of acceptable (...) instances of the comprehension schema, which include all of the axioms mentioned, and which in their turn are theorems of the usual versions of ZFS set theory. Well then, shall we proceed as usual and begin by assuming the existence of a single essential nature or Form for every set of things which we call by the same name? Do you understand? (Plato, Republic X.596a6; cf. Cornford 1966, 317). (shrink)

The intuitive notion of a binary relation on information-bearers, comparingthem with respect to their closeness to the available information, is oftenconstrued in terms of comparing their symmetric difference with, orcompositional similarity to, the available information. This happens forinstance in some treatments of verisimilitude. We expound an abstractmathematical rendering of the relevant data-dependent relation in theframework of Boolean algebras. For every element t of a Boolean algebra B we construct the t-modulated Boolean algebra Btin which the order relation represents `is at (...) most as compatible with t as'' or `is at best as similar to t as''. In the case of Lindenbaum-Tarskialgebras, t expresses the available information, and the compatibilityrelation turns out to be an entwinement of inferential and conjecturalrelations. It is just classical entailment when no information is available(i.e., when t is logically true) and becomes more boldly abductive themore information is available. The rich algebraic structures of a Boolean algebra –- including its Boolean group structures –- play a significant role in this combination of deduction and abduction and also induce cautious anddaring variants of the compatibility relation. Links with the literature onverisimilitude, abduction, and related topics are indicated. (shrink)

In this article, we redefine classical notions of theory reduction in such a way that model-theoretic preferential semantics becomes part of a realist depiction of this aspect of science. We offer a model-theoretic reconstruction of science in which theory succession or reduction is often better - or at a finer level of analysis - interpreted as the result of model succession or reduction. This analysis leads to 'defeasible reduction', defined as follows: The conjunction of the assumptions of a reducing theory (...) T with the definitions translating the vocabulary of a reduced theory T' to the vocabulary of T, defeasibly entails the assumptions of reduced T'. This relation of defeasible reduction offers, in the context of additional knowledge becoming available, articulation of a more flexible kind of reduction in theory development than in the classical case. Also, defeasible reduction is shown to solve the problems of entailment that classical homogeneous reduction encounters. Reduction in the defeasible sense is a practical device for studying the processes of science, since it is about highlighting different aspects of the same theory at different times of application, rather than about naive dreams concerning a metaphysical unity of science. (shrink)

Although AGM theory contraction (Alchourrón et al., 1985; Alchourrón and Makinson, 1985) occupies a central position in the literature on belief change, there is one aspect about it that has created a fair amount of controversy. It involves the inclusion of the postulate known as Recovery. As a result, a number of alternatives to AGM theory contraction have been proposed that do not always satisfy the Recovery postulate (Levi, 1991, 1998; Hansson and Olsson, 1995; Fermé, 1998; Fermé and Rodriguez, 1998; (...) Rott and Pagnucco, 1999). In this paper we present a new addition, systematic withdrawal, to the family of withdrawal operations, as they have become known. We define systematic withdrawal semantically, in terms of a set of preorders, and show that it can be characterised by a set of postulates. In a comparison of withdrawal operations we show that AGM contraction, systematic withdrawal and the severe withdrawal of Rott and Pagnucco (1999) are intimately connected by virtue of their definition in terms of sets of preorders. In a future paper it will be shown that this connection can be extended to include the epistemic entrenchment orderings of Gärdenfors (1988) and Gärdenfors and Makinson (1988) and the refined entrenchment orderings of Meyer et al. (2000). (shrink)

Consequence is at the heart of logic, and an account of consequence offers a vital tool in the evaluation of arguments. This text presents what the authors term as 'logical pluralism' arguing that the notion of logical consequence doesn't pin down one deductive consequence relation; it allows for many of them.

relative to the actual world) of a propositional theory are defined. A theory is ‘closer to the truth’ the logically stronger its positive content and the logically weaker its negative content. This proposal delivers the same verisimilar preordering of theories that has been defined by Brink and Heidema as a ‘power ordering’. The preordering may be collapsed to a partial ordering and then embedded into a complete distributive lattice. The preordering may also be refined to a partial ordering by (...) employing the ‘convex content’ and the ‘non-convex content’ of each theory. Philosophical implications and historical relations are discussed. (shrink)

Providing an original and systematic treatment of foundational issues in philosophy of religion, J. L. Schellenberg's new book addresses the structure of..

What happens when someone acts? A familiar answer goes like this. There is something that the agent wants, and there is an action that he believes conducive to its attainment. His desire for the end, and his belief in the action as a means, justify taking the action, and they jointly cause an intention to take it, which in turn causes the corresponding movements of the agent's body. I think that the standard story is flawed in several respects. The flaw (...) that will concern me in this paper is that the story fails to include an agent-or, more precisely, fails to cast the agent in his proper role. (shrink)

Abstract I argue that meaning in life is importantly influenced by bioloical ties. More specifically, I maintain that knowing one's relatives and especially one's parents provides a kind of self-knowledge that is of irreplaceable value in the life-task of identity formation. These claims lead me to the conclusion that it is immoral to create children with the intention that they be alienated from their bioloical relatives?for example, by donor conception.

The intuitive notion of a binary relation on information-bearers, comparingthem with respect to their closeness to the available information, is oftenconstrued in terms of comparing their symmetric difference with, orcompositional similarity to, the available information. This happens forinstance in some treatments of verisimilitude. We expound an abstractmathematical rendering of the relevant data-dependent relation in theframework of Boolean algebras. For every element t of a Boolean algebra B we construct the t-modulated Boolean algebra Btin which the order relation represents `is at (...) most as compatible with t as' or `is at best as similar to t as'. In the case of Lindenbaum-Tarskialgebras, t expresses the available information, and the compatibilityrelation turns out to be an entwinement of inferential and conjecturalrelations. It is just classical entailment when no information is available(i.e., when t is logically true) and becomes more boldly abductive themore information is available. The rich algebraic structures of a Boolean algebra –- including its Boolean group structures –- play a significant role in this combination of deduction and abduction and also induce cautious anddaring variants of the compatibility relation. Links with the literature onverisimilitude, abduction, and related topics are indicated. (shrink)

Retributive theories of punishment argue that punishing a criminal for a crime she committed is sufficient reason for a justified and morally permissible punishment. But what about when the state gets lucky in its decision to punish? I argue that retributive theories of punishment are subject to “Gettier” style cases from epistemology. Such cases demonstrate that the state needs more than to just get lucky, and as these retributive theories of punishment stand, there is no anti-luck condition. I’ll argue that (...) Gettier-style cases demonstrate an impermissible instance of punishment, even though they meet the conditions of retributive theories of punishment. Retributive theories are, therefore, too weak. The safety condition from epistemology provides the anti-luck condition needed for permissible punishment. I argue that two forms of retributivism, rights-forfeiture and what I call standard retributivism, are both subject to Gettier-style cases. Unlike the literature on standards of proof, this paper argues that safety is a condition on punishment itself, i.e., in all nearby possible worlds, the accuser must correctly accuse the convicted for the crime they actually committed. (shrink)

Supervaluationism is often described as the most popular semantic treatment of indeterminacy. There’s little consensus, however, about how to fill out the bare-bones idea to include a characterization of logical consequence. The paper explores one methodology for choosing between the logics: pick a logic thatnorms beliefas classical consequence is standardly thought to do. The main focus of the paper considers a variant of standard supervaluational, on which we can characterizedegrees of determinacy. It applies the methodology above to focus ondegree logic. (...) This is developed first in a basic, single-premise case; and then extended to the multipremise case, and to allowdegreesof consequence. The metatheoretic properties of degree logic are set out. On the positive side, the logic is supraclassical—all classical valid sequents are degree logic valid. Strikingly, metarules such as cut and conjunction introduction fail. (shrink)

v. 1. Nicomachean ethics. Politics. The Athenian Constitution. Rhetoric. On Poetics.--v. 2. Logic.--v. 3. Physics. Metaphysics. On the soul. Short physical treaties.--v. 4. On the heavens. On generation and corruption. Meteorology. Biological treatises.

The aim of this paper is to elaborate on the phenomenological approach to expertise as proposed by Dreyfus and Dreyfus and to give an account of the extent to which their approach may contribute to a better understanding of how athletes may use their cognitive capacities during high-level skill execution. Dreyfus and Dreyfus's non-representational view of experience-based expertise implies that, given enough relevant experience, the skill learner, when expert, will respond intuitively to immediate situations with no recourse to deliberate actions (...) or mental representations. The paper will subsequently outline some implications and consequences of such an approach and will also examine to what extent Dreyfus and Dreyfus's skill model is capable to resist different attacks that have been made against their view, and in particular regarding the practical application of their approach to the skill domain of competitive sport. (shrink)

In logic, including the designer logics of artificial intelligence, and in the philosophy of science, one is often concerned with qualitative, comparative orderings on the states of a system, or on theories expressing information about the system. States may be compared with respect to normality, or some preference criterium, or similarity to some given (set of) state(s). Theories may be compared with respect to logical power, or to truthlikeness, or to how well they capture certain information. We explain a number (...) of these relations, study their properties, and unravel some of their interrelationships. (shrink)

There are various contexts in which it is not pertinent to generate and attend to all the classical consequences of a given premiss—or to trace all the premisses which classically entail a given consequence. Such contexts may involve limited resources of an agent or inferential engine, contextual relevance or irrelevance of certain consequences or premisses, modelling everyday human reasoning, the search for plausible abduced hypotheses or potential causes, etc. In this paper we propose and explicate one formal framework for a (...) whole spectrum of consequence relations, flexible enough to be tailored for choices from a variety of contexts. We do so by investigating semantic constraints on classical entailment which give rise to a family of infra-classical logics with appealing properties. More specifically, our infra-classical reasoning demands (beyond ${\alpha\models\beta}$ ) that Mod(β) does not run wild, but lies within the scope (whatever that may mean in some specific context) of Mod(α), and which can be described by a sentence ${\bullet\alpha}$ with ${\beta\models\bullet\alpha}$ . Besides being infra-classical, the resulting logic is also non-monotonic and allows for non-trivial reasoning in the presence of inconsistencies. (shrink)

We introduce and explore the notion of duality for entailment relations induced by preference orderings on states. We discuss the relationship between these preferential entailment relations from the perspectives of Boolean algebra, inference rules, and modal axiomatisation. Interpreting the preference relations as accessibility relations establishes modular Gödel-Löb logic as a suitable modal framework for rational preferential reasoning.

This paper offers an alternate explanation of cases from the doxastic wronging literature. These cases violate what I call the degree of inquiry right—a novel account of zetetic obligations to inquire when interests are at stake. The degree of inquiry right is a moral right against other epistemic agents to inquire to a certain threshold when a belief undermines one’s interests. Thus, the agents are sometimes obligated to leave inquiry open. I argue that we have relevant interests in reputation, relationships, (...) and the well-being of our social groups. These interests generate obligations against others to “do their homework” before closing inquiry. This alternate account makes better sense of puzzles that accounts of doxastic wronging fall prey to. (shrink)

A common objection to Sosa’s epistemology is that it countenances, in an objectionable way, unsafe knowledge. This objection, under closer inspection, turns out to be in far worse shape than Sosa’s critics have realised. Sosa and his defenders have offered two central response types to the idea that allowing unsafe knowledge is problematic: one response type adverts to the animal/reflective knowledge distinction that is characteristic of bi-level virtue epistemology. The other less-discussed response type appeals to the threat of dream scepticism, (...) and in particular, to the idea that many of our everyday perceptual beliefs are unsafe through the nearness of the dream possibility. The latter dreaming response to the safety objection to Sosa’s virtue epistemology has largely flown under the radar in contemporary discussions of safety and knowledge. We think that, suitably articulated in view of research in the philosophy and science of dreaming, it has much more going for it than has been appreciated. This paper further develops, beyond what Sosa does himself, the dreaming argument in response to those who think safety (as traditionally understood) is a condition on knowledge and who object to Sosa’s account on the grounds that it fails this condition. The payoffs of further developing this argument will be not only a better understanding of the importance of insights about dreaming against safety as a condition on knowledge, but also some reason to think a weaker safety condition, one that is relativised to SSS (i.e., skill/shape/situation) conditions for competence exercise, gets better results all things considered as an anti-luck codicil on knowledge. (shrink)

The phenomenon of ambivalence is an important one for any philosophy of action. Despite this importance, there is a lack of a fully satisfactory analysis of the phenomenon. Although many contemporary philosophers recognize the phenomenon, and address topics related to it, only Harry Frankfurt has given the phenomenon full treatment in the context of action theory – providing an analysis of how it relates to the structure and freedom of the will. In this paper, I develop objections to Frankfurt's account, (...) all revolving around the charge that his account contains a serious ambiguity between willing and identifying. With such objections in place, I then develop an analysis that avoids the difficulties and ambiguities that Frankfurt's analysis is prey to. I briefly distinguish ambivalence from other types of internal conflict. This paper aims to offer conceptual clarification on the phenomenon of ambivalence, which will then allow for discussions about the normative merits and demerits of ambivalence, the effects of ambivalence on autonomous action, and methods of resolution of ambivalence. (shrink)

J. David Archibald explores how Darwin first came to the conclusion that species had evolved in different regions throughout the world. Carefully retracing Darwin's gathering of evidence and the evolution of his thinking, Origins of Darwin's Evolution achieves a new understanding of how Darwin crafted his transformative theory.

XLRI, in association with a few Tata Group companies, established the XLRI-JRD Tata Foundation in Business Ethics in 1991 to mark their long-standing commitment and contribution to business ethics in India. The foundation seeks to address this by publicly affirming the urgent need for ethics in business and the need to bring about a conducive culture in which it can thrive.

Abstract: Might knowledge normatively govern conversations and not just their discrete constituent thoughts and (assertoric) actions? I answer yes, at least for a restricted class of conversations I call aimed conversations. On the view defended here, aimed conversations are governed by participatory know-how - viz., knowledge how to do what each interlocutor to the conversation shares a participatory intention to do by means of that conversation. In the specific case of conversations that are in the service of joint inquiry, the (...) view defended is that interlocutors (A, B, ... n) must intentionally inquire together into whether p, by means of an aimed conversation X, only if A,B, ... n know how to use X to find out together whether p. The view is supported by considerations about instrumental rationality, shared intentionality, the epistemology of intentional action, as well as linguistic data. (shrink)

Lanczos, C. Einstein's path from special to general relativity.--Balazs, N. L. The acceptability of physical theories: Poincaré versus Einstein.--Ellis, G. F. R. Global and non-global problems in cosmology, by G. F. R. Ellis and D. W. Sciama.--Ehlers, J. The geometry of free fall and light propagation, by J. Ehlers, F. A. E. Pirani and A. Schild.--Trautman, A. Invariance of Lagrangian systems.--Penrose, R. The geometry of impulsive gravitational waves.--Exact solutions of the Einstein-Maxwell equations for an accelerated charge.--Taub, A. H. Plane-symmetric similarity (...) solutions for self-gravitating fluids.--Robinson, I. Equations of motion in the linear approximation, by I. Robinson and J. R. Robinson.--Florides, P. W. Rotating bodies in general relativity.--Chandrasekhar, S. A limiting case of relativistic equilibrium.--Israel, W. The relativistic Boltzmann equation.--Thompson, W. B. The self-consistent test-particle approach to relativistic kinetic theory. (shrink)

Immanuel Kant: The Very Idea of a Critique of Pure Reason is a study of the background, development, exposition, and justification of Kant's Critique of Pure Reason. Instead of examining Kant's arguments for the transcendental ideality of space and time, his deduction of the pure concepts of the understanding, or his account of the dialectic of human reason, J. Colin McQuillan focuses on Kant's conception of critique. By surveying the different ways the concept of critique was used during the eighteenth (...) century, the relationship between Kant's critique and his pre-critical experiments with different approaches to metaphysics, the varying definitions of a critique of pure reason Kant offers in the prefaces and introductions to the first Critique, and the way Kant responds to objections, McQuillan is able to highlight an aspect of Kant's critical philosophy that is too often overlooked—the reason that philosophy is critical. (shrink)

Every soul has an unconscious knowledge of the ultimate truth of things, a premise long taught by all great spiritual teachers, East and West, regularly experienced by those who follow the spiritual path. In the quest to help reestablish that universal connection, editor J. Douglas Kenyon has culled from the pages of Atlantis rising magazine this compilation of concise and well-illustrated articles by world-class researchers and theoreticians."--Back cover.

Greek Natural Philosophy presents the primary sources on the Presocratics in a straightforward way in order to tell a coherent story about the astonishing development of natural philosophy in ancient Greece and its relevance today... Greek Natural Philosophy is suitable for undergraduate and graduate courses in ancient Greek philosophy or in environmental philosophy, and will be of interest to scholars in this field.

Heidegger's neglect of value : Schelerian prospects -- The lived-experience of humanism in Husserl and James -- Participatory realism in Scheler's ethics -- Interpreting Scheler's Aktsein through Heidegger's Sein-in-der-Welt -- Phenomenological personalism -- Persons realizing values : how participatory realism works -- Embodying values : making values more concrete -- Finding hierarchy and phenomenological realism in James's affective intentionality -- Ethical non-naturalism and Schelerian participatory realism.

The first book of its kind, German Aesthetics assembles a who's who of German studies to explore 200 years of intellectual history, spanning literature, philosophy, politics, and culture.