This paper studies methodologically robust options for giving logical contents to nodes in abstract argumentation networks. It defines a variety of notions of attack in terms of the logical contents of the nodes in a network. General properties of logics are refined both in the object level and in the metalevel to suit the needs of the application. The network-based system improves upon some of the attempts in the literature to define attacks in terms of defeasible proofs, the (...) so-called rule-based systems. We also provide a number of examples and consider a rigorous case study, which indicate that our system does not suffer from anomalies. We define consequence relations based on a notion of defeat, consider rationality postulates, and prove that one such consequence relation is consistent. (shrink)

The aim of this paper is to examine W. V.Quine's theory of infants' early acquisition oflanguage, with a narrow focus on Quine's theory ofobservation sentences. Intersubjectivity and sensoryexperiences, the two features that characterise thenotion, receive the most attention. It is argued,following a suggestion from Donald Davidson, thatQuine favours a proximal theory of languageacquisition, i.e., a theory which is focused onprivate experiences as ultimate sources ofstimulation, contrary to a distal theory, where thestimulus source is located in externally observableobjects and events. I (...) use the philosophical criticismof Donald Davidson, Dagfinn Føllesdal and CharlesTaylor to suggest an alternative account of languageacquisition, which emphasises the primacy ofparticipation and joint attention to external stimuli.I argue that such an alternative theory is moreconsistent with recent studies in child developmentand language acquisition. (shrink)

A hypermodality is a connective □ whose meaning depends on where in the formula it occurs. The paper motivates the notion and shows that hypermodal logics are much more expressive than traditional modal logics. In fact we show that logics with very simple K hypermodalities are not complete for any neighbourhood frames.

This paper presents the philosophical and theological underpinnings of the so-called “world-picture logic” mode of critique. It also outlines the arguments—empirical, transcendental and creationist—upon which the aesthetic framework depends that has the world relational picture as its object. By laying out these arguments and inquiring into the nature of what is human, it sketches the relational theology central to the “world-picture logic” mode of critique.

We present a conceptual analysis of the notions of actual physical property and potential physical property as used by theoretical physicists/mathematicians working in the domain of operational quantum logic. We investigate how these notions are being used today and what role they play in the specified field of research. In order to do so, we will give a brief introduction to this area of research and explain it as a part of the discipline known as “mathematical metascience”. An in depth (...) analysis of Aristotle’s use of the notions of “actuality” and “potentiality” is presented in order to point out exactly how much of the Aristotelian connotations are embedded in the contemporary use of the concepts under investigation. Although we will not focus in depth on all the drawbacks in the early historical development of physics due to the overwhelming influence of Aristotle’s writings, our analysis does touch upon some aspects of the Aristotelian theory of movement that are often overthrown nowadays. (shrink)

When one side is illuminated, the other side remains in darkness.My reason for addressing the topic for this article is to attempt a philosophical reconstruction of the "logic of not" in such a way as to guide us into entertaining a holistic mode of thinking. In preparation for this investigation, for comparative purposes I will engage a conceptual paradigm that is dominant in the Western philosophical tradition, namely the paradigm that is framed in terms of an either-or, ego-logical (...) dualistic stance and that undergirds our daily life in knowing and understanding thing-events. I will use the phrase "thing-event" throughout this article as a way of attempting to capture a sense of the whole rather than thematizing... (shrink)

The concept of the subject, of what Hegel calls absolute negativity, already appears early in the logic of being.1 Absolute negativity, negation of the negation, occurs throughout the logic as identity in difference understood as self-identification under different descriptions. First, the subject refers to itself merely under an incomplete description. Secondly, it refers to something other than itself under a second description which is logically required by the first. (For example, the description of being in general requires some determinate description (...) of being in particular). But this second description is dialectically excluded by the assumption that the first description is complete. Thirdly, the subject negates its negation of the other. It discovers itself in the other, under the other description, and thus comes to refer to itself less incompletely. This is Hegel in the analytic mode. (shrink)

To readers of the Science of Logic, “mode” signifies the externality of the absolute, and its proper place within the text is at the level of the determinations of reflection, within the Doctrine of Essence. Let us take a look at the third section of the Doctrine of Essence: “Actuality”. In its broadest meaning, this signifies “reflected absoluteness,” that is to say, the unity of essence and existence; therefore, it is not a purely immediate existence, but “the immediate unity (...) of form between inner and outer.” Through this definition, a new kind of logical process is made possible - that of the actual totality’s self-manifestation. In the opening chapter of this section, headed “The Absolute,” the determination of the absolute is carried through from its initial unity to truly absolute identity by means of the complex play of reflection. Hegel’s treatment of this subject is beyond the scope of this paper; but if, at the initial stage of its dialectical cycle, reflection is external to the absolute - instead of being the proper determination of it - then it can at least be observed that in the third subdivision of the chapter what is under consideration is the negative return of the absolute into itself, and that this return is accomplished in such a way that “mode” is both the externality of the absolute and its reflection into itself: its being into itself and for itself. As one of the recent commentators on the Science of Logic has pointed out: “Le mode est ‘1’apparance comme apparance’: avec lui se profile un type d’extériorité qui ne sera plus en dette à l’egard d’une interiorité … la manifestation de l’absolu n’est pas une sortie de soi, mais plutôt sa constitution dans l’exteriorité des modes, puis des modalités de l’effectivité.”. (shrink)

Summary: The aim of this paper is to explore the relationships between Buridan’s logic and the ontology of modes modi). Modes, not considered to be really distinct from absolute entities, could serve to reduce the ontological commitment of the theory of the categories, and thus they were to become ubiquitous in this role in late medieval and early modern philosophy. After a brief analysis of the most basic argument for the real distinction between entities of several categories (“the argument from (...) separability”), I point out that despite nominalist charges to the contrary, “older realists”—that is, authors working before and around Ockham’s time—were not committed to such real distinctions, and thus to an overpopulated ontology, by their.. (shrink)

The volume collects essays by an international team of philosophers aimed at elucidating three fundamental and interconnected themes in ontology. In the first instance, there is the issue of the kind of thing that, in the primary sense, is or exists: must the primitive terms be particular or universal? Any reply will itself raise the question of how to treat discourse that appears to refer to things that cannot be met with in time and space: what difference is there between (...) saying that someone is not sad and saying that something does not exist? If we can speak meaningfully about fictions, what makes those statements true and how can the entities in question be identified? Assessment of the options that have been opened up in these fields since the work of Bertrand Russell and Alexius Meinong at the beginning of the twentieth century remains an important testing-ground for metaphysical principles and intuitions. (shrink)

Currently available systems of action deontic logic are not designed to model procedures to assess the conduct of an agent which take into account the intentions of the agent and the circumstances in which she is acting. Yet, procedures of this kind are essential to determine what counts as culpable not doing. In light of this, we design an action logic, AL, in which it is possible to distinguish actions that are objectively possible for an agent, viz. there are no (...) objective impediments for the agent to do them, and actions that, besides being objectively possible, are compatible with the setting or intentions of the agent. (shrink)

Appearing in the “Cairo Declaration on Human Rights in Islam” as an undefined referent for the limits on freedom of expression in Islam, Shariah is still to be chased as an indefinable referent which restricts freedom of the expression in the Islamic Republic of Iran. Iran’s Press Law as well as Constitution unveil Shariah’s referent to be a person: the Jurist-Ruler around whom a cult of personality is legalized in terms of “Imamate” and around whom all the limits on freedom (...) of expression revolve. Interpretation of Shariah is not a solution but part of the problem in Iran. Such problem can be dealt in terms of three modes of self-expression which were invented by the Iranian Reformists to avoid self-censorship. The notion of master-signifier can be the key to unraveling the problem of self-referentiality in freedom of expression and its Reformist solution in Iran’s legal system. (shrink)

Modes of rationality in nursing documentation: biology, biography, and the ‘voice of nursing’ This article is based on a discourse analysis of the complete nursing records of 45 patients, and concerns the modes of rationality that mediated text‐based accounts relating to patient care that nurses recorded. The analysis draws on the work of the critical theorist, Jürgen Habermas, who conceptualised rationality in the context of modernity according to two types: purposive rationality based on an instrumental logic, and value rationality based (...) on ethical considerations and moral reasoning. Our analysis revealed that purposive rationality dominated the content of nursing documentation, as evidenced by a particularly bio‐centric and modernist construction of the workings of the body within the texts. There was little reference in the documentation to central themes of contemporary nursing discourses, such as notions of partnership, autonomy, and self‐determination, which are associated with value rationality. Drawing on Habermas, we argue that this nursing documentation depicted the colonisation of the sociocultural lifeworld by the bio‐technocratic system. Where nurses recorded disagreements that patients had with medical regimes, the central struggle inherent in the project of modernity became transparent — the tension between the rational and instrumental control of people through scientific regulation and the autonomy of the subject. The article concludes by problematising communicative action within the context of nursing practice. (shrink)

Of the different modes that characterize Michael Gilbert’s multi-modal theory of argumentation, the kisceral is in many ways the most challenging to understand and employ. It appears to bypass the processes of reason that have dominated accounts in the Western tradition, diverting us toward the private worlds of hunches and gut reactions. This paper explores the nature of kisceral arguments, comparing them to the way intuition operates in William James’ examination of mystical experience. Having provided an account of kisceral arguments (...) and their operation, the discussion turns to the even more challenging issue of how such arguments should be evaluated. (shrink)

This article returns to the debate about the relative importance of the productive forces and the relations of production in the feudal mode of production. It argues, using western medieval evidence, that this relation is an empirical one and varies between modes, maybe also inside modes; and that, in the specific case of feudalism, not only were the relations of production the driving force, but developments in the productive forces actually depended upon them.

The fact that many modal operators are part of an adjunction is probably folklore since the discovery of adjunctions. On the other hand, the natural idea of a minimal propositional calculus extended with a pair of adjoint operators seems to have been formulated only very recently. This recent research, mainly motivated by applications in computer science, concentrates on technical issues related to the calculi and not on the significance of adjunctions in modal logic. It then seems a worthy enterprise (both (...) for these contemporary topical pursuits and also for historical interest) to trace the concept of adjunction back to the origins of the algebraic semantics of modal logic and to make explicit its ubiquity in this branch of mathematics. (shrink)

The logical empiricists expressed a consistent attitude to racial categorisation in both the ethical and scientific spheres. Their attitude may be captured in the following slogan: human racial taxonomy is an empirically meaningful mode of classifying persons that we should refrain from deploying. I offer an interpretation of their position that would render coherent their remarks on race with positions they adopted on the scientific status of taxonomy in general, together with their potential moral or political motivations for (...) adopting that position. (shrink)

This article considers distinct ways of understanding the world, referred to in psychology as Functions of Consciousness or as Cognitive Modes, having as the scope of interest epistemology and natural sciences. Inspired by C.G. Jung's Simile of the Spectrum, we consider three basic cognitive modes associated to: (R) embodied instinct, experience, and action; (G) reality perception and learning; and (B) concept abstraction, rational thinking, and language. RGB stand for the primary colors: red, green, and blue. Accordingly, a conceptual map between (...) cognitive modes and primary and secondary colors is built based on the physics and physiology of color perception and epistemological characteristics of the aforementioned cognitive modes, leading to logical relations structured as an Hexagon of Opposition. Finally, this model of cognitive modes is applied to the analysis and interpretation of some important episodes in the historical development of physics and technology. (shrink)

Conditional logics have traditionally been intended to formalize various intuitively correct modes of reasoning involving conditional expressions in natural language. Although conditional logics have by now been thoroughly studied in a classical context, they have yet to be systematically examined in an intuitionistic context, despite compelling philosophical and technical reasons to do so. This paper addresses this gap by thoroughly examining the basic intuitionistic conditional logic ICK, the intuitionistic counterpart of Chellas’ important classical system CK. I give ICK both worlds (...) semantics and algebraic semantics, and prove that these are equivalent. I give a Gödel-type embedding of ICK into CK and a Glivenko-type embedding of CK into ICK. I axiomatize ICK and prove soundness, completeness, and decidability results. Finally, I discuss extending ICK. (shrink)

The Destructions of the Modes of Signifying (henceforth: dms) is an anonymous fourteenth-century polemic against modist speculative grammar (grammatica speculativa). Wielding Ockhamist logic and metaphysics, the dms repeatedly attacks the very root of modism: the claim that the grammatical features of language are grounded in the metaphysical properties of the world. I call this the Modist Correspondence Thesis (henceforth: mct). In its most general form, mct says that every mode of signifying exhibited by an utterance corresponds to a (...) class='Hi'>mode of being exhibited by a thing. The Emptiness Argument of the dms tries to show that mct fails to accommodate certain special cases, such as privative, fictitious, and divine utterances, like ‘blindness’ (caecitas), ‘chimera’ (chimaera), and ‘deity’ (deitas). The modist Thomas of Erfurt directly addresses the Emptiness Argument, anticipating the anti-modist criticisms present in the dms. In doing so, he points the way to alternative formulations of mct that are immune to those criticisms. (shrink)

Evaluative studies of inductive inferences have been pursued extensively with mathematical rigor in many disciplines, such as statistics, econometrics, computer science, and formal epistemology. Attempts have been made in those disciplines to justify many different kinds of inductive inferences, to varying extents. But somehow those disciplines have said almost nothing to justify a most familiar kind of induction, an example of which is this: “We’ve seen this many ravens and they all are black, so all ravens are black.” This is (...) enumerative induction in itsfullstrength. For it does not settle with a weaker conclusion (such as “the ravens observed in the future will all be black”); nor does it proceed with any additional premise (such as the statistical IID assumption). The goal of this paper is to take some initial steps toward a justification for the full version of enumerative induction, against counterinduction, and against the skeptical policy. The idea is to explore various epistemic ideals, mathematically defined as different modes of convergence to the truth, and look for one that is weak enough to be achievable and strong enough to justify a norm that governs both the long run and the short run. So the proposal is learning-theoretic in essence, but a Bayesian version is developed as well. (shrink)

Individualism comes in at least ten modes: ontological, logical, semantic, epistemological, methodological, axiological, praxiological, ethical, historical, and political. These modes are bound together. For example, ontological individualism motivates the thesis that relations are n-tuples of individuals, as well as radical reductionism and libertarianism. The flaws and merits of all ten sides of the individualist decagon are noted. So are those of its holist counterpart. It is argued that systemism has all the virtues and none of the defects of individualism (...) and holism. One such virtue is the ability to recognize that individualism is a system rather than an unstructured bag of opinions--which raises the question whether thorough and consistent individualism is at all possible. Key Words: holism • individualism • system • systemism. (shrink)

Conditional logics were originally developed for the purpose of modeling intuitively correct modes of reasoning involving conditional—especially counterfactual—expressions in natural language. While the debate over the logic of conditionals is as old as propositional logic, it was the development of worlds semantics for modal logic in the past century that catalyzed the rapid maturation of the field. Moreover, like modal logic, conditional logic has subsequently found a wide array of uses, from the traditional (e.g. counterfactuals) to the exotic (e.g. conditional (...) obligation). Despite the close connections between conditional and modal logic, both the technical development and philosophical exploitation of the latter has outstripped that of the former, with the result that noticeable lacunae exist in the literature on conditional logic. My dissertation addresses a number of these underdeveloped frontiers, producing new technical insights and philosophical applications. -/- I contribute to the solution of a problem posed by Priest of finding sound and complete labeled tableaux for systems of conditional logic from Lewis' V-family. To develop these tableaux, I draw on previous work on labeled tableaux for modal and conditional logic; errors and shortcomings in recent work on this problem are identified and corrected. While modal logic has by now been thoroughly studied in non-classical contexts, e.g. intuitionistic and relevant logic, the literature on conditional logic is still overwhelmingly classical. Another contribution of my dissertation is a thorough analysis of intuitionistic conditional logic, in which I utilize both algebraic and worlds semantics, and investigate how several novel embedding results might shed light on the philosophical interpretation of both intuitionistic logic and conditional logic extensions thereof. -/- My dissertation examines deontic and connexive conditional logic as well as the underappreciated history of connexive notions in the analysis of conditional obligation. The possibility of interpreting deontic modal logics in such systems (via embedding results) serves as an important theoretical guide. A philosophically motivated proscription on impossible obligations is shown to correspond to, and justify, certain (weak) connexive theses. Finally, I contribute to the intensifying debate over counterpossibles, counterfactuals with impossible antecedents, and take—in contrast to Lewis and Williamson—a non-vacuous line. Thus, in my view, a counterpossible like "If there had been a counterexample to the law of the excluded middle, Brouwer would not have been vindicated" is false, not (vacuously) true, although it has an impossible antecedent. I exploit impossible (non-normal) worlds—originally developed to model non-normal modal logics—to provide non-vacuous semantics for counterpossibles. I buttress the case for non-vacuous semantics by making recourse to both novel technical results and theoretical considerations. (shrink)

Illuminates legal reasoning -- and its justification At least since plato and Aristotle, thinkers have pondered the relationship between philosophical arguments and the "sophistical" arguments offered by the Sophists -- who were the first professional lawyers. Judges wield substantial political power, and the justifications they offer for their decisions are a vital means by which citizens can assess the legitimacy of how that power is exercised. However, to evaluate judicial justifications requires close attention to the method of reasoning behind decisions. (...) This new collection illuminates and explains the political and moral importance in justifying the exercise of judicial power. Explores enduring questions Focusing on work over the past century, the essays address important recurring questions, such as: When a judge or a lawyer reasons to a conclusion about what is legally required in a given case, must he also ask what is morally required? To what extent do a judge's personal, political, or moral biases affect his legal reasoning? What is the impact of such biases? Can all such biases be avoided? Is legal reasoning similar to reasoning in mathematics, logic, and linguistics, the physical sciences, the social sciences, or literature and history? Do formal logical modes of argument play any roles in legal reasoning? Solid coverage, well organized The articles were chosen to present some of the most influential works on the topic, as well as less familiar works that are thought provoking and informative. Each volume also offers a representative range of theoretical approaches to its topic, contains an introduction that locates the subject within the larger framework oftheories of legal reasoning and jurisprudence, and includes bibliographical notes on further readings. Many 19th century legal theorists argued that deduction is the central mode of legal reasoning, and that legal argument is like a deductive proof in mathematics or logic. They were attracted to this "deductivist" concept because it suggested that legal reasoning could be politically and morally neutral. This volume brings together some of the most thought-provoking articles on both sides of the debate. It also contains several leading articles that explain the role of probabilistic judgments and presumptions in various types of legal arguments, including the laws of evidence and criminal procedure. The collection is a solid introduction to the basic modes of logical argument in legal reasoning. (shrink)

Through a detailed analysis of the various modes of argumentation employed by Aristotle throughout his natural scientific works, I aim to contribute to the growing scholarship on the relation between Aristotle’s theory of science and his actual scientific practice. I challenge the standard reading of Aristotle as a methodological empiricist and show that he permits a variety of non-empirical arguments to support controversial theses in properly scientific contexts. Specifically, I examine his use of logical (logikôs) argumentation in the discussion (...) of mule sterility in Generation of Animals II 8, rational (kata ton logon) argumentation in his discussion of cardiocentrism throughout the biological works, and the method of division in Posterior Analytics II 13. (shrink)

This article considers distinct ways of understanding the world, referred to in psychology as functions of consciousness or as cognitive modes, having as the scope of interest epistemology and natural sciences. Inspired by C.G. Jung’s simile of the spectrum, we consider three basic cognitive modes associated to: (R) embodied instinct, experience, and action; (G) reality perception and learning; and (B) concept abstraction, rational thinking, and language. RGB stand for the primary colors: red, green, and blue. Accordingly, a conceptual map between (...) cognitive modes and primary and secondary colors is built based on the physics and physiology of color perception and epistemological characteristics of the aforementioned cognitive modes, leading to logical relations structured as an hexagon of opposition. Finally, this model of cognitive modes is applied to the analysis and interpretation of some important episodes in the historical development of physics and technology. (shrink)

The standard “gladiatorial” interpretation of the Modes of Agrippa has undergone several recent attacks. Scholars have criticized it because it seems to portray the skeptic as a dogmatist about logical support and because it does not treat all five Modes as part of the system. Although some have attempted to patch up the standard interpretation to address these issues, I raise a further problem: The gladiatorial interpretation cannot make sense of the skeptic using the Modes on herself, to suspend (...) her own judgment. In light of these problems, I propose a fresh interpretation: The Agrippan Modes should be understood, not as arguments (or argument forms), but as types of dialectical challenge that the skeptic can use in an endless inquiry into any dogmatic position. (shrink)

The mnemonic arts and the idea of a universal language that would capture the essence of all things were originally associated with cryptology, mysticism, and other occult practices. And it is commonly held that these enigmatic efforts were abandoned with the development of formal logic in the seventeenth century and the beginning of the modern era. In his distinguished book, Logic and the Art of Memory Italian philosopher and historian Paolo Rossi argues that this view is belied by an examination (...) of the history of the idea of a universal language. Based on comprehensive analyses of original texts, Rossi traces the development of this idea from late medieval thinkers such as Ramon Lull through Bruno, Bacon, Descartes, and finally Leibniz in the seventeenth century. The search for a symbolic mode of communication that would be intelligible to everyone was not a mere vestige of magical thinking and occult sciences, but a fundamental component of Renaissance and Enlightenment thought. Seen from this perspective, modern science and combinatorial logic represent not a break from the past but rather its full maturity. Available for the first time in English, this book (originally titled Clavis Universalis ) remains one of the most important contributions to the history of ideas ever written. In addition to his eagerly anticipated translation, Steven Clucas offers a substantial introduction that places this book in the context of other recent works on this fascinating subject. A rich history and valuable sourcebook, Logic and the Art of Memory documents an essential chapter in the development of human reason. (shrink)

Modal logic is one of philosophy’s many children. As a mature adult it has moved out of the parental home and is nowadays straying far from its parent. But the ties are still there: philosophy is important to modal logic, modal logic is important for philosophy. Or, at least, this is a thesis we try to defend in this chapter. Limitations of space have ruled out any attempt at writing a survey of all the work going on in our field—a (...) book would be needed for that. Instead, we have tried to select material that is of interest in its own right or exemplifies noteworthy features in interesting ways. Here are some themes that have guided us throughout the writing: • The back-and-forth between philosophy and modal logic. There has been a good deal of give-and-take in the past. Carnap tried to use his modal logic to throw light on old philosophical questions, thereby inspiring others to continue his work and still others to criticise it. He certainly provoked Quine, who in his turn provided—and continues to provide—a healthy challenge to modal logicians. And Kripke’s and David Lewis’s philosophies are connected, in interesting ways, with their modal logic. Analytic philosophy would have been a lot different without modal logic! • The interpretation problem. The problem of providing a certain modal logic with an intuitive interpretation should not be conflated with the problem of providing a formal system with a model-theoretic semantics. An intuitively appealing model-theoretic semantics may be an important step towards solving the interpretation problem, but only a step. One may compare this situation with that in probability theory, where definitions of concepts like ‘outcome space’ and ‘random variable’ are orthogonal to questions about “interpretations” of the concept of probability. • The value of formalisation. Modal logic sets standards of precision, which are a challenge to—and sometimes a model for—philosophy. Classical philosophical questions can be sharpened and seen from a new perspective when formulated in a framework of modal logic. On the other hand, representing old questions in a formal garb has its dangers, such as simplification and distortion. • Why modal logic rather than classical (first or higher order) logic? The idioms of modal logic—today there are many!—seem better to correspond to human ways of thinking than ordinary extensional logic. (Cf. Chomsky’s conjecture that the NP + VP pattern is wired into the human brain.) In his An Essay in Modal Logic (1951) von Wright distinguished between four kinds of modalities: alethic (modes of truth: necessity, possibility and impossibility), epistemic (modes of being known: known to be true, known to be false, undecided), deontic (modes of obligation: obligatory, permitted, forbidden) and existential (modes of existence: universality, existence, emptiness). The existential modalities are not usually counted as modalities, but the other three categories are exemplified in three sections into which this chapter is divided. Section 1 is devoted to alethic modal logic and reviews some main themes at the heart of philosophical modal logic. Sections 2 and 3 deal with topics in epistemic logic and deontic logic, respectively, and are meant to illustrate two different uses that modal logic or indeed any logic can have: it may be applied to already existing (non-logical) theory, or it can be used to develop new theory. (shrink)

Two modes of reasoning are used by humans – the `theoretical' (formal) and the `empirical' (non-formal), the first operating with inside-the-syllogism information, the second utilising out-of-the-syllogism information. Cross-cultural research (since Lévy-Bruhl, and especially after Luria) and developmental research (since Piaget) discovered respectively that members of `traditional' societies and children up to a certain age are able to operate only in the empirical mode.The paper brings together diverse discussions about usage of these modes in actual discourse (Ennis, Johnson-Laird, Moore, Olson, (...) Ong, etc.). It concentrates on contradictory opinions as to whether contemporary individuals after they acquire the formal mode preserve and utilise the empirical mode. In this connection it discusses results of neurological experiments investigating performance in solving syllogisms under conditions of transitory suppression of the left or the right hemisphere (Deglin et al.) which demonstrated that one and the same person, depending on which hemisphere is suppressed, uses both strategies. The activated right hemisphere utilizes the `empirical' pattern, the activated left hemisphere utilizes the `logical' pattern. Thus both mechanisms of reasoning are present in the brain simultaneously, but each of them is controlled by different hemispheres. (shrink)

Judaic Logic is an original inquiry into the forms of thought determining Jewish law and belief, from the impartial perspective of a logician. Judaic Logic attempts to honestly estimate the extent to which the logic employed within Judaism fits into the general norms, and whether it has any contributions to make to them. The author ranges far and wide in Jewish lore, finding clear evidence of both inductive and deductive reasoning in the Torah and other books of the Bible, and (...) analyzing the methodology of the Talmud and other Rabbinic literature by means of formal tools which make possible its objective evaluation with reference to scientific logic. The result is a highly innovative work – incisive and open, free of clichés or manipulation. Judaic Logic succeeds in translating vague and confusing interpretative principles and examples into formulas with the clarity and precision of Aristotelean syllogism. Among the positive outcomes, for logic in general, are a thorough listing, analysis and validation of the various forms of a-fortiori argument, as well as a clarification of dialectic logic. However, on the negative side, this demystification of Talmudic/Rabbinic modes of thought (hermeneutic and heuristic) reveals most of them to be, contrary to the boasts of orthodox commentators, far from deductive and certain. They are often, legitimately enough, inductive. But they are also often unnatural and arbitrary constructs, supported by unverifiable claims and fallacious techniques. Many other thought-processes, used but not noticed or discussed by the Rabbis, are identified in this treatise, and subjected to logical review. Various more or less explicit Rabbinic doctrines, which have logical significance, are also examined in it. In particular, this work includes a formal study of the ethical logic (deontology) found in Jewish law, to elicit both its universal aspects and its peculiarities. With regard to Biblical studies, one notable finding is an explicit formulation (which, however, the Rabbis failed to take note of and stress) of the principles of adduction in the Torah, written long before the acknowledgement of these principles in Western philosophy and their assimilation in a developed theory of knowledge. Another surprise is that, in contrast to Midrashic claims, the Tanakh (Jewish Bible) contains a lot more than ten instances of qal vachomer (a-fortiori) reasoning. In sum, Judaic Logic elucidates and evaluates the epistemological assumptions which have generated the Halakhah (Jewish religious jurisprudence) and allied doctrines. Traditional justifications, or rationalizations, concerning Judaic law and belief, are carefully dissected and weighed at the level of logical process and structure, without concern for content. This foundational approach, devoid of any critical or supportive bias, clears the way for a timely reassessment of orthodox Judaism (and incidentally, other religious systems, by means of analogies or contrasts). Judaic Logic ought, therefore, to be read by all Halakhists, as well as Bible and Talmud scholars and students; and also by everyone interested in the theory, practise and history of logic. (shrink)

Ontological pluralism is the doctrine that there are different ways or modes of being. In contemporary guise, it is the doctrine that a logically perspicuous description of reality will use multiple quantifiers which cannot be thought of as ranging over a single domain. Although thought defeated for some time, recent defenses have shown a number of arguments against the view unsound. However, another worry looms: that despite looking like an attractive alternative, ontological pluralism is really no different than its counterpart, (...) ontological monism. In this paper, after explaining the worry in detail, I argue that considerations dealing with the nature of the logic ontological pluralists ought to endorse, coupled with an attractive philosophical thesis about the relationship between logic and metaphysics, show this worry to be unfounded. (shrink)

The Logic of Causation: Definition, Induction and Deduction of Deterministic Causality is a treatise of formal logic and of aetiology. It is an original and wide-ranging investigation of the definition of causation (deterministic causality) in all its forms, and of the deduction and induction of such forms. The work was carried out in three phases over a dozen years (1998-2010), each phase introducing more sophisticated methods than the previous to solve outstanding problems. This study was intended as part of a (...) larger work on causal logic, which additionally treats volition and allied cause-effect relations (2004). The Logic of Causation deals with the main technicalities relating to reasoning about causation. Once all the deductive characteristics of causation in all its forms have been treated, and we have gained an understanding as to how it is induced, we are able to discuss more intelligently its epistemological and ontological status. In this context, past theories of causation are reviewed and evaluated (although some of the issues involved here can only be fully dealt with in a larger perspective, taking volition and other aspects of causality into consideration, as done in Volition and Allied Causal Concepts). Phase I: Macroanalysis. Starting with the paradigm of causation, its most obvious and strongest form, we can by abstraction of its defining components distinguish four genera of causation, or generic determinations, namely: complete, partial, necessary and contingent causation. When these genera and their negations are combined together in every which way, and tested for consistency, it is found that only four species of causation, or specific determinations, remain conceivable. The concept of causation thus gives rise to a number of positive and negative propositional forms, which can be studied in detail with relative ease because they are compounds of conjunctive and conditional propositions whose properties are already well known to logicians. The logical relations (oppositions) between the various determinations (and their negations) are investigated, as well as their respective implications (eductions). Thereafter, their interactions (in syllogistic reasoning) are treated in the most rigorous manner. The main question we try to answer here is: is (or when is) the cause of a cause of something itself a cause of that thing, and if so to what degree? The figures and moods of positive causative syllogism are listed exhaustively; and the resulting arguments validated or invalidated, as the case may be. In this context, a general and sure method of evaluation called ‘matricial analysis’ (macroanalysis) is introduced. Because this (initial) method is cumbersome, it is used as little as possible – the remaining cases being evaluated by means of reduction. Phase II: Microanalysis. Seeing various difficulties encountered in the first phase, and the fact that some issues were left unresolved in it, a more precise method is developed in the second phase, capable of systematically answering most outstanding questions. This improved matricial analysis (microanalysis) is based on tabular prediction of all logically conceivable combinations and permutations of conjunctions between two or more items and their negations (grand matrices). Each such possible combination is called a ‘modus’ and is assigned a permanent number within the framework concerned (for 2, 3, or more items). This allows us to identify each distinct (causative or other, positive or negative) propositional form with a number of alternative moduses. This technique greatly facilitates all work with causative and related forms, allowing us to systematically consider their eductions, oppositions, and syllogistic combinations. In fact, it constitutes a most radical approach not only to causative propositions and their derivatives, but perhaps more importantly to their constituent conditional propositions. Moreover, it is not limited to logical conditioning and causation, but is equally applicable to other modes of modality, including extensional, natural, temporal and spatial conditioning and causation. From the results obtained, we are able to settle with formal certainty most of the historically controversial issues relating to causation. Phase III: Software Assisted Analysis. The approach in the second phase was very ‘manual’ and time consuming; the third phase is intended to ‘mechanize’ much of the work involved by means of spreadsheets (to begin with). This increases reliability of calculations (though no errors were found, in fact) – but also allows for a wider scope. Indeed, we are now able to produce a larger, 4-item grand matrix, and on its basis find the moduses of causative and other forms needed to investigate 4-item syllogism. As well, now each modus can be interpreted with greater precision and causation can be more precisely defined and treated. In this latest phase, the research is brought to a successful finish! Its main ambition, to obtain a complete and reliable listing of all 3-item and 4-item causative syllogisms, being truly fulfilled. This was made technically feasible, in spite of limitations in computer software and hardware, by cutting up problems into smaller pieces. For every mood of the syllogism, it was thus possible to scan for conclusions ‘mechanically’ (using spreadsheets), testing all forms of causative and preventive conclusions. Until now, this job could only be done ‘manually’, and therefore not exhaustively and with certainty. It took over 72’000 pages of spreadsheets to generate the sought for conclusions. This is a historic breakthrough for causal logic and logic in general. Of course, not all conceivable issues are resolved. There is still some work that needs doing, notably with regard to 5-item causative syllogism. But what has been achieved solves the core problem. The method for the resolution of all outstanding issues has definitely now been found and proven. The only obstacle to solving most of them is the amount of labor needed to produce the remaining (less important) tables. As for 5-item syllogism, bigger computer resources are also needed. (shrink)

Contrary to the received view, decision theory is not primarily devoted to instrumental (ends-to-means) reasoning. Instead, its major preoccupation is the derivation of ends from other ends. Given preferences over basic alternatives, it constructs preferences over alternatives that have been modified through the addition of value object modifiers (modes) that specify probability, uncertainty, distance in time etc. A typology of the decision-theoretical modes is offered. The modes do not have (even extrinsic) value, but they transform the value of objects to (...) which they are applied. A rational agent's total set of preferences should be coherent, but from this it does not follow that her preferences over mode-containing objects have to be derivable from her preferences over mode-free objects. (shrink)

The author investigates how the conception of legal validity as a specific mode of existence, adopted by Kelsen in Allgemeine Theorie der Normen (General Theory of Norms), can be reconciled with a conception of the legal system in which conflicts of legal norms remain of logical concern. To this end he makes use of Ludwig Wittgenstein's picture theory of the proposition as set out in the Tractatus Logico-Philosophicus. The conclusion is that in order to reconcile the two conceptions, (...) the legal system itself must be conceived of as consisting of three sub-systems, namely, (i) a sub-system of perceptible legal judgments, (ii) a sub-system of valid legal conditions, and (iii) a sub-system of observable social practices. (shrink)