Equivocation, or multiple meaning, is explained through the introduction of an additional response, the distinction, to points of order in formal dialogue objecting to immediate inconsistency.

Kit Fine’s arguments in Essence and Modality are widely accepted as being a decisive blow against modal essentialism. A selection of replies exist that have done little to counter the general view that modally construed essence is out of touch with what we really mean when we make essentialist claims. I argue that Fine’s arguments fail to strike a decisive blow, and I suggest a new interpretation of the debate that shows why Fine’s arguments fall short of achieving their goal.

In a recent paper on ‘The Many as One’, Lewis A. Kornhauser and Lawrence G. Sager look at an issue that we take to be of great importance in political theory. How far should groups in public life try to speak with one voice, and act with one mind? How far should public groups try to display what Ronald Dworkin calls integrity? We do not expect the many on the market to be integrated in this sense. But should we expect (...) integration among the many in the legislature, for example, or among the many on the courts? We agree with Kornhauser and Sager about a number of their claims but think that they miss out on important detail and do not achieve a fully general perspective on the issues raised. Our own contribution is in three sections. We address, first, the nature of the integrity challenge; second, the range of cases in which the challenge arises; and third, the question of whether public groups should be designed and required to meet that challenge. (shrink)

Is it coherent to suppose that in order to hold a belief responsibly, one must recognize something else as a reason for it? This paper addresses this question by focusing on so-called "Inferential Internalist" principles, that is principles of the following form: in order for one to have positive epistemic status Ø in virtue of believing P on the basis of R, one must believe that R evidentially supports P, and one must have positive epistemic status Ø in relation to (...) that latter belief as well. While such principles and their close relatives figure centrally in a wide variety of recent epistemological discussions, there is confusion in the literature about what, precisely, Inferential Internalism commits one to and whether it is so much as coherent. This paper articulates a broader framework for understanding the notion of epistemic responsibility, motivates Inferential Internalism on the basis of considerations about the basing relation, epistemic responsibility, and parallels with practical deliberation, defends Inferential Internalism against charges of incoherence leveled by James Van Cleve and Paul Boghossian, and shows that contrary to a currently widespread view, Inferential Internalism is coherent even if foundationalism and the a priori are rejected. The paper closes with a preliminary argument for an affirmative answer to the initiating question about the requirements of epistemic responsibility. (shrink)

Charles Peirce's diagrammatic logic — the Existential Graphs — is presented as a tool for illuminating how we know necessity, in answer to Benacerraf's famous challenge that most ‘semantics for mathematics’ do not ‘fit an acceptable epistemology’. It is suggested that necessary reasoning is in essence a recognition that a certain structure has the particular structure that it has. This means that, contra Hume and his contemporary heirs, necessity is observable. One just needs to pay attention, not merely to individual (...) things but to how those things are related in larger structures, certain aspects of which relations force certain other aspects to be a certain way. (shrink)

The issue of the justification of the laws of logic has been under discussion since the end of the nineteenth century. However, in many works devoted to this problem Ajdukiewicz’s achievements are left unmentioned. It can be shown that in certain periods of the development of his views, he tried to present various attempts at solving the problem of the justification of the laws of logic.

It is tempting to think that multi premise closure creates a special class of paradoxes having to do with the accumulation of risks, and that these paradoxes could be escaped by rejecting the principle, while still retaining single premise closure. I argue that single premise deduction is also susceptible to risks. I show that what I take to be the strongest argument for rejecting multi premise closure is also an argument for rejecting single premise closure. Because of the symmetry between (...) the principles, they come as a package: either both will have to be rejected or both will have to be revised. (shrink)

Continuing the conversation between Achilles and the tortoise begun by Carroll, this paper proves that, in a supertask context, there are free actions (in general, contingent states of affairs) that can be predicted by means of purely logical reasons.

Mathematics is a critical part of much scientific research. Physics in particular weaves math extensively into its instruction beginning in high school. Despite much research on the learning of both physics and math, the problem of how to effectively include math in physics in a way that reaches most students remains unsolved. In this paper, we suggest that a fundamental issue has received insufficient exploration: the fact that in science, we don’t just use math, we make meaning with it in (...) a different way than mathematicians do. In this reflective essay, we explore math as a language and consider the language of math in physics through the lens of cognitive linguistics. We begin by offering a number of examples that show how the use of math in physics differs from the use of math as typically found in math classes. We then explore basic concepts in cognitive semantics to show how humans make meaning with language in general. The critical elements are the roles of embodied cognition and interpretation in context. Then, we show how a theoretical framework commonly used in physics education research, resources, is coherent with and extends the ideas of cognitive semantics by connecting embodiment to phenomenological primitives and contextual interpretation to the dynamics of meaning-making with conceptual resources, epistemological resources, and affect. We present these ideas with illustrative case studies of students working on physics problems with math and demonstrate the dynamical nature of student reasoning with math in physics. We conclude with some thoughts about the implications for instruction. (shrink)

The linguistic theory of the logical A Priori: is it obsolete In holistic interpretations, the logical truths are considered as continuous with empirical science: they are revisable, a posteriori, though very near to the centre of our web of belief. In this paper, we consider the merits and demerits of this approach, and we propose that it is necessary to revaluate holistic philosophies of logic. Some arguments are put forward which point in favour of the logical empiricists’ theory of logical (...) truth. We argue (following Hartry Field) that the concept of “correlation between logical facts and logical beliefs” (which is at the heart of the holistic theory) is inconsistent. Finally, we concentrate on the principle of contradiction and argue (following Manley Thompson) that this principle is fundamental for meaning, truth, and thinking. This thesis is derived from considerations on the nature of intentionality. (shrink)

Picturing is a poorly understood element of Sellars’s philosophical project. We diagnose the problem with picturing as follows: on the one hand, it seems that it must be connected with action in order for it to do its job. On the other hand, the representational states of a picturing system are characterized in descriptive and seemingly static terms. How can static terms be connected with action? To solve this problem, we adopt a concept from recent work in Sellarsian metaethics: the (...) idea of a material practical inference, which (we argue) features centrally in how we picture. The key distinction is that the picturing of nonhuman animals involves only Humean material practical inference, in which representational states are corrected only by feedback from the environment and not from discursive interactions. The resulting view shows that Sellars’s contributions to practical philosophy (especially theory of action and metaethics) cannot be separated from his contributions to philosophy of mind, language, and cognitive science. Further, the view makes it clear that picturing is neither a version of the Given, nor is it a fifth wheel to inferential role in explaining representation, but is essential to Sellars’s model of how animals—including humans—represent their environment. (shrink)

Normativity involves two kinds of relation. On the one hand, there is the relation of being a reason for. This is a relation between a fact and an attitude. On the other hand, there are relations specified by requirements of rationality. These are relations among a person's attitudes, viewed in abstraction from the reasons for them. I ask how the normativity of rationality—the sense in which we ‘ought’ to comply with requirements of rationality—is related to the normativity of reasons—the sense (...) in which we ‘ought’ to have the attitudes what we have conclusive reason to have. The normativity of rationality is not straightforwardly that of reasons, I argue; there are no reasons to comply with rational requirements in general. First, this would lead to ‘bootstrapping’, because, contrary to the claims of John Broome, not all rational requirements have ‘wide scope’. Second, it is unclear what such reasons to be rational might be. Finally, we typically do not, and in many cases could not, treat rational requirements as reasons. Instead, I suggest, rationality is only apparently normative, and the normativity that it appears to have is that of reasons. According to this ‘Transparency Account’, rational requirements govern our responses to our beliefs about reasons. The normative ‘pressure’ that we feel, when rational requirements apply to us, derives from these beliefs: from the reasons that, as it seems to us, we have. (shrink)

This paper aims to shed light on the broader significance of Frege’s logicism against the background of discussing and comparing Wittgenstein’s ‘showing/saying’-distinction with Brandom’s idiom of logic as the enterprise of making the implicit rules of our linguistic practices explicit. The main thesis of this paper is that the problem of Frege’s logicism lies deeper than in its inconsistency : it lies in the basic idea that in arithmetic one can, and should, express everything that is implicitly presupposed so that (...) nothing is left unsaid. This, in fact, is the target of Wittgenstein’s critique. Rather than the Tractatus, with its claim that logicism attempts to say something that can only be shown, it is the Philosophical Investigations, with its argument by regress against the thesis that every rule which one can follow must be of an explicit nature, that is of real significance here. (shrink)

We raise an issue of circularity in the argument for the completeness of first-order logic. An analysis of the problem sheds light on the development of mathematics, and suggests other possible directions for foundational research.

I argue that logical understanding is not propositional knowledgebut is rather a species of practical knowledge. I further arguethat given the best explanation of logical understanding someversion or another of inferential role semantics must be the correct account of the determinants of logical content.

My purpose in this essay is to clarify the notion of explanation by computer simulation in artificial intelligence and cognitive science. My contention is that computer simulation may be understood as providing two different kinds of explanation, which makes the notion of explanation by computer simulation ambiguous. In order to show this, I shall draw a distinction between two possible ways of understanding the notion of simulation, depending on how one views the relation in which a computing system that performs (...) a cognitive task stands to the program that the system runs while performing that task. Next, I shall suggest that the kind of explanation that results from simulation is radically different in each case. In order to illustrate the difference, I will point out some prima facie methodological difficulties that need to be addressed in order to ensure that simulation plays a legitimate explanatory role in cognitive science, and I shall emphasize how those difficulties are very different depending on the notion of explanation involved. (shrink)

What is a bias? Standard philosophical views of both implicit and explicit bias focus this question on the representations one harbours, for example, stereotypes or implicit attitudes, rather than the ways in which those representations are manipulated. I call this approach representationalism. In this paper, I argue that representationalism taken as a general theory of psychological social bias is a mistake, because it conceptualizes bias in ways that do not fully capture the phenomenon. Crucially, this view fails to capture a (...) heretofore neglected possibility of bias, one that influences an individual’s beliefs about or actions toward others, but is, nevertheless, nowhere represented in that individual’s cognitive repertoire. In place of representationalism, I develop a functional account of psychological social bias which characterizes it as a mental entity that takes propositional mental states as inputs and returns propositional mental states as outputs in a way that instantiates social-kind inductions. This functional characterization leaves open which mental states and processes bridge the gap between the inputs and outputs, ultimately highlighting the diversity of candidates that can serve this role. (shrink)

Understanding has received growing interest from epistemologists in recent years, but no consensus regarding its epistemic properties has yet been reached. This paper extracts, but also rejects, candidates of epistemic properties for construing an epistemological model of understanding from the writings of epistemologists participating in the current discussion surrounding that state. On the basis of these results, a suggestion is put forward according to which understanding is a non-basic epistemic state of warrant rather than knowledge. It is argued that this (...) move provides a satisfactory conciliatory answer to the central question whether understanding is a factive epistemic state. Some differences between understanding and knowledge are recorded along the way: for instance, that in contrast to knowledge, understanding does not require belief and that, even though neither knowledge nor understanding iterates, so that a subject can both know without knowing that she knows, as well as understanding without understanding that she understands, the reasons for the failure is different. (shrink)

In this essay we argue that reasoning can sometimes generate epistemic justification, rather than merely transmitting justification that the subject already possesses to new beliefs. We also suggest a way to account for it in terms of the relationship between epistemic normative requirements, justification and cognitive capacities.

The uses and interpretation of reductio ad absurdum argumentation in mathematical proof and discovery are examined, illustrated with elementary and progressively sophisticated examples, and explained. Against Arthur Schopenhauer’s objections, reductio reasoning is defended as a method of uncovering new mathematical truths, and not merely of confirming independently grasped mathematical intuitions. The application of reductio argument is contrasted with purely mechanical brute algorithmic inferences as an art requiring skill and intelligent intervention in the choice of hypotheses and attribution of contradictions deduced (...) to a particular assumption in a contradiction’s derivation base within a reductio proof structure. (shrink)

There are two central kinds of epistemological mistakes: believing things you shouldn’t, and failing to believe things that you should. The knowledge-first program offers a canonical explanation for the former: if you believe something without knowing it, you violate the norm to believe only that which you know. But the explanation does not extend in any plausible way to a story about what’s wrong with suspending judgment when one ought to believe. In this paper I explore prospects for a knowledge-centering (...) account of positive epistemic norms that describe epistemic duties to believe. (shrink)

The justificatory force of empirical reasoning always depends upon the existence of some synthetic, a priori justification. The reasoner must begin with justified, substantive constraints on both the prior probability of the conclusion and certain conditional probabilities; otherwise, all possible degrees of belief in the conclusion are left open given the premises. Such constraints cannot in general be empirically justified, on pain of infinite regress. Nor does subjective Bayesianism offer a way out for the empiricist. Despite often-cited convergence theorems, subjective (...) Bayesians cannot hold that any empirical hypothesis is ever objectively justified in the relevant sense. Rationalism is thus the only alternative to an implausible skepticism. (shrink)

The paper argues for a version of the Guise of the Good thesis, namely the claim that if someone acts as the result of practical reasoning, then she takes her premises to jointly provide a sufficient and undefeated reason for her action. I argue for this by showing, first, that it is an application of Boghossian's Taking Condition on inference to practical reasoning and, second, that the motivations for the Taking Condition for theoretical reasoning carry over to practical reasoning. I (...) end by arguing that this version of the Guise of the Good withstands standard objections. (shrink)

It is often assumed that neo-Aristotelian virtue ethics postulates an obligation to be a good human being and that it derives further obligations from this idea. The paper argues that this assumption is false, at least for Philippa Foot’s view. Our argument blocks a widespread objection to Foot’s view, and it shows how virtue ethics in general can neutralize such worries.

In many actual arguments, the conclusion seems intuitively to follow from the premisses, even though we cannot show that it follows logically. The traditional approach to evaluating such arguments is to suppose that they have an unstated premiss whose explicit addition will produce an argument where the conclusion does follow logically. But there are good reasons for doubting that people so frequently leave the premisses of their arguments unstated. The inclination to suppose that they do stems from the belief that (...) the only way in which an argument's conclusion can follow definitely from its premisses is to follow logically. I argue that this belief is mistaken. I propose a revision of the current generic conception of logical consequence, and its variant specifications, to avoid the paradoxes of strict implication. The revised conception can then be naturally extended to include also what we might call 'enthymematic consequence'. This concept is a kind of consequence, whose properties merit investigation. (shrink)

In the first chapter of his Knowledge and Lotteries, John Hawthorne argues that thinkers do not ordinarily know lottery propositions. His arguments depend on claims about the intimate connections between knowledge and assertion, epistemic possibility, practical reasoning, and theoretical reasoning. In this paper, we cast doubt on the proposed connections. We also put forward an alternative picture of belief and reasoning. In particular, we argue that assertion is governed by a Gricean constraint that makes no reference to knowledge, and that (...) practical reasoning has more to do with rational degrees of belief than with states of knowledge. (shrink)

So-called 'Frege cases' pose a challenge for anyone who would hope to treat the contents of beliefs (and similar mental states) as Russellian propositions: It is then impossible to explain people's behavior in Frege cases without invoking non-intentional features of their mental states, and doing that seems to undermine the intentionality of psychological explanation. In the present paper, I develop this sort of objection in what seems to me to be its strongest form, but then offer a response to it. (...) I grant that psychological explanation must invoke non-intentional features of mental states, but it is of crucial importance which such features must be referenced. -/- It emerges from a careful reading of Frege's own view that we need only invoke what I call 'formal' relations between mental states. I then claim that referencing such 'formal' relations within psychological explanation does not undermine its intentionality in the way that invoking, say, neurological features would. The central worry about this view is that either (a) 'formal' relations bring narrow content in through back door or (b) 'formal' relations end up doing all the explanatory work. Various forms of each worry are discussed. The crucial point, ultimately, is that the present strategy for responding to Frege cases is not available either to the 'psycho-Fregean', who would identify the content of a belief with its truth-value, nor even to someone who would identify the content of a belief with a set of possible worlds. It requires the sort of rich semantic structure that is distinctive of Russellian propositions. There is therefore no reason to suppose that the invocation of 'formal' relations threatens to deprive content of any work to do. (shrink)

The idea of the uniformity of nature, as a solution to the problem of induction, has at least two contemporary versions: natural kinds and natural necessity. Then there are at least three alternative ontological ideas addressing the problem of induction. In this paper, I articulate how these ideas are used to justify the practice of inductive inference, and compare them, in terms of their applicability, to see whether each of them is preferred in addressing the problem of induction. Given the (...) variety of contexts in which inductive inferences are made, from natural science to social science and to everyday thinking, I suggest that no singular idea is absolutely preferred, and a proper strategy is probably to welcome the plurality of ideas helpful to induction, and to take pragmatic considerations into account, in order to judge in every single case. (shrink)

We argue that Hilary Putnam's pragmatism provides an epistemological perspective which can help us understand--and can positively inform--the development of informal logic.

What is it that makes someone wise, or one person wiser than another? I argue that wisdom consists in knowledge of how to live well, and that this knowledge of how to live well is constituted by various further kinds of knowledge. One concern for this view is that knowledge is not needed for wisdom but rather some state short of knowledge, such as having rational or justified beliefs about various topics. Another concern is that the emphasis on knowing how (...) to live well fails to do justice to the ancient tradition of ‘theoretical wisdom’. I address both of these concerns in filling out the account. (shrink)

Brandom’s inferentialism offers, in many ways, a radically new approach to old issues in semantics and the theory of intentionality. But, in one respect at least, it clings tenaciously to the mainstream philosophical tradition of the middle years of the twentieth century. Against the theory’s natural tendencies, Brandom aligns it with the ’linguistic turn’ that philosophy took in the middle of the last century by insisting, in the face of considerable opposing evidence, that intentionality is the preserve of those who (...) can offer and ask for reasons and thus of language users alone. In this paper, I argue that there is no good reason for giving inferentialism a linguistic twist, and that, in doing so, Brandom is forced to make claims which are implausible in themselves and lead him, in the attempt to mitigate them, to a number of doubtful expedients. (shrink)

Identifying the missing or unstated premisses of arguments is important, because their logical quality depends on them. Textbook authors regard enthymematic syllogisms (e.g., "Elvis is a man, so Elvis is mortal") as having an unstated premiss - the major premiss (e.g., "All men are mortal"). They are said to be such because these syllogisms become formally valid when the major premiss is added (i.e., it is a gap-filler). I argue that unstated major premises are not gap-fillers: they support a part (...) of the argument that is already given implicitly - the inference claim ("If the premisses are true then the conclusion is true"). As such, their logical status is the same as that of an unstated proposition that supports the minor premiss, which is not part of the argument. Therefore, the so-called "major premiss" is not an unstated premiss of the enthymeme. (shrink)

We seek means of distinguishing logical knowledge from other kinds of knowledge, especially mathematics. The attempt is restricted to classical two-valued logic and assumes that the basic notion in logic is the proposition. First, we explain the distinction between the parts and the moments of a whole, and theories of ?sortal terms?, two theories that will feature prominently. Second, we propose that logic comprises four ?momental sectors?: the propositional and the functional calculi, the calculus of asserted propositions, and rules for (...) (in)valid deduction, inference or substitution. Third, we elaborate on two neglected features of logic: the various modes of negating some part(s) of a proposition R, not only its ?external? negation not-R; and the assertion of R in the pair of propositions ?it is (un)true that R? belonging to the neglected logic of asserted propositions, which is usually left unstated. We also address the overlooked task of testing the asserted truth-value of R. Fourth, we locate logic among other foundational studies: set theory and other theories of collections, metamathematics, axiomatisation, definitions, model theory, and abstract and operator algebras. Fifth, we test this characterisation in two important contexts: the formulation of some logical paradoxes, especially the propositional ones; and indirect proof-methods, especially that by contradiction. The outcomes differ for asserted propositions from those for unasserted ones. Finally, we reflect upon self-referring self-reference, and on the relationships between logical and mathematical knowledge. A subject index is appended. (shrink)

In the wake of Frege's attack on psychologism and the subsequent influence of Logical Positivism, psychological considerations in philosophy came to be viewed with suspicion. Philosophical questions, especially epistemological ones, were viewed as 'logical' questions, and logic was sharply separated from psychology. Various efforts have been made of late to reconnect epistemology with psychology. But there is little agreement about how such connections should be made, and doubts about the place of psychology within epistemology are still much in evidence. It (...) therefore remains to be clarified just how such links should be established, and what impact they would have on the direction of epistemology. (shrink)

Wittgenstein's Tractatus is widely regarded as a masterpiece, a brilliant, if flawed attempt to achieve an ‘unassailable and definitive … final solution’ to a wide range of philosophical problems. Yet, in a 1931 notebook, Wittgenstein confesses: ‘I think there is some truth in my idea that I am really only reproductive in my thinking. I think I have never invented a line of thinking but that it was always provided for me by someone else’. This disarming self-assessment is, I believe (...) accurate. The Tractatus, despite making significant advances on the logical doctrines of Frege and Russell, is essentially a derivative work—Wittgenstein, as he elsewhere acknowledges, provided a fertile soil in which the original seeds of other peoples' thought grew in a unique way. In a play of mine, published in Philosophy (1999), Wittgenstein fails a tough viva on the Tractatus because he fails to properly support some of the weak arguments in the work and because of his inadequate acknowledgment of sources. The present paper further explores some of the antecedents of Wittgenstein's early views and answers some criticisms of the play. (shrink)

Epistemology has recently witnessed a number of efforts to rehabilitate rationalism, to defend the existence and importance of a priori knowledge or warrant construed as the product of rational insight or apprehension (Bealer 1987; Bigelow 1992; BonJour 1992, 1998; Burge 1998; Butchvarov 1970; Katz 1998; Plantinga 1993). This effort has sometimes been coupled with an attack on naturalistic epistemology, especially in BonJour 1994 and Katz 1998. Such coupling is not surprising, because naturalistic epistemology is often associated with thoroughgoing empiricism and (...) the rejection of the a priori. In this paper, however, I shall present a conception of naturalistic epistemology that is entirely compatible with a priori justification or knowledge. The resulting conception, I claim, gives us a better appreciation of the respective merits of the rational and the empirical, as well as a better understanding of how moderate epistemological naturalism comports, at least in principle, with moderate rationalism. This paper defends moderate rationalism; but it does not defend everything rationalists have often wanted, only what it is reasonable to grant them. (shrink)

If we use “introspection” just as a label for that essentially first-person way we have of knowing about our own mental states, then it’s pretty obvious that if there is such a thing as introspection, we know on that basis what we believe, and want, and intend, at least in many ordinary cases. I assume there is such a thing as introspection. So I think the hard question is how it works. But can you know that you know on the (...) basis of introspection? Well, that all depends on how introspection works. I present one account of how introspection works and argue that on that account, you can know that you know ordinary empirical things on the basis of introspection. As far as how we know about them is concerned, there’s no principled difference between the factive and non-factive mental states. (shrink)

El excepcionalismo de la lógica asume que la lógica tiene un estatus epistemológico privilegiado, es normativa y no es revisable. El antiexcepcionalismo, en cambio, rechaza ese carácter excepcional. Recientemente, se ha sugerido que el problema de la adopción de reglas lógicas es transversal a la discusión que se da entre excepcionalistas y antiexcepcionalistas. En este trabajo defiendo la tesis contraria. En particular, sostengo que, si el problema de la adopción de reglas es un problema central para la lógica como disciplina, (...) el antiexcepcionalismo debe ser incorrecto. En caso contrario, debe ser incorrecta la postura excepcionalista. Evalúo, además, consecuencias directas del análisis presente sobre la discusión en torno al monismo y el pluralismo de la lógica. (shrink)

I present an account of deterministic chance which builds upon the physico-mathematical approach to theorizing about deterministic chance known as 'the method of arbitrary functions'. This approach promisingly yields deterministic probabilities which align with what we take the chances to be---it tells us that there is approximately a 1/2 probability of a spun roulette wheel stopping on black, and approximately a 1/2 probability of a flipped coin landing heads up---but it requires some probabilistic materials to work with. I contend that (...) the right probabilistic materials are found in reasonable initial credence distributions. I note that, with some normative assumptions, the resulting account entails that deterministic chances obey a variant of Lewis's 'principal principle'. I additionally argue that deterministic chances, so understood, are capable of explaining long-run frequencies. (shrink)

This paper gives an account of Anderson and Belnap’s selection criteria for an adequate theory of entailment. The criteria are grouped into three categories: criteria pertaining to modality, those pertaining to relevance, and those related to expressive strength. The leitmotif of both this paper and its prequel is the relevant legitimacy of disjunctive syllogism. Relevant logics are commonly held to be paraconsistent logics. It is shown in this paper, however, that both E and R can be extended to explosive logics (...) which satisfy all of Anderson and Belnap’s selection criteria, provided the truth-constant known as the Ackermann constant is available. One of the selection criteria related to expressive strength is having an “enthymematic” conditional for which a deduction theorem holds. I argue that this allows for a new interpretation of Anderson and Belnap’s take on logical consequence, namely as committing them to pluralism about logical consequence. (shrink)

This paper argues that adopting a particular dialogical account of logical consequence quite directly gives rise to an interesting form of logical pluralism, the form of pluralism in question arising out of the requirement that deductive proofs be explanatory.

The exegesis of sacred rites in the Talmud is subject to a restriction on the iteration and composition of inference rules. In order to determine the scope and limits of that restriction, the sages of the Talmud deploy those very same inference rules. We present the remarkable features of this early use of self-reference to navigate logical constraints and uncover the hidden complexity behind the sages? arguments. Appendix 11 contains a translation of the relevant sugya. 1Hebrew and Aramaic transliteration approximates (...) traditional Sephardic pronunciation, which is closer to academic standard transliteration than the various Ashkenazic pronunciations, yet is legible. Specific references follow the convention of folio (number), side (a or b), number of lines from the top or (if negative) bottom of the page. (shrink)

A new kind of debate about the normative error theory has emerged. Whereas longstanding debates have fixed on the error theory’s plausibility, this new debate concerns the theory’s believability. Bart Streumer is the chief proponent of the error theory’s unbelievability. In this brief essay, we argue that Streumer’s argument prevails against extant critiques, and then press a criticism of our own.

This essay accounts for the notion of _Lebensform_ by assigning it a _logical _role in Wittgenstein’s later philosophy. Wittgenstein’s additions of the notion to his manuscripts of the _PI_ occurred during the initial drafting of the book 1936-7, after he abandoned his effort to revise _The Brown Book_. It is argued that this constituted a substantive step forward in his attitude toward the notion of simplicity as it figures within the notion of logical analysis. Next, a reconstruction of his later (...) remarks on _Lebensformen_ is offered which factors in his reading of Alan Turing’s “On computable numbers, with an application to the _Entscheidungsproblem_“, as well as his discussions with Turing 1937-1939. An interpretation of the five occurrences of _Lebensform_ in the PI is then given in terms of a logical “regression” to _Lebensform_ as a fundamental notion. This regression characterizes Wittgenstein’s mature answer to the question, “What is the nature of the logical?”. (shrink)