ABSTRACT Topos quantum theory is standardly portrayed as a kind of ‘neo-realist’ reformulation of quantum mechanics.1 1 In this article, I study the extent to which TQT can really be characterized as a realist formulation of the theory, and examine the question of whether the kind of realism that is provided by TQT satisfies the philosophical motivations that are usually associated with the search for a realist reformulation of quantum theory. Specifically, I show that the notion of the quantum state (...) is problematic for those who view TQT as a realist reformulation of quantum theory. 1Introduction 2Topos Quantum Theory 2.1Phase space 2.2Hilbert space 2.3Beyond Hilbert space 2.4Defining realism 2.5The spectral presheaf 2.6The logic of topos quantum theory 3Interpreting States in Topos Quantum Theory 4Interpreting Truth Values and Clopen Subobjects in Topos Quantum Theory 4.1Interpreting the truth values 4.2Interpreting Subcl 5Neo-realism 5.1The covariant approach 6Conclusion. (shrink)

En este artículo, analizo las principales respuestas que se han dado al argumento finitista de Etchemendy, y muestro que ninguna de ellas es exitosa. Primero, describo y critico las propuestas que intentan resolverlo apelando a consideraciones modales. Estas soluciones fallan porque presuponen un finitismo demasiado débil, donde se acepta la existencia de infinitos conjuntos o de mundos posibles con infinitos objetos. Pero hay versiones más fuertes del finitismo que reintroducen el problema. Luego considero las soluciones que apelan a categorías semánticas. (...) Una de ellas categoriza incorrectamente este problema como un desacuerdo sobre el significado de los cuantificadores. La otra solución falla porque, si fuera tomada en serio, tendría efectos muy nocivos para la lógica en general. Finalmente argumento que la mejor solución es morder la bala y aceptar que la lógica no debería ser fuertemente independiente de algunos asuntos que tradicionalmente fueron considerados como 'extralógicos'. In this paper, I analyze the main replies that have been given to Etchemendy's finitist argument, and I show that none of them is successful. First, I describe and criticize the proposals that try to solve the problem by appealing to modal considerations. These solutions fail because they presuppose a very weak finitism, where the existence of infinitely many sets, or possible words with infinitely many objects, is accepted. But there are stronger versions of finitism that reintroduce the problem. Then I consider the solutions which appeal to semantical categories. One of them incorrectly categorizes the problem as a disagreement in the meaning of the quantifiers. The other fails because, if taken seriously, it would have harmful effects on logic in general. Finally I argue that the best solution is to bite the bullet and accept that logic shouldn't be strongly independent from some issues which were traditionally considered as 'extra-logical'. (shrink)

This paper defends the thesis that counterfactuals are strict conditionals. Its purpose is to show that there is a coherent view according to which counterfactuals are strict conditionals whose antecedent is stated elliptically. Section 1 introduces the view. Section 2 outlines a response to the main argument against the thesis that counterfactuals are strict conditionals. Section 3 compares the view with a proposal due to Aqvist, which may be regarded as its direct predecessor. Sections 4 and 5 explain how the (...) view di ers from the theories of counterfactuals advocated by Stalnaker and Lewis, and from some contextualist strict conditional accounts of counterfactuals that have emerged recently. Finally, section 6 addresses the thorny issue of disjunctive antecedents. (shrink)

This paper is concerned with vagueness in language, its relation to logico-philosophical questions on the one hand, and to so-called syncategorematic terms and their linguistic use on the other hand. It attempts to show that it is not language itself which is vague but rather the way we use it.

Critical notice of Richard Gaskin's "The Unity of the Proposition" (OUP 2008).

Michael Beaney ha sugerido recientemente que la distinción fregeana entre sentido y referencia fue propuesta para resolver la famosa paradoja del análisis. Casi diez años antes, Michael Dummett ya insistia en que Frege fue uno de los prirneros en buscar una soluci6n satisfactoria de esta paradoja. En esre articulo, discuto algunas sugerencias de Beaney y Dummett de cómo resolver la paradoja al estilo fregeano y tarnbién sus propias contribuciones no fregeanas al debate en torno de la corrección y de la (...) informatividad del análisis. Mi intención en esta discusión es mostrar que ninguna de ellas funciona. Concluyo con una propuesta de inspiración witttgensteiniana --el enfoque de los conceptos abiertos- para apoyar la idea de que la apelación a contertidos abiertos es la rnejor rnanera de disolver la paradoja.Michael Beaney has recently suggested that the Fregean distinction between sense and reference was proposed to solve the famous paradox of analysis. Not as recently, Michael Dummett has insisted that Frege was one of the first to look for a satisfactory solution to this paradox. In this paper, I discuss Beanry’s and Dummett’s various suggestions for solving the paradox in a Fregean style as well as their own non Fregean contributions to the debate around analysis’s correction and informativeness. My intention in this discussion is to show that none of them works. I conclude with a proposal inspired by Wittgenstein’s later work -the open concepts’ proposal- designed to support the idea that the appeal to open contents is the best way to dissolve the paradox. (shrink)

It might be expected that it would suffice for the entry for “moral anti-realism” to contain only some links to other entries in this encyclopedia. It could contain a link to “moral realism” and stipulate the negation of the view there described. Alternatively, it could have links to the entries “anti-realism” and “morality” and could stipulate the conjunction of the materials contained therein. The fact that neither of these approaches would be adequate—and, more strikingly, that following the two procedures would (...) yield substantively non-equivalent results—reveals the contentious and unsettled nature of the topic. -/- “Anti-realism,” “non-realism,” and “irrealism” may for most purposes be treated as synonymous. Occasionally, distinctions have been suggested for local pedagogic reasons (see, e.g., Wright 1988a; Dreier 2004), but no such distinction has generally taken hold. (“Quasi-realism” denotes something very different, to be discussed in the supplement Projectivism and quasi-realism below.) All three terms are to be defined in opposition to realism, but since there is no consensus on how “realism” is to be understood, “anti-realism” fares no better. Crispin Wright (1992: 1) comments that “if there ever was a consensus of understanding about ‘realism’, as a philosophical term of art, it has undoubtedly been fragmented by the pressures exerted by the various debates—so much so that a philosopher who asserts that she is a realist about theoretical science, for example, or ethics, has probably, for most philosophical audiences, accomplished little more than to clear her throat.” This entry doesn't purport to do justice to the intricacy and subtlety of the topic of realism; it should be acknowledged at the outset that the fragmentation of which Wright speaks renders it unlikely that the label “moral anti-realism” even succeeds in picking out a definite position. Yet perhaps we can at least make an advance on clearing our throats. (shrink)

Questions concerning the nature of representation and what representations are about have been a staple of Western philosophy since Aristotle. Recently, these same questions have begun to concern neuroscientists, who have developed new techniques and theories for understanding how the locus of neurobiological representation, the brain, operates. My dissertation draws on philosophy and neuroscience to develop a novel theory of representational content.

Responding to the paradox of inference and the related problems in philosophy of logic, this paper argues for the necessity of distinguishing between two different objects of justification: logica utens and logica docens. Then, equipped with Peirce’s critical common-sensist conception of logica utens and his classification of sciences, I propose a diagnosis of and a solution to the problem of justification of logic. I argue that this alternative approach successfully avoids circularity in which most attempts in philosophy of logic have (...) been inescapably trapped. I also anticipate and respond to possible objections to taking a Peircean turn in justifying logic. (shrink)

A remarkable thing about natural language is that we can use it to share our beliefs and thoughts about the world with other speakers of our language. In cases of successful communication, beliefs seem to be transferred from speakers to hearers by means of the hearer recovering the contents of the speaker’s utterances. This is so natural to us that we take it for granted in our everyday life, and rarely stop to think about how it's is possible. Nevertheless, it's (...) a phenomenon that calls for explanation. It is natural to expect that natural language semantics has a key explanatory role to play here. In order to understand this role, we must relate the semantic values assigned to sentences by semantic theory with the content of our speech acts. The simplest possible relation would be identity; the meaning of a sentence is simply the belief expressed by an assertion of the sentence in a given context of utterance. However, a number of problem cases in the literature suggest that this cannot be the case. This dissertation offers a critical assessment of the arguments for distinguishing the semantic value of a sentence from it's so called assertoric content, focusing on problems arising from the analysis of tense and temporal expressions. I conclude that they are indeed distinct, and offer a constructive account of how they must be related in order to allow for an explanation of communicative success. (shrink)

I defend the view that our ontology divides into categories, each with its own canonical way of identifying and distinguishing the objects it encompasses. For instance, I argue that natural numbers are identified and distinguished by their positions in the number sequence, and physical bodies, by facts having to do with spatiotemporal continuity. I also argue that objects belonging to different categories are ipso facto distinct. My arguments are based on an analysis of reference, which ascribes to reference a richer (...) structure than it is normally taken to have. (shrink)

Logic ought to guide our thinking. It is better, more rational, more intelligent to think logically than to think illogically. Illogical thought leads to bad judgment and error. In any case, if logic had no role to play as a guide to thought, why should we bother with it?The somewhat naïve opinions of the previous paragraph are subject to attack from many sides. It may be objected that an activity does not count as thinking at all unless it is at (...) least minimally logical, so logic is constitutive of thought rather than a guide to it. Or it may be objected that whereas logic describes a system of timeless relations between propositions, thinking is a dynamic process involving revisions, and so could not use a merely static guide. Or again the objection may be that there is no such thing as logic, only a whole variety of different logics, not all of which could possibly be good guides. (shrink)

In this paper I provide a theory of the speech act of assertion according to which assertion is a species of joint action. In doing so I rely on a theory of joint action developed in more detail elsewhere. Here we need to distinguish between the genus, joint action, and an important species of joint action, namely, what I call joint epistemic action. In the case of the latter, but not necessarily the former, participating agents have epistemic goals, e.g., the (...) acquisition of knowledge. It is joint epistemic action that assertion is a species of. (shrink)

A comparison is given between two conditions used to define logical constants: Belnap's uniqueness and Hacking's deducibility of identicals. It is shown that, in spite of some surface similarities, there is a deep difference between them. On the one hand, deducibility of identicals turns out to be a weaker and less demanding condition than uniqueness. On the other hand, deducibility of identicals is shown to be more faithful to the inferentialist perspective, permitting definition of genuinely proof-theoretical concepts. This kind of (...) analysis is driven by exploiting the Curry–Howard correspondence. In particular, deducibility of identicals is shown to correspond to the computational property of eta expansion, which is essential in the characterization of propositional identity. (shrink)

Platonism about mathematics (or mathematical platonism) isthe metaphysical view that there are abstract mathematical objectswhose existence is independent of us and our language, thought, andpractices. Just as electrons and planets exist independently of us, sodo numbers and sets. And just as statements about electrons and planetsare made true or false by the objects with which they are concerned andthese objects' perfectly objective properties, so are statements aboutnumbers and sets. Mathematical truths are therefore discovered, notinvented., Existence. There are mathematical objects.

Is the truthmaker principle a development of the correspondence theory of truth? So Armstrong introduced the truthmaker principle to us, but Lewis (2001. Forget about the ‘correspondence theory of truth’. Analysis 61: 275–80.) influentially argued that it is neither a correspondence theory nor a theory of truth. But the truthmaker principle can be correctly understood as a development of the correspondence theory if it’s conceived as incorporating the insight that truth is a relation between truth-bearers and something worldly. And we (...) strengthen rather than weaken the plausibility of the truthmaker principle if we conceive of truth as performing a substantial rather than deflationary role in the truthmaker principle. (shrink)

The verification of a sentence against a visual display in experimental conditions reveals a procedure that is driven solely by the properties of the linguistic input and not by the properties of the context (the set-up of the visual display) or extra-linguistic cognition (operations executed to obtain the truth value). This procedure, according to the Interface Transparency Thesis (ITT) (Lidz et al. in Nat Lang Semant 19(3):227–256, 2011), represents the meaning of an expression at the interface with the ‘conceptual-intentional’ system (...) (Chomsky in The minimalist program. MIT Press, Cambridge, 1995). My experiments provide support for the ITT by replicating in Polish and in Bulgarian the findings of Lidz et al. (Nat Lang Semant 19(3):227–256, 2011) for the English quantifier most. We also obtain new evidence that participants are prompted to switch between verification procedures by a change in the linguistic input (a different superlative quantifier entailed by most), but not by a change in the visual input. Thus, the motivation for the subconscious switch in procedures is not to maximize efficiency. Participants use the procedure associated with each quantifier, and in effect, the same display is verified differently depending on which information the visual system is instructed to use by the semantic representation of the sentence. (shrink)

This paper explores the relationships between Davidson's indeterminacy of interpretation thesis and two semantic properties of sentences that have come to be recognized recently, namely semantic incompleteness and semantic indecision.1 More specifically, I will examine what the indeterminacy thesis entails for sentences of the form 'By sentence S (or word w), agent A means that m' and 'Agent A believes that p.' My primary goal is to shed light on the indeterminacy thesis and its consequences. I will distinguish two kinds (...) of indeterminacy that have very different sources and very different consequences. But this does not purport to be an exhaustive study: there may well be other forms of indeterminacy that this .. (shrink)

In Hard Truths Elijah Millgram argues that ‘partial truth’ is pervasive and for that reason bivalence 1 may rarely be assumed. As classical logic assumes bivalence, and inferences from partial truths to partial truths are central to our thinking, classical logic rarely has application, the argument continues. And so we must develop an account of inference from partial truths to partial truths; as well, our metaphysics must be revised. While the novel positions of Hard Truths 2 raise many interesting challenges, (...) my focus is limited to offering an alternative to Millgram’s account of predication and to exploring some issues raised by his appeal to ‘fit’ in his definitions of truth and partial truth. 1. Introduction to partial truth Millgram defines truth and partial truth in terms of fit, as follows: Advancing a claim as fully true demands complete fit; assessing a claim as partially true allows for slack … but only so much of it. Claims are said to completely fit, slackly fit or not fit, the world, in §6.3. But, the word ‘fit’ is first introduced in §1.2, and it is experience or proto-experience, that fits into moulds provided by claims, thoughts, sentences and predicates. I won’t dwell on which fits what, 3 but on the notion of a ‘complete fit’ and the contrast with a ‘slack fit’; this discussion leads me to ponder the clarity and implications of appealing to these notions in definitions like the above. Millgram’s explanation of fit comes in the context of his account of predication, according to which, most predicates do not quite apply. It’s this that is primarily responsible for his promotion of partial truth. I sketch an alternative account of language whereby predicates do apply because language has come to life as a constituent of the things we do: …. (shrink)

In this paper the informativeness account of assertion (Pagin in Assertion. Oxford University Press, Oxford, 2011) is extended to account for inference. I characterize the conclusion of an inference as asserted conditionally on the assertion of the premises. This gives a notion of conditional assertion (distinct from the standard notion related to the affirmation of conditionals). Validity and logical validity of an inference is characterized in terms of the application of method that preserves informativeness, and contrasted with consequence and logical (...) consequence, that is defined in terms of truth preservation. The proposed account is compared with that of Prawitz (Logica yearbook 2008, pp. 175-192. College Publications, London, 2009). (shrink)

Philosophers have responded to McTaggart’s famous argument for the unreality of time in a variety of ways. Some of those responses are not easy to evaluate, since they involve, for example, sometimes murky questions concerning whether a certain infinite regress is or is not vicious. In this paper I set out a response that has not, I think, been advanced by any other author, and which, if successful, is absolutely clear-cut. The basic idea is simply that a tensed approach to (...) time can avoid McTaggart’s contradiction, and can also avoid any regress, vicious or otherwise, by specifying the times at which events have different tensed properties in a tenseless fashion — namely, by using dates. This answer to McTaggart’s argument is, however, open to four important objections. The first objection is that my answer to the second part of McTaggart’s argument is incompatible with something that McTaggart takes himself to have proved in the first part of his argument — the claim, namely, that “there can be no change unless some propositions are sometimes true and sometimes false.” The second objection is that the sentences that I claim can be used to specify when an event has a given tensed property do not in fact do so, since they turn out to be purely tenseless sentences. The third objection is that the sentences in question make use of tenseless verbs, and that it is not in fact possible to make sense of such verbs. The fourth and final objection is that it is not really possible to specify, in tenseless terms, when an event has a given tensed property, since dates have to be analyzed using the relation of temporal priority, and that relation, in turn, must be analyzed in terms of the tensed properties of pastness, presentness and futurity, so that the purportedly tenseless specification is implicitly tensed. I argue, however, that none of these four objections can be sustained. (shrink)

I argue that the implementation of theDummettian program of an ``anti-realist'' semanticsrequires quite different conceptions of the technicalmeaning-theoretic terms used than those presupposed byDummett. Starting from obvious incoherences in anattempt to conceive truth conditions as assertibilityconditions, I argue that for anti-realist purposesnon-epistemic semantic notions are more usefully kept apart from epistemic ones rather than beingreduced to them. Embedding an anti-realist theory ofmeaning in Martin-Löf's Intuitionistic Type Theory(ITT) takes care, however, of many notorious problemsthat have arisen in trying to specify suitableintuitionistic (...) notions of semantic value,truth-conditions, and validity, taking into accountthe so-called ``defeasibility of evidence'' forassertions in empirical discourses. (shrink)

In this paper, we offer a theory of the role of the nominal in complex demonstrative expressions, such as 'this dog' or 'that glove with a hole in it'.

ABSTRACT What do we disagree about when we disagree about logic? On the face of it, classical and nonclassical logicians disagree about the laws of logic and the nature of logical properties. Yet, sometimes the parties are accused of talking past each other. The worry is that if the parties to the dispute do not mean the same thing with ‘if’, ‘or’, and ‘not’, they fail to have genuine disagreement about the laws in question. After the work of Quine, this (...) objection against genuine disagreement about logic has been called the meaning-variance thesis. We argue that the meaning-variance thesis can be endorsed without blocking genuine disagreement. In fact, even the type of revisionism and nonapriorism championed by Quine turns out to be compatible with meaning-variance. (shrink)

When I studied the Scriptures then I did not feel as I am writing about them now. They seemed to me unworthy of comparison with the grand style of Cicero (Augustine, III, 5).As for the absurdities which used to offend me in Scripture, … I now looked for their meanings in the depth of mystery (sacramentorum) (Augustine, VI, 5).

How do we inferentially unify separately acquired empirical information into a single comprehensive picture of the lives of persistent particulars? This paper argues that hidden in such inferences is a Fregean puzzle that can only be solved by individuating our demonstratives thoughts in terms of object-dependent Fregean Senses. I begin by characterizing some constraints on a non-skeptical account of our inferential unification of empirical information. I then go on to show that traditional Fregean views of Sense cannot explain the rationality (...) of such inferences; the consequence of which would be widespread skepticism concerning fundamental aspects of our empirical worldview. I show how the theory of object-dependent Senses can account for the rationality of the puzzling inferences. Lastly, I consider the alternative that we abandon a Fregean explanation of the rationality of inferences. While not fully dismissing that option, I briefly raise, what I take to be, a daunting challenge that uniquely faces non-Fregean views of rational inference. (shrink)

Anti-realistic conceptions of truth and falsity are usually epistemic or inferentialist. Truth is regarded as knowability, or provability, or warranted assertability, and the falsity of a statement or formula is identified with the truth of its negation. In this paper, a non-inferentialist but nevertheless anti-realistic conception of logical truth and falsity is developed. According to this conception, a formula (or a declarative sentence) A is logically true if and only if no matter what is told about what is told about (...) the truth or falsity of atomic sentences, A always receives the top-element of a certain partial order on non-ontic semantic values as its value. The ordering in question is a told-true order. Analogously, a formula A is logically false just in case no matter what is told about what is told about the truth or falsity of atomic sentences, A always receives the top-element of a certain told-false order as its value. Here, truth and falsity are pari passu , and it is the treatment of truth and falsity as independent of each other that leads to an informational interpretation of these notions in terms of a certain kind of higher-level information. (shrink)

Donald Davidson brought to our attention deviant causal chains as a problem for causal theories of action. Consider Davidson's own example: " A climber might want to rid himself of the weight and danger of holding another man on a rope, and he might know that by loosening his hold on the rope he could rid himself of the weight and danger. This belief and want might so unnerve him as to cause him to loosen his hold, and yet it (...) might be the case that he never chose to loosen his hold, nor did he do it intentionally. " The loosening of the hold on the rope is an action, according to a simple causal theory of action earlier developed by Davidson , if we can describe it in a way that renders it intentional under that description. Is there a way of describing the climber's loosening of his hold of the rope as intentional? Did he intentionally loosen his hold? Well, his loosening his hold is both rationalized and explained causally with reference to the beliefs and desires held by the climber. But there seems to be something wrong with the causal chain.Is there a simple fix? Could we not say that even if the loosening of the hold on the rope is caused by a desire held by the climber it is not caused by any proximate desire of the climber ? Or, to give a new twist to this well-known argument, could we not say that the loosening of the hold on the rope is not caused in a way that is responsive to the desire? This latter idea has recently been suggested by Markus E. Schlosser as a simple solution to the …. (shrink)

Scientific realism at least in large measure reflects the conviction that physics limns the true nature of reality; that it is the right metaphysical picture of things. This conviction is in turn a product of the failure of positivism's attempt to expunge metaphysics from the corpus of philosophically respectable activities. Since natural science is objective knowledge of the worldpar excellencepost-positivists have embraced it as the ontology which their predecessors had failed to make unnecessary. Scientific realism is metaphysics, shameless or unashamed.

Abstract: Chomsky (1986) has claimed that the prima facie incompatibility between descriptive linguistics and semantic externalism proves that an externalist semantics is impossible. Although it is true that a strong form of externalism does not cohere with descriptive linguistics, sociolinguistic theory can unify the two approaches. The resulting two-level theory reconciles descriptivism, mentalism, and externalism by construing community languages as a function of social identification. This approach allows a fresh look at names and definite descriptions while also responding to Chomsky's (...) (1993, 1995) challenge to articulate an externalist theory of meaning that can be used in the scientific investigation of language. (shrink)

Michael Dummett’s realism debate is a semantic dispute about the kind of truth conditions had by a given class of sentences. According to his semantic realist, the truth conditions are potentially verification-transcendent in that they may obtain (or not) despite the fact that we may be forever unable to recognize whether they obtain. According to Dummett’s semantic anti-realist, the truth conditions are of a different sort. Essentially, for the anti-realist, that the truth conditions obtain (whenever they do) is a matter (...) that is always recognizable by us in principle. On this view, truth cannot outrun all possible human knowledge. Unsurprisingly, the outcome of the debate is sometimes said to hinge on whether all truths are knowable.1 More carefully the point of contention is the following.. (shrink)

This paper presents an argument for metaphysical realism, understood as the claim that the world has structure that would exist even if our cognitive activities never did. The argument is based on the existence of a structured world at a time when it was still possible that we would never evolve. But the interpretation of its premises introduces subtleties: whether, for example, these premises are to be understood as assertions about the world or about our evidence, internally or externally, via (...) assertibility conditions or truth conditions – and what sorts of beings are included in the `we' upon whose cognitions the antirealist supposes the structure of the world to depend. I argue that antirealism can provide no defensible, fully articulated interpretation of the premises that either shows them not to be true or defeats the reasoning. (shrink)

All through the literatura, the question about what is a logical constant has recieved many answers, from model-theoretic aproaches,, to answers that focus in the inferential practice as meaning,,. Detractors of the second tradition presented many ineludible incovenients, in particular, the logical constant named ‘tonk’. Inferentialist tryed many solutions, in particular they presented the concept of ‘harmony’. The goal of this paper is to show that the different criteria of ‘harmony’ used in the proof-theoretic semantics to determine what is and (...) what is not a logical constant fail to be necessary or sufficient. I will show the philosophical reasons that make this concept appear and then i will describe the different ways in wich the literatura understads the concept of ‘harmony’. Then I will show that they subgenerate or overgenerate connectives with some counterexamples. Finaly, I will explain some philosophical reasons that should delimitate where to go towards a satisfactory definition of ‘harmony’. (shrink)

Dummett’s notion of indefinite extensibility is influential but obscure. The notion figures centrally in an alternative Dummettian argument for intuitionistic logic and anti-realism, distinct from his more famous, meaning-theoretic arguments to the same effect. Drawing on ideas from Dummett, a precise analysis of indefinite extensibility is proposed. This analysis is used to reconstruct the poorly understood alternative argument. The plausibility of the resulting argument is assessed.

Frederic Stoutland (1982a, 1982b) has argued that a Davidsonian theory of meaning is incompatible with a realist view of truth, on which the truth-conditions of sentences consist of mind-independent states of affairs or concatenations of extra-linguistic objects. In this paper we show that Stoutland’s argument is a failure.

This dissertation is centered around a set of apparently conflicting intuitions that we may have about mathematics. On the one hand, we are inclined to believe that the theorems of mathematics are true. Since many of these theorems are existence assertions, it seems that if we accept them as true, we also commit ourselves to the existence of mathematical objects. On the other hand, mathematical objects are usually thought of as abstract objects that are non-spatiotemporal and causally inert. This makes (...) it difficult to understand how we can have knowledge of them and how they can have any relevance for our mathematical theories. I begin by characterizing a realist position in the philosophy of mathematics and discussing two of the most influential arguments for that kind of view. Next, after highlighting some of the difficulties that realism faces, I look at a few alternative approaches that attempt to account for our mathematical practice without making the assumption that there exist abstract mathematical entities. More specifically, I examine the fictionalist views developed by Hartry Field, Mark Balaguer, and Stephen Yablo, respectively. A common feature of these views is that they accept that mathematics interpreted at face value is committed to the existence of abstract objects. In order to avoid this commitment, they claim that mathematics, when taken at face value, is false. I argue that the fictionalist idea of mathematics as consisting of falsehoods is counter-intuitive and that we should aim for an account that can accommodate both the intuition that mathematics is true and the intuition that the causal inertness of abstract mathematical objects makes them irrelevant to mathematical practice and mathematical knowledge. The solution that I propose is based on Rudolf Carnap's distinction between an internal and an external perspective on existence. I argue that the most reasonable interpretation of the notions of mathematical truth and existence is that they are internal to mathematics and, hence, that mathematical truth cannot be used to draw the conclusion that mathematical objects exist in an external/ontological sense. (shrink)

Freud justified his extensive theorizing about dreams by the observation that they were “the royal road” to something much more general: namely, our unconscious mental life. The current preoccupation with the theory of excuse in criminal law scholarship (including my own) can be given a similar justification, for the excuses are the royal road to theories of responsibility generally. The thought is that if we understand why we excuse in certain situations but not others, we will have also gained a (...) much more general insight into the nature of responsibility itself. Nowhere has this thought been more evident than in the century-old focus of criminal law theoreticians on the excuse of insanity, a focus that could not be justified by the importance of the excuse itself.In this paper I wish to isolate two theories of excuse, each of which instantiates its own distinctive theory of responsibility. One is what I shall call the choice theory of excuse, according to which one is excused for the doing of a wrongful action because and only because at the moment of such action's performance, one did not have sufficient capacity or opportunity to make the choice to do otherwise. Such a choice theory of excuse instantiates a more general theory of responsibility, according to which we are responsible for wrongs we freely choose to do, and not responsible for wrongs we lacked the freedom (capacity and opportunity) to avoid doing. The second I shall call the character theory of excuse, according to which one is excused for the doing of a wrongful action because and only because such action is not determined by (or in some other way expressive of) those enduring attributes of ourselves we call our characters. (shrink)