This paper offers a new interpretation for Wittgenstein`s treatment of mathematical identities. As it is widely known, Wittgenstein`s mature philosophy of mathematics includes a general rejection of abstract objects. On the other hand, the traditional interpretation of mathematical identities involves precisely the idea of a single abstract object – usually a number –named by both sides of an equation.

Modality presents notorious philosophical problems, including the epistemic problem of how we could come to know modal facts and metaphysical problems about how to place modal facts in the natural world. These problems arise from thinking of modal claims as attempts to describe modal features of this world that explain what makes them true. Here I propose a different view of modal discourse in which talk about what is “metaphysically necessary” does not aim to describe modal features of the world, (...) but, rather, provides a particularly useful way of expressing constitutive semantic and conceptual rules in the object language. The result is a “modal normativist” view that enables us to avoid the epistemic problems of modality and mitigate the metaphysical worries, while also leaving open the possibility of a unified account of the function of modal language. Finally, I address a serious challenge: we have the norms we do in order to track the modal facts of the world, so that the order of explanation must go in the opposite direction. I close by showing how the normativist may answer that challenge. (shrink)

In this chapter a new problem about rule-following is outlined, one that is distinct both from Kripke’s and Wright’s versions of the problem. This new problem cannot be correctly responsed to, as Kripke’s can, by invoking Wright’s Intentional Account of rule-following. The upshot might be called, following Kant, an antinomy of pure reason: we both must — and cannot — make sense of someone’s following a rule. The chapter explores various ways out of this antinomy without here endorsing any of (...) them. (shrink)

In classical logic, a contradiction allows one to derive every other sentence of the underlying language; paraconsistent logics came relatively recently to subvert this explosive principle, by allowing for the subsistence of contradictory yet non-trivial theories. Therefore our surprise to find Wittgenstein, already at the 1930s, in comments and lectures delivered on the foundations of mathematics, as well as in other writings, counseling a certain tolerance on what concerns the presence of contradictions in a mathematical system. ‘Contradiction. Why just this (...) spectre? This is really very suspicious.’ ( Philosophical Remarks III–56) In the last decades, several authors (e.g. Arrington, Hintikka, Van Heijenoort, Wright, Wrigley) have been digging into Wittgenstein’s rather non-standard standpoint on what concerns the interpretation and import of contradiction in logic and mathematics, and many other authors (e.g. da Costa, Goldstein, Granger, Marconi) have been investigating the possibility of taking Wittgenstein seriously as one of the early forerunners of paraconsistency. While many advances have been made on the first front, the second set of investigations has led almost exclusively to negative results: no, no operational proposal about the construction of a logic in which (some) contradictions are made inoffensive can be read from Wittgenstein’s philosophical work; in fact, it appears that the most one can find there is the exhortation for mathematicians to alter their attitude with respect to contradictions and to consistency proofs. The play is done, and one looks for a resume of the opera. This paper fills that blank, as a thorough investigation of the possible relations between Wittgenstein and paraconsistency. DOI:10.5007/1808-1711.2010v14n1p135. (shrink)

In 1982 Saul A. Kripke proposed a reconstruction of the central insights of Ludwig Wittgenstein's remarks on rule-following. The reconstruction prominently featured a sceptical challenge which soon was recognised as a new and very radical form of scepticism. According to the challenge there is no fact of the matter which constitutes meaning. As there is no such fact, the first-person authority people intuitively seem to have concerning what they mean is also baseless. In response to the sceptic, many solutions have (...) been proposed. This thesis is about one family of solutions, according to which facts about meaning are sui generis and can neither be reduced to other facts about the world nor to non-semantic facts about the human mind. The non-reductionist proposals by Colin McGinn and Crispin Wright will be assessed in detail and arguments against both will be introduced. The arguments stem only partially from Kripke himself, some are based on recent literature, others are completely new. The emerging situation will be used as a basis to propose an alternative non-reductionism about meaning-facts. (shrink)

Modality and Anti-Metaphysics critically examines the most prominent approaches to modality among analytic philosophers in the twentieth century, including essentialism. Defending both the project of metaphysics and the essentialist position that metaphysical modality is conceptually and ontologically primitive, Stephen McLeod argues that the logical positivists did not succeed in banishing metaphysical modality from their own theoretical apparatus and he offers an original defence of metaphysics against their advocacy of its elimination. -/- Seeking to assuage the sceptical worries which underlie modal (...) anti-realism, McLeod provides an original contribution to essentialist epistemology, engaging with current debates about modality and suggesting that standard essentialist approaches to some issues in the philosophies of logic and language require revision. -/- This book offers valuable insights to professional philosophers, postgraduates and advanced undergraduates interested in metaphysics, philosophy of logic or the history of twentieth-century analytic philosophy. (shrink)

The later Wittgenstein’s perspective on mathematical sentences as norms is motivated for sentences belonging to Hilbertian axiomatic systems where the axioms are treated as implicit definitions. It is shown that in this approach the axioms are employed as norms in that they function as standards of what counts as using the concepts involved. This normative dimension of their mode of use, it is argued, is inherited by the theorems derived from them. Having been motivated along these lines, Wittgenstein’s perspective on (...) mathematical language may appeal also to those who are not friends of or experts on Wittgenstein’s later philosophy of mathematics. (shrink)

McFetridge (in Logical necessity and other essays . London: Blackwell, 1990 ) suggests that to treat a proposition as logically necessary—to believe a proposition logically necessary, and to manifest that belief—is a matter of preparedness to deploy that proposition as a premise in reasoning from any supposition. We consider whether a suggestion in that spirit can be generalized to cover all cases of absolute necessity, both logical and non-logical, and we conclude that it can. In Sect. 2, we explain the (...) significance that such an account of manifestation of belief in absolute necessity has for the prospects of a non-realist theory of modality. In Sect. 3, we offer a sympathetic articulation of the detail that underlies the McFetridge conception of belief in logical necessity. In Sects. 4 and 5, we show that the conception so articulated will not generalize to encompass all cases of belief in absolute necessity and proceed to offer a remedy. Our proposal is based upon a distinction between two kinds of suppositional act: A-supposing and C-supposing (Sect. 6). In Sect. 7, we then explain and defend our central thesis: (roughly) that (manifestation of) belief in absolute necessity is a matter of preparedness to deploy as a premise in reasoning under any C-supposition. Finally, we indicate that there is some promise in the parallel thesis that manifestation of the treatment of a proposition as a priori is a matter of preparedness to deploy as a premise in reasoning under any A-supposition (Sect. 8). (shrink)

The relation between Wittgenstein's philosophy of mathematics and mathematical Intuitionism has raised a considerable debate. My attempt is to analyse if there is a commitment in Wittgenstein to themes characteristic of the intuitionist movement in Mathematics and if that commitment is one important strain that runs through his Remarks on the foundations of mathematics. The intuitionistic themes to analyse in his philosophy of mathematics are: firstly, his attacks on the unrestricted use of the Law of Excluded Middle; secondly, his distrust (...) of non-constructive proofs; and thirdly, his impatience with the idea that mathematics stands in need of a foundation. These elements are Fogelin's starting point for the systematic reconstruction of Wittgenstein's conception of mathematics. (shrink)

Dummett's case against platonism rests on arguments concerning the acquisition and manifestation of knowledge of meaning. Dummett's arguments are here criticized from a viewpoint less Davidsonian than Chomskian. Dummett's case against formalism is obscure because in its prescriptive considerations are not clearly separated from descriptive. Dummett's implicit value judgments are here made explicit and questioned. ?Combat Revisionism!? Chairman Mao.

The two main challenges of the theory of conceptual content presented by Robert Brandom in Making It Explicit are to account for a referential dimension of conceptual content and to account for the objectivity of conceptual norms. Brandom tries to meet both these challenges in chapter 8 of his book. I argue that the accounts presented there can only be understood if seen against the background of Brandom's theory of communication developed in chapter 7. This theory is motivated by the (...) well-known problem that semantic holism threatens the possibility of communication because it has the consequence that words mean different things in different mouths. Brandom offers a solution to this problem in terms of what he calls recurrence commitments. I show that chapter 8 of Making It Explicit should be understood as arguing that a practice that includes acknowledging interpersonal recurrence commitments institutes both conceptual contents with a referential dimension and objective conceptual norms. I close by raising the objection that Brandom's argument can only show that conceptual norms are communally shared and not that they are objective. I propose an emendation of this argument, having recourse to a practice Brandom refers to as rational rectification in his new book Between Saying and Doing. (shrink)

This paper argues that most of the alleged straight solutions to the sceptical paradox which Kripke ascribed to Wittgenstein can be regarded as the first horn of a dilemma whose second horn is the paradox itself. The dilemma is proved to be a by‐product of a foundationalist assumption on the notion of justification, as applied to linguistic behaviour. It is maintained that the assumption is unnecessary and that the dilemma is therefore spurious. To this end, an alternative conception of the (...) justification of linguistic behaviour is outlined, a conception that vindicates some of the insights behind Kripke's Wittgenstein's sceptical solution of the paradox. This alternative conception is defended against two objections (both familiar from McDowell's works): (1) that it would imply that for the linguistic community there is no authority, no standard to meet and, therefore, no possibility of error and (2) that it would lead to a kind of idealism. (shrink)

To explain an intentional action one must exhibit the agent’s reasons. Donald Davidson famously argued that the only clear way to understand action explanation is to hold that reasons are causes. Davidson’s discussion conflated two issues: whether reasons are causes and whether reasons causally explain intentional action. Contemporary work on explanation and normativity help disentangle these issues and ground an argument that intentional action explanations cannot be a species of causal explanation. Interestingly, this conclusion is consistent with Davidson’s conclusion that (...) reasons are causes. In other words, reasons are causes, but rationalizing explanations are not causal explanations. Key Words: action theory • explanation • causal explanation • rationality • Donald Davidson. (shrink)

The paper defends causal explanationism concerning our modal intuitions and judgments, and, in particular, the following claims. If a causally explainable mirroring or “pre-established harmony” between our mind and modal reality obtains, we are justified in believing it does. We do not hold our modal beliefs compulsively and blindly but with full subjective and objective justification. Therefore, causal explanation of our modal beliefs does not undermine rational trust in them. Explanation and trust support each other. In contrast, anti-explanationists, claim that (...) causal explanation of intuitions and judgments undermines rational trust in them. They especially target causal explanation in terms of pre-established harmony between our mind, shaped by causal processes, and the underlying modal structure of reality. The paper argues against them. The argument builds upon the claim that the appeal to modal facts is indispensable for systematization and explanation of non-modal ones. Therefore, we should assume that modal facts exist and are not disjoint and isolated from actual facts. The modal structure of the universe intervenes in the non-modal reality. Causal processes indirectly carry information about deep modal structure. Any causal explanation of our intuitional modal beliefs should start from this indirect contact with and information about modal facts. Therefore, if our intuitional modal beliefs are true and causally explainable, they are true in virtue of the deep underlying modal structure. They are sensitive to modal reality and track it. We can come to know this fact, and thus strengthen our spontaneous trust in our modal intuitions. (shrink)

Alberto Coffa used the phrase "the Copernican turn in semantics" to denote a revolutionary transformation of philosophical views about the connection between the meanings of words and the acceptability of sentences and arguments containing those words. According to the new conception resulting from the Copernican turn, here called "the Copernican view", rules of use are constitutive of the meanings of words. This view has been linked with two doctrines: (A) the instances of meaning-constitutive rules are analytically and a priori true (...) or valid; (B) to grasp a meaning is to accept its rules. The pros and cons of different versions of the Copernican view, ascribable to Wittgenstein, Carnap, Gentzen, Dummett, Prawitz, Boghossian and other authors, will be weighed. A new version will be proposed, which implies neither (A) nor (B). (shrink)

Normativism in the theory of meaning and content is the view that linguistic meaning and/or intentional content are essentially normative. As both normativity and its essentiality to meaning/content can be interpreted in a number of different ways, there is now a whole family of views laying claim to the slogan “meaning/content is normative”. In this essay, we discuss a number of central normativist theses, and we begin by identifying different versions of meaning normativism, presenting the arguments that have been put (...) forth for and against them. (shrink)

Ideas on meaning, rules and mathematical proofs abound in Wittgenstein’s writings. The undeniable fact that they are present together, sometimes intertwined in the same passage of Philosophical Investigations or Remarks on the Foundations of Mathematics, does not show, however, that the connection between these ideas is necessary or inextricable. The possibility remains, and ought to be checked, that they can be plausibly and consistently separated. I am going to examine two views detectable in Wittgenstein’s works: one about proofs, the other (...) about meaning and rules. The first is the denial of the objectivity of proof. The second is a conception of meaning stemming from the rule-following considerations. I shall argue that, though Wittgenstein seems to conjoin the two views, they can be, and should be, separated1. (shrink)

Many now accept the thesis that norms are somehow constitutively involved in people's contentful intentional states. I distinguish three versions of this normative thesis that disagree about the type of norms constitutively involved. Are they objective norms of correctness, subjective norms of rationality, or intersubjective norms of social practices? I show the advantages of the third version, arguing that it improves upon the other two versions, as well as incorporating their principal insights. I then defend it against two serious challenges: (...) (1) If content is constituted by others' normative judgments, how can content be causally efficacious? (2) This account appears to make having contentful thoughts a matter of people having contentful thoughts about your thoughts. That appears to be viciously circular and so can't be naturalistic. (shrink)

forthcoming in R. Cameron, B. Hale and A. Hoffmann (ed.s), The Logic, Epistemology and Metaphysics of Modality, Oxford University Press. Presents a concept-grounding account of modal knowledge.

The paper puts forward the thesis of conceptual pragmatism: that there are pragmatic choices to be made between distinct but similar concepts within various contexts. It is argued that this thesis should be acceptable to all who believe in concepts, whether the believers are platonists, realists or anti-realists. It is argued that the truth of the thesis may help to resolve many long-standing debates, and that in any case it will lead to an extension of philosophical method. The paper then (...) briefly considers the concepts of belief and desire as a case-study, and argues for the recognition of the practical reasoner's stance (to stand alongside Dennett's intentional stance), relative to which we should select concepts of belief and desire which are broadly cartesian. (shrink)

The German physicist Heinrich Hertz played a decisive role for Wittgenstein's use of a unique philosophical method. Wittgenstein applied this method successfully to critical problems in logic and mathematics throughout his life. Logical paradoxes and foundational problems including those of mathematics were seen as pseudo-problems requiring clarity instead of solution. In effect, Wittgenstein's controversial response to David Hilbert and Kurt Gödel was deeply influenced by Hertz and can only be fully understood when seen in this context. To comprehend the arguments (...) against the metamathematical programme, and to appreciate how profoundly the philosophical method employed actually shaped the content of Wittgenstein's philosophy, it is necessary to make an intellectual biographical reconstruction of their philosophical framework, tracing the Hertzian elements in the early as well as in the later writings. In order to write Wittgenstein's biography, we have to take seriously the coherence of his thought throughout his life, and not let convenient philosophical ideologies be our guidance in drawing up a “Wittgensteinian philosophy”. To do so, we have to take a second look upon what he actually wrote, not only in the already published material, but in the entire Nachlass. Clearly, this is not easily done, but it is a necessary task in the historical reconstruction of Wittgenstein's life and work. (shrink)

This is a short, and therefore necessarily very incomplete discussion of one of the great questions of modern philosophy. I return to a station at which an interpretative train of thought of mine came to a halt in a paper written almost 20 years ago, about Wittgenstein and Chomsky,[1] hoping to advance a little bit further down the track. The rule-following passages in the Investigations and Remarks on the Foundations of Mathematics in fact raise a number of distinct issues about (...) rules, meaning, objectivity, and reasons, whose conflation is encouraged by the standard caption, "the Rule-following Considerations".[2] So, let me begin by explaining my focus here. (shrink)

Many people claim that semantic content is normative, and that therefore naturalistic theories of content face a potentially insuperable difficulty. The normativity of content allegedly undermines naturalism by introducing a gap between semantic 'ought's and the explanatory resources of naturalism. I argue here that this problem is not ultimately pressing for naturalists. The normativity thesis, I maintain, is ambiguous; it could mean either that the content of a term prescribes a pattern of use, or that it merely determines which pattern (...) of use can be described as 'correct'. For the antinaturalist argument to go forward, content must be prescriptive. I argue, however, that it is not. Moreover, the thesis that content supplies standards for correct use is insufficient to supply a similar, a priori objection to naturalism. (shrink)

The aim of this paper is to discover whether or not a solitary individual, a human being isolated from birth, could become a rule-follower. The argumentation against this possibility rests on the claim that such an isolate could not become aware of a normative standard, with which her actions could agree or disagree. As a consequence, theorists impressed by this argumentation adopt a view on which the normativity of rules arises from corrective practices in which agents engage in a community. (...) However, it has been suggested that an isolated individual could engage in such a practice by herself. Three prospective examples of such cases are considered, and the possibility of solitary rule-following is vindicated. Furthermore, the nature of the goals at which rule-following practices generally aim is clarified. (shrink)

This paper presents a new argument to defend the normativity of meaning, specifically the thesis that there are no meanings without norms. The argument starts from the observation inferentialists have emphasized that incompatibility relations between sentences are a necessary part of meaning as it is understood. We motivate this approach by showing that the standard normativist strategy in the literature, which is developed in terms of veridical reference that may swing free from the speaker’s understanding, violates the ought-implies-can principle, but (...) ours does not. In addition, our approach is superior because, unlike the representationalist approach, it can be extended from declarative sentences to non-representational uses of language. In this paper, however, we only formulate the argument for the base case that involves incompatibility relations between declarative sentences. The goal is not to derive norms from something that is not normative, but to explicate the distinctive type of normativity that is built into meaning as it is understood by language-users. The explication proceeds in two steps. (1) For any sentence s a speaker understands, there is an incompatible sentence s’ the speaker understands to be incompatible with s. (2) In virtue of understanding this incompatibility of meanings, she ought not to be committed to both s and s’. This prohibition is not derived from instrumental practical reason, nor is it based on representational correctness, but its source is the incompatibility of meanings. (shrink)

Ludwig Wittgenstein in his later works often implies commitment to a doctrine of the autonomy or arbitrariness of grammar. This chapter discusses the conception of grammar that is presupposed in this doctrine and then explains the doctrine itself. The chapter also explains a sense in which grammar is not autonomous or arbitrary for Wittgenstein and discusses some possible criticisms of the doctrine. It should be noted at the outset that this whole area of exegetical concern is one in which the (...) fairly widespread conception in the secondary literature that the later Wittgenstein is a complete “quietist” in philosophy ‐ i.e., someone who advances no positive doctrines of his own, although encouraged by some of his own statements, seems impossible to sustain. Wittgenstein's doctrine of the autonomy or arbitrariness of grammar presupposes a highly distinctive conception of grammar, one which at least prima facie has little to do with our everyday conception of grammar. (shrink)

Brandom (Citation1994) made inferentialism an intensely debated idea in the philosophy of language in the last three decades. Inferentialism is a view that associates the meaning of linguistic expression with the role said expression plays in inferences. It seems rather uncontroversial that the correct theory of meaning should distinguish between linguistic correctness and factual correctness. For instance, speaker S can be wrong in saying ‘I have arthritis’ in two distinct ways: (i) S fails to apply a word correctly to make (...) a true statement due to having made a factual error, and (ii) S uses an expression incorrectly because they are wrong about its meaning. In this paper, I show that properly understood normative inferentialism can make room for such a distinction. I propose that linguistic correctness is a structural issue: linguistic mistakes stem from the improper or insufficient acquisition of an inferential role. Factual correctness, on the other hand, is a one-off issue of the correct application of inferential rules to a particular situation. I argue that, by tying the issue of correctness to the game of giving and asking for reasons, inferentialism can establish a reliable method for distinguishing between two types of correctness (and mistakes). (shrink)

The main question of metasemantics, or foundational semantics, is why an expression token has the meaning (semantic value) that it in fact has. In his reading of Ludwig Wittgenstein’s later work, Saul Kripke presented a skeptical challenge that threatened to make the foundational question unanswerable. My first contention in this paper is that the skeptical challenge indeed poses an insoluble paradox, but only for a certain kind of metasemantic theory, against which the challenge effectively works as a reductio ad absurdum (...) argument. My second contention is that as a result of rejecting the theory which entails a paradoxical outcome, we will see that the foundational question essentially involves a temporal dimension. After arguing that the skeptical challenge gives us a strong reason to adopt a historical view of meaning, I shall further argue against certain authors who claim that meanings not only have histories but futures as well, or that the meaning of a word may change retroactively in time as a consequence of counterfactual change in its future use. The major aim of the paper is thus to bring together the arguably interrelated debates about the skeptical challenge and temporal externalism in philosophy of language. (shrink)

This paper addresses a problem about aesthetic normativity raised by Kant. Can aesthetic experiences be appropriate or inappropriate to their objects? And, if so, how is that possible given that, according to Kant, aesthetic experience is not objective? Kant thought the answer to the first question was yes. But his official answer to the second question, in terms of the free play of the faculties, is obscure. The paper offers a clearer answer, inspired by Kant, which invokes Wittgenstein’s notion of (...) “knowing how to go on.” Aesthetic normativity is problematic only on the assumption that claims to the normativity of one’s responses to things must be based on the recognition of objective properties of those things. However, Wittgenstein’s discussion shows that we need not accept that assumption. There can be legitimate claims to the normativity of one’s responses which do not rely on those responses’ reflecting appreciation of objective facts. (shrink)

Since the publication of the Remarks on the Foundations of Mathematics, Wittgenstein’s interpreters have endeavored to reconcile his general constructivist/anti-realist attitude towards mathematics with his confessed anti-revisionary philosophy. In this article, the author revisits the issue and presents a solution. The basic idea consists in exploring the fact that the so-called “non-constructive results” could be interpreted so that they do not appear non-constructive at all. The author substantiates this solution by showing how the translation of mathematical results, given by the (...) possibility of translation between logics, can be seen as a tool for partially implementing the solution Wittgenstein had in mind. (shrink)

What is the source of logical and mathematical truth? This book revitalizes conventionalism as an answer to this question. Conventionalism takes logical and mathematical truth to have their source in linguistic conventions. This was an extremely popular view in the early 20th century, but it was never worked out in detail and is now almost universally rejected in mainstream philosophical circles. Shadows of Syntax is the first book-length treatment and defense of a combined conventionalist theory of logic and mathematics. It (...) argues that our conventions, in the form of syntactic rules of language use, are perfectly suited to explain the truth, necessity, and a priority of logical and mathematical claims, as well as our logical and mathematical knowledge. (shrink)

This project is an investigation into the prospects for an antirealist theory of essence. Essentialism is the claim that at least some things have some of their properties essentially. Essentialist discourse includes claims such as “Socrates is essentially human”, and “Socrates is accidentally bearded”. Historically, there are two ways of interpreting essentialist discourse. I call these positions ‘modal essentialism’ and ‘neo-Aristotelian essentialism’. According to modal essentialism, for Socrates to be essentially human is for it to be necessary that he be (...) a human if he exists, and for Socrates to accidentally have a beard is for it to be contingent that Socrates has a beard if he exists. According to neo-Aristotelian essentialism, objects have definitions in something like the way words do. For Socrates to be essentially human but accidentally bearded is for it to be part of the definition of Socrates that he is human, but not part of that definition that he is bearded. I argue that both are susceptible to antirealist interpretation. This thesis sets about showing that this is the case. In Chapters One and Two I investigate neo-conventionalist theories of modality, in the hope of using such a position to develop an antirealist modal essentialism. In Chapter Three I discuss the debate between modal and neo-Aristotelian essentialism and conclude that it is by no means settled. In Chapter Four I develop an antirealist neo-Aristotelian essentialism based on the mechanism of one of the neo-conventionalist accounts of modality. In Chapter Five I argue that this account is in a better position to give an essentialist theory of necessity than its realist counterparts. I conclude that, regardless of whether one is a modal or neo-Aristotelian essentialist, antirealist essentialism is a viable theory of essence that is worthy of consideration in contemporary debate. (shrink)

In a famous passage from the Philosophical Investigations, Wittgenstein describes a pupil who has been learning to write out various sequences of numbers in response to orders such as “+1” and “+2”. He has shown himself competent for numbers up to 1000, but when we have him continue the “+2” sequence beyond 1000, he writes the numerals 1004, 1008, 1012. As Wittgenstein describes the case: We say to him, “Look what you’re doing!” — He doesn’t understand us. We say “You (...) should have added two; look how you began the series!” — He answers: “Yes! Isn’t it right? I thought that’s how I should [sollen] do it. — Or suppose he were to say, pointing to the series, “But I went on in the same way!”1The passage continues:— It would now be no use to us to say “But don’t you see…?” — and repeat for him the old explanations and examples. — In such a case, we might perhaps say: this person naturally understands our order, once given our explanations, as we would understand the order “Add 2 up to 1000, 4 up to 2000, 6 up to 3000, and so on.”. (shrink)

ABSTRACT In ‘The philosophical basis of intuitionistic logic’, Michael Dummett discusses two routes towards accepting intuitionistic rather than classical logic in number theory, one meaning-theoretical and the other ontological. He concludes that the former route is open, but the latter is closed. I reconstruct Dummett's argument against the ontological route and argue that it fails. Call a procedure ‘investigative’ if that in virtue of which a true proposition stating its outcome is true exists prior to the execution of that procedure; (...) and ‘generative’ if the existence of that in virtue of which a true proposition stating its outcome is true is brought about by the execution of that procedure. The problem with Dummett's argument then is that a particular step in it, while correct for investigative procedures, is not correct for generative ones. But it is the latter that the ontological route is concerned with. (shrink)

This article examines Hilary Putnam's work in the philosophy of mathematics and - more specifically - his arguments against mathematical realism or objectivism. These include a wide range of considerations, from Gödel's incompleteness-theorem and the limits of axiomatic set-theory as formalised in the Löwenheim-Skolem proof to Wittgenstein's sceptical thoughts about rule-following, Michael Dummett's anti-realist philosophy of mathematics, and certain problems – as Putnam sees them – with the conceptual foundations of Peano arithmetic. He also adopts a thought-experimental approach – a (...) variant of Descartes' dream scenario – in order to establish the in-principle possibility that we might be deceived by the apparent self-evidence of basic arithmetical truths or that it might be ‘rational’ to doubt them under some conceivable set of circumstances. Thus Putnam assumes that mathematical realism involves a self-contradictory ‘Platonist’ idea of our somehow having quasi-perceptual epistemic ‘contact’ with truths that in their very nature transcend the utmost reach of human cognitive grasp. On this account, quite simply, ‘nothing works’ in philosophy of mathematics since wecan either cling to that unworkable notion of objective truth or abandon mathematical realism in favour of a verificationist approach that restricts the range of admissible statements to those for which we happen to possess some means of proof or ascertainment. My essay puts the case, conversely, that these hyperbolic doubts are not forced upon us but result from a false understanding of mathematical realism – a curious mixture of idealist and empiricist themes – which effectively skews the debate toward a preordained sceptical conclusion. I then go on to mount a defence of mathematical realism with reference to recent work in this field and also to indicate some problems – as I seethem – with Putnam's thought-experimental approach as well ashis use of anti-realist arguments from Dummett, Kripke, Wittgenstein, and others. (shrink)

The Four-Colour Theorem (4CT) proof, presented to the mathematical community in a pair of papers by Appel and Haken in the late 1970's, provoked a series of philosophical debates. Many conceptual points of these disputes still require some elucidation. After a brief presentation of the main ideas of Appel and Haken’s procedure for the proof and a reconstruction of Thomas Tymoczko’s argument for the novelty of 4CT’s proof, we shall formulate some questions regarding the connections between the points raised by (...) Tymoczko and some Wittgensteinian topics in the philosophy of mathematics such as the importance of the surveyability as a criterion for distinguishing mathematical proofs from empirical experiments. Our aim is to show that the “characteristic Wittgensteinian invention” (Mühlhölzer 2006) – the strong distinction between proofs and experiments – can shed some light in the conceptual confusions surrounding the Four-Colour Theorem. (shrink)

The paper discusses an objection, put forward by - among others - John McDowell, to Kripke’s Wittgenstein’s non-factualist and relativist view of semantic discourse. The objection goes roughly as follows: while it is usually possible to be a relativist about a given domain of discourse without being a relativist about anything else, relativism about semantic discourse entails global relativism, which in turn entails subjective idealism, which we can reasonably assume to be false. The paper’s first section sketches Kripke’s Wittgenstein’s ideas (...) about semantic discourse and gives a fully explicit formulation of the objection. The second section describes and briefly discusses the formal apparatus needed to evaluate the objection - which is basically equivalent to John MacFarlane’s recent development of David Kaplan’s classic semantic framework. Finally, the third section explains in detail why the objection fails. I show that even though relativism about semantic discourse does entail a form of global relativism, the relativism in question does not entail anything like Berkeleyan or Fichtean idealism. This particular kind of relativism holds that which character (in Kaplan’s sense) is associated to a given utterance depends on what MacFarlane calls “the context of assessment”. (shrink)

The dissertation attempts to answer the question of how to theorize resistance from within the philosophy of social science. To answer this question we must consider more than just the philosophy of social science; we also must look to political and moral philosophy. Resistance to the social norms of one’s community is possible to theorize from within the philosophy of social science once we develop a sufficiently nuanced account of social and moral communities, according to which membership in a community (...) is not defined by sharing judgments, conceptual frameworks, or comprehensive worldviews, but by sharing terms of discourse so that discussion about judgments, conceptual frameworks, and comprehensive worldviews is possible. Understanding the structure of one’s moral community is not the same as to endorsing that structure. This suggests that contestation is already present within communities about what ‘we’ do, up to and including who ‘we’—as a ‘community’—are. Challenging communitarian understandings of what makes a community a community, I argue that communities are best understood as forming around common concerns or perceptions of problems. This contestation plays a major role in determining the identities of communities, and these identities are constantly shifting. (shrink)

Is there a plausible middle position in the debate between realists and constructivists about categories or kinds? Such a position may seem to be contained in the account of triangulation that Donald Davidson develops in recent writings. On this account, the kinds we pick out are determined by an interaction between our shared similarity responses and causal relations between us and things in our environment. So kinds and categories are neither imposed on us by the nature of the world, nor (...) imposed by us on an intrinsically unstructured reality. But the picture derivable from Davidson's account of triangulation can be interpreted in either of two ways. On one interpretation, it collapses into constructivism. On the other, it turns out to be very close to the most plausible versions of realism. It is argued that Davidson's attempts to distinguish his view from Putnam's realism about natural kinds are unsuccessful. So Davidson's account of triangulation does indeed suggest a plausible view of kinds. But that view is a version of traditional realist views, not an alternative to them. (shrink)

In the scholarship on Wittgenstein’s later philosophy of mathematics, the dominant interpretation is a theoretical one that ascribes to Wittgenstein some type of ‘ism’ such as radical verificationism or anti-realism. Essentially, he is supposed to provide a positive account of our mathematical practice based on some basic assertions. However, I claim that he should not be read in terms of any ‘ism’ but instead should be read as examining philosophical pictures in the sense of unclear conceptions. The contrast here is (...) that basic assertions that frame philosophical ‘isms’ are propositional such that they are subject to normal argumentative evaluation, while pictures in Wittgenstein’s sense are non-propositional—they lack a clear truth condition. They, therefore, need clarification rather than argumentation. In this paper, I provide a detailed analysis of Wittgenstein’s treatment of philosophical pictures with special focus on his argument on contradiction. I begin by explaining the problem with this trend of theoretical interpretation, taking Steve Gerrard’s otherwise excellent interpretation as a representative example and pointing out why it is problematic. Next, I will argue that those problems do not arise if we take Wittgenstein’s task as the clarification of philosophical pictures. I do this, first, by explaining Wittgenstein’s method using his argument concerning the Augustinian Picture in Philosophical Investigations and then pointing out that the same method can be identified in the crucial arguments in his philosophy of mathematics. Finally, in order to connect my interpretation with the current scholarship, I will explain the relation of my interpretation with those of New Wittgensteinian scholars. (shrink)

In “Correspondence to Reality in Ethics”, Mario Brandhorst examines the view of ethics that Wittgenstein took in his later years. According to Brandhorst, Wittgenstein leaves room for truth and falsity, facts, correspondence and reality in ethics. Wittgenstein's target, argues Brandhorst, is objectivity. I argue that Brandhorst's arguments in favour of truth, facts, reality and correspondence in ethics invite similar arguments in favour of objectivity, that Brandhorst does not recognise this because his conception of objectivity is distorted by a Platonist picture (...) and that he misinterprets the passage which he takes to support a Wittgensteinian case against objectivity. (shrink)

Traditional conventionalism about modality claims that a proposition is necessarily true iff it is true by convention. In the wake of the widespread repudiation of truth-byconvention, traditional conventionalism has fallen out of favour. However, a family of theories of modality have arisen that, whilst abandoning truth-by-convention, retain the spirit of traditional conventionalism. These ‘neo-conventionalist’ theories surpass their forebears and don’t fall victim to the criticisms inherited through truth-by-convention. However, not all criticisms levelled at traditional conventionalism target truth-by-convention. Any conventional theory (...) of modality must face the contingency problem. This claims that the contingency of our linguistic conventions jeopardises the necessity of the necessities they determine. I present the contingency problem as relevant to both the traditional conventionalist and the neo-conventionalist. I examine a response from Einheuser that builds upon a response from Wright. I show that the Einheuser response does more to accommodate the conventionalist’s modal beliefs, but that it does not fully satisfy some further conditions that ought to be laid upon such a response. I then suggest how the response can be revised so as to satisfy these conditions. The resulting model of conventionalism is compatible with the validity of S4, and suitably in the spirit of conventionalism. (shrink)

According to Wittgenstein, mathematics is embedded in, and partly constituting, a form of life. Hence, to imagine different, alternative forms of elementary mathematics, we should have to imagine different practices, different forms of life in which they could play a role. If we tried to imagine a radically different arithmetic we should think either of a strange world or of people acting and responding in very peculiar ways. If such was their practice, a calculus expressing the norms of representation they (...) applied could not be called false. Rather, our criticism could only be to dismiss such a practice as foolish and to dismiss their norms as too different from ours to be called ‘mathematics’. (shrink)

This article offers an explanation of perhaps Wittgenstein’s strangest and least intuitive thesis – the semantical mutation thesis – according to which one can never answer a mathematical conjecture because the new proof alters the very meanings of the terms involved in the original question. Instead of basing our justification on the distinction between mere calculation and proofs of isolated propositions, characteristic of Wittgenstein’s intermediary period, we generalize it to include conjectures involving effective procedures as well.

I argue for the Wittgensteinian thesis that mathematical statements are expressions of norms, rather than descriptions of the world. An expression of a norm is a statement like a promise or a New Year's resolution, which says that someone is committed or entitled to a certain line of action. A expression of a norm is not a mere description of a regularity of human behavior, nor is it merely a descriptive statement which happens to entail a norms. The view can (...) be thought of as a sort of logicism for the logical expressivist---a person who believes that the purpose of logical language is to make explicit commitments and entitlements that are implicit in ordinary practice. The thesis that mathematical statements are expression of norms is a kind of logicism, not because it says that mathematics can be reduced to logic, but because it says that mathematical statements play the same role as logical statements. ;I contrast my position with two sets of views, an empiricist view, which says that mathematical knowledge is acquired and justified through experience, and a cluster of nativist and apriorist views, which say that mathematical knowledge is either hardwired into the human brain, or justified a priori, or both. To develop the empiricist view, I look at the work of Kitcher and Mill, arguing that although their ideas can withstand the criticisms brought against empiricism by Frege and others, they cannot reply to a version of the critique brought by Wittgenstein in the Remarks on the Foundations of Mathematics. To develop the nativist and apriorist views, I look at the work of contemporary developmental psychologists, like Gelman and Gallistel and Karen Wynn, as well as the work of philosophers who advocate the existence of a mathematical intuition, such as Kant, Husserl, and Parsons. After clarifying the definitions of "innate" and "a priori," I argue that the mechanisms proposed by the nativists cannot bring knowledge, and the existence of the mechanisms proposed by the apriorists is not supported by the arguments they give. (shrink)

outrageous remarks about contradictions. Perhaps the most striking remark he makes is that they are not false. This claim first appears in his early notebooks (Wittgenstein 1960, p.108). In the Tractatus, Wittgenstein argued that contradictions (like tautologies) are not statements (Sätze) and hence are not false (or true). This is a consequence of his theory that genuine statements are pictures.