This chapter discusses formal theories of truth: the redundancy theory and its ilk, distinguished by the attempt to characterize truth in terms of its structural properties, in the context of the position adopted by Putnam in his John Dewey Lectures, here styled ‘Common-sense Realism’. This position is described, combining two principles called the Thesis of the Internality and the Thesis of World-Embeddedness, with a formal account of truth. It is argued that Common-sense Realism, along (...) with all theories comprising a formal account of truth, should be committed to the flames, because they are cut off from exploiting the Fregean model of meaning, based on a recursion on truth. (shrink)

Three leading philosopher-logicians present a clear and concise overview of formal theories of truth, explaining key logical techniques. Truth is as central topic in philosophy: formal theories study the connections between truth and logic, including the intriguing challenges presented by paradoxes like the Liar.

Why is it that even strong formal theories of truth fail to prove their own consistency? Although Field has addressed this question for many theories of truth, I argue that there is an important and attractive class of theories of truth that he omitted in his analysis. Such theories cannot prove that all their axioms are true, though unlike many of the cases Field considers, they do not prove that any of their (...) axioms are false or that any of their rules of inference are not truth preserving. I argue that it is the fact that such theories are not finitely axiomatizable that stops them from proving their own consistency. (shrink)

Recent work on formal theories of truth has revived an approach, due originally to Tarski, on which syntax and truth theories are sharply distinguished—‘disentangled’—from mathematical base theories. In this paper, we defend a novel philosophical constraint on disentangled theories. We argue that these theories must be epistemically stable: they must possess an intrinsic motivation justifying no strictly stronger theory. In a disentangled setting, even if the base and the syntax theory are individually (...) stable, they may be jointly unstable. We contend that this flaw afflicts many proposals discussed in the literature; we defend a new, stable disentangled theory, double second-order arithmetic. (shrink)

The paradoxes about truth are the subject of extensive research. Developing an original approach, this book argues that we should diverge from classical logic and presents a number of formal theories of truth. Also included is a beginner-friendly introduction to semantic paradoxes, and a discussion of alternative non-classical theories.

This article outlines what a formal theory of truth should be like, at least at first glance. As not all of the stated constraints can be satisfied at the same time, in view of notorious semantic paradoxes such as the Liar paradox, we consider the maximal consistent combinations of these desiderata and compare their relative advantages and disadvantages.

The main aim of our paper was to present three formal tools for comparing various axiomatic theories of truth. In Section 2 we aimed at showing that there are indeed many different approaches to defining a set of axioms for the notion of truth. In Section 3 we introduced three different \measures of strength" of axiomatic theories of truth, i.e. three reflexive and transitive relations on the set of axiomatic theories of truth. (...) We have explained the intuition behind each of them. The three relations were called : Fujimoto definability, model-theoretical strength, proof-theoretical strength. Then in the last section we described how they order the truth theories introduced in Section 2. We observed that theories made equivalent by the coarser relation can be strictly ordered by the next one. (shrink)

A formal theory of truth, alternative to tarski's 'orthodox' theory, based on truth-value gaps, is presented. the theory is proposed as a fairly plausible model for natural language and as one which allows rigorous definitions to be given for various intuitive concepts, such as those of 'grounded' and 'paradoxical' sentences.

The Semantic Theory of Truth The semantic theory of truth was developed by Alfred Tarski in the 1930s. The theory has two separate, although interconnected, aspects. First, it is a formal mathematical theory of truth as a central concept of model theory, one of the most important branches of mathematical logic. Second, it … Continue reading Semantic Theory of Truth →.

Quine argues, in “On the Nature of Moral Values” that a coherence theory of truth is the “lot of ethics”. In this paper, I do a bit of work from within Quinean theory. Specifically, I explore precisely what a coherence theory of truth in ethics might look like and what it might imply for the study of normative value theory generally. The first section of the paper is dedicated to the exposition of a formally correct coherence truth (...) predicate, the possibility of which has been the subject of some skepticism. In the final two sections of the paper, I claim that a coherence theory in ethics does not reduce the practice of moral inquiry to absurdity, in practice as well as in principle. (shrink)

Formal theories, as in logic and mathematics, are sets of sentences closed under logical consequence. Philosophical theories, like scientific theories, are often far less formal. There are many axiomatic theories of the truth predicate for certain formal languages; on analogy with these, some philosophers (most notably Paul Horwich) have proposed axiomatic theories of the property of truth. Though in many ways similar to logical theories, axiomatic theories of (...) class='Hi'>truth must be different in several nontrivial ways. I explore what an axiomatic theory of truth would look like. Because Horwich’s is the most prominent, I examine his theory and argue that it fails as a theory of truth. Such a theory is adequate if, given a suitable base theory, every fact about truth is a consequence of the axioms of the theory. I show, using an argument analogous to Gödel’s incompleteness proofs, that no axiomatic theory of truth could ever be adequate. I also argue that a certain class of generalizations cannot be consequences of the theory. (shrink)

T-biconditionals have often been regarded as insufficient as axioms for truth. This verdict is based on Tarski’s observation that the typed T-sentences suffer from deductive weakness. As indicated by McGee, the situation might change radically if we consider type-free disquotational theories of truth. However, finding a well-motivated set of untyped T-biconditionals that is consistent and recursively enumerable has proven to be very difficult. Moreover, some authors ) have argued that any solution to the semantic paradoxes necessarily involves (...) ‘inflationary’ means, thus spelling doom to deflationist and minimalist truth theories in particular. The situation is indeed worrisome as formal theories of minimalist truth are missing so far. This makes it very hard to properly evaluate the tenets of minimalism. In the present article, we will show how to find safe instances of the T-schema just by relying on syntactic features of the sentences of our language—in particular, we will explore Quine’s idea of stratification. Based on that, we will introduce some disquotational truth theories that are deductively very strong. (shrink)

A preliminary statement of the formal theory of the truthmaker relation advanced in the paper “Truth-makers” (Mulligan, Simons and Smith) in 1984. Correspondence theories of truth have. I give a brief account of some more or less obvious formal characteristics of this almost forgotten basic truthmaker relation. I then attempt to show how this account may be extended to provide elements of a theory of truth which is in keeping with the spirit of Wittgenstein’s (...) Tractatus. (shrink)

SummaryIn developing his claim that meaning cannot be understood independently of truth, Donald Davidson argues that a theory of meaning will take the form of a Tarskian theory of truth. In this essay I seek to describe more fully the structure of a Davidsonian theory of meaning and the extent to which Davidson modifies Tarski's account. 1 consider and reject John Foster's claim that Davidson takes, or should take, truth as a formal primitive, and argue that (...) it is Davidson's principle of charity which plays the essential role in giving theories of truth empirical application. (shrink)

The liar and kindred paradoxes show that we can derive contradictions if our language possesses sentences lending themselves to paradox and we reason classically from schema about truth: Sis true iffp, where the letter p is to be replaced with a sentence and the letter S with a name of that sentence. This article presents a theory of truth that keeps at the expense of classical logic. The theory is couched in a language that possesses paradoxical sentences. It (...) incorporates all the instances of the analogue of for that language and also includes other platitudes about truth. The theory avoids contradiction because its logical framework is an appropriately constructed nonclassical propositional logic. The logic and the theory are different from others that have been proposed for keeping, and the methods used in the main proofs are novel. (shrink)

412 THE JOURNAL OF PHILOSOPHY There are theories that try, in my opinion unsuccessfully, to do just this. Tarski's theory, which restricts itself to cases in which truth is predicated of sentences of certain formal languages, is not one of them. Thus, Tarski cannot be seen.

Kripke’s work on modal logic has been immensely influential. It hardly needs remarking that this is not his only work. Here we address his pioneering applications of fixpoint constructions to the theory of truth, and related work by others. In his fundamental paper on this he explicitly described a modal version, applying a fixpoint construction world by world within a modal frame. This can certainly be carried out, and doubtless has been somewhere. Others have suggested a variety of other (...) extensions such as using the unit interval as the underlying space of truth values, or using a four valued logic instead of three, or various combinations of these. When many similar formal constructions have been proposed, one naturally asks what is the common core. Is there some setting in which things can be proved once and for all, with the various specific proposals seen as applications of this common core. In fact this is the case, with bilattices providing the desired structure. Much of such a development has already appeared in some form or other. It is the purpose of this article to bring everything together, and also add a few things. We present general results that, more or less, have everything currently in the fixpoint literature as special cases. Fortunately this does not make things more complicated, since the underlying proofs are essentially the same as they have always been. It is just that they are being carried out in generality rather than in specificity. (shrink)

Any "classical" theory of truth will satisfy tarski's criterion ("p" is true if and only if p), And the principle of bivalence (every proposition is either true or false). A non-Classical theory may be obtained by rejecting these principles: - in fact it is shown that rejection of the second entails rejection of the first. If the resulting non-Classical theory is formalized, A system structurally isomorphic to either s4 or s5 is obtained. An attempt is made to show that (...) the essential insights of intuitionist logic may be preserved if we replace their complex and in many respects "unintuitive" propositional logic by a theory of truth which is non-Classical in the sense described above. (shrink)

We argue that distinct conditionals—conditionals that are governed by different logics—are needed to formalize the rules of Truth Introduction and Truth Elimination. We show that revision theory, when enriched with the new conditionals, yields an attractive theory of truth. We go on to compare this theory with one recently proposed by Hartry Field.

The aim of this dissertation is to offer and defend a correspondence theory of truth. I begin by critically examining the coherence, pragmatic, simple, redundancy, disquotational, minimal, and prosentential theories of truth. Special attention is paid to several versions of disquotationalism, whose plausibility has led to its fairly constant support since the pioneering work of Alfred Tarski, through that by W. V. Quine, and recently in the work of Paul Horwich. I argue that none of these (...) class='Hi'>theories meets the correspondence intuition---that a true sentence or proposition in some way corresponds to reality---despite the explicit claims by each to capture this intuition. I distinguish six versions of the correspondence theory, and defend two against traditional objections, standardly taken as decisive against them, and show, plainly, that these two theories capture the correspondence intuition. Due to the importance of meeting this intuition, only these two theories stands a chance of being a satisfactory theory of truth. I argue that the version of the correspondence theory incorporating a simple semantic representation relation is preferable to its rival, for which the representation relation is complex. I present and argue for a novel version of this correspondence theory according to which truth is a correspondence property sensitive to semantic context. One consequence of this context-sensitivity is that an ungrounded sentence does not express a proposition. In addition to accounting for the similarity between the Liar and Truth-Teller sentences, this theory of truth is immune to the Liar Paradox, including empirical versions. It is argued that the Liar Paradox is devastating to all of the other theories above, and even formal theories of truth designed to solve it, such as the revision and vagueness theories. Customized versions of the Liar Paradox besetting this theory are handled by its context-sensitivity, and by enforcing the distinction between truth and truth value. This same pair of considerations also yields solutions to Lob's Paradox and Grelling's Paradox. Arguments similar to those given to defend this correspondence theory show that with one minor alteration, Kripke's fixed point theory may be used to model this correspondence notion of truth. (shrink)

This work attempts to develop a workable formal theory of coherence that avoids the objections traditionally advanced against the earliest versions of the theory. Basically it construes the coherence theory as a criterial rather than definitional approach to truth, i.e., as furnishing a criterion rather than a definition of truth. The problem of criterion is seen as a problem not of guaranteeing but of authorizing criterion. Coherence is a criterion applying to a set of propositions that satisfies (...) the conditions of consistency and connectiveness of the systemic sort. A detailed logical machinery is developed. The pivotal concept is the notion of data as a truth-candidate, "a proposition to be taken not as true, but as potentially or presumptively true.". (shrink)

Part 1 – Formal Development of Theory .................................................................................................4..

John Dewey’s theory of truth is widely viewed as proposing to substitute “warranted assertibility” for “truth,” a proposal that has faced serious objections since the late 1930s. By examining Dewey’s theory in its historical context – and, in particular, by drawing parallels with Otto Neurath’s concurrent attempts to develop a non-correspondence, non-formal theory of truth – I aim to shed light on Dewey’s underlying objectives. Dewey and Neurath were well-known to each other and, as their writing (...) and correspondence make clear, they took similar paths over the mid-century philosophical terrain. I conclude that Dewey’s account of truth is more principled, and more relevant to historical debates, than it first appears. (shrink)

We present a theory VF of partial truth over Peano arithmetic and we prove that VF and ID 1 have the same arithmetical content. The semantics of VF is inspired by van Fraassen's notion of supervaluation.

Two concepts of truth as correspondence of ideas with facts are analyzed. One of them is the thought-external fact relation, and the other is the fact-proposition one. The two maps are then composed, and the resulting map is assumed to formalize the concept of truth as adequacy or correspondence of ideas to facts. Besides, some desiderata for a correspondence theory of partial truth are proposed. Finally, the truth criteria employed in science and technology are recalled.

Tim Maudlin’s Truth and Paradox offers a theory of truth that arises from a foundationalist picture of language. The picture is attractive, and Maudlin builds on it courageously. From the formal point of view, the theory of truth that emerges is, as Maudlin observes, nothing other than the least-fixed-point theory of Saul Kripke. From the philosophical point of view, however, the differences between Maudlin’s and Kripke’s theories are large. It is these differences that lead Maudlin (...) to claim advantages that Kripke did not claim for his own theory. Maudlin says that his theory demands no object-language/metalanguage distinction, that he has “developed a theory of truth for a language that can serve as its own metalanguage.” He promises early on that his theory will be “more adequate to our actual practice of reasoning about truth [than revision and other fixed-point theories].” And he claims that the language he has constructed is expressively complete. (shrink)

The present article purports to show that the protocol sentence debate, pursued by some leading members of the Vienna Circle in the mid-1930s, was essentially a controversy over the explanation and the real significance of the concept of truth. It is further shown that the fundamental issue underlying the discussions about the concept of truth was the relationship between form and content, as well as between logic/language and the world. R. Carnap was the philosopher who most explicitly and (...) systematically attempted to come to grips with this problem. It is shown that the form-content distinction pervades the three most important phases of Carnap's philosophical development: the structuralist (in Der logische Aufbau der Welt), the syntactical and the semantical. His final semantical stance is essentially determined by the concept of linguistic frameworks. The article purports to demonstrate that this concept cannot be dispensed with in philosophy, but that Carnap failed to work out its ontological implications. Finally, the concept of an internal ontology is briefly delineated. (shrink)

This article examines Kevin Scharp’s formal solution to the alethic paradoxes, ADT, which stands for ascending and descending truth. One of the main supposed benefits of ADT over its competitors is that it alone can validate the uses of truth concepts in theoretical contexts, such as truth-theoretic semantics. The appendixes contain a new consistency proof for ADT, and additionally show that it is conservative. As a result of its conservativity, the article argues that ADT faces a (...) problem in accounting for certain mathematical uses of truth. Thus, Scharp’s theory needs to be amended in order to fulfill its aim of replicating all substantive uses of truth. (shrink)

Abstract:In the writings of the Chinese Madhyamaka master Jizang (549–623 c.e.), we often read arguments that deduce universal affirmation from universal negation. In previous scholarship, this seemingly paradoxical reasoning was often explained by ascribing to Jizang a type of transcendental realism—the view that reality transcends our ordinary language, logic, and reason—and reading it as his unique way of capturing such a transcendental nature of reality. More recently, an attempt at formalizing this transcendental realist interpretation of Jizang was made by Yasuo (...) Deguchi, who suggests that Jizang could have been tinkering with a type of dialethism. This article challenges the transcendental realist interpretation of Jizang by studying strong anti-realist tendencies found across his writings, and proposes a way to understand his deduction of universal affirmation from universal negation within the boundaries of ordinary reasoning and coherently with his anti-realist philosophy by introducing the modalities of "categorical truth" and "conditional truth.". (shrink)

The article is about one of the vital problem for analytic philosophy which is how to define truth value for sentences which include their own truth predicate. The aim of the article is to determine Saul Kripke’s approach to widen epistemological truth to create a systemic model of truth. Despite a lot of work on the subject, the theme of truth is no less relevant to modern philosophy. With the help of S. Kripke’s article “Outline (...) of the Theory of Truth” and R. L. Kirkham’s work “Theories of Truth: A Critical Introduction” the author tried to represent a non-classical approach which is now known as Saul Kripke’s truth value gaps theory. Considering his solving of the Liar Paradox, as well as the Strenghened Liar, it is obvious that there could be the circumstances (or facts) that make sentences have no truth value. In that case the solving of the paradox attracts Kleene’s non-classical three-valued logic which contains the third way and the solution falls into the gap between truth and falsity. Hence there are no relevant and full satisfactory ways to solve the Liar’s Paradox by the language-levels ap- proach. The task consists in an extension of the approach to natural languages and elimination of an ad hoc element as well. Besides that, the language-levels approach refers to the speaker that means that only the last one is allowed to define the hierarchy of the levels and truth value of sentence, but often he does not know what level he is speaking of. As Kripke stated, contingent facts can lead to a paradox which isn’t allowed for a logical point of view. However usage of mathematical apparatus allows the theory in question to be universalized and moreover paves the way to futher epistemological develop- ment of the problem in question. As Kripke’s theory is formalized and presented as a functional series, it gives access to a system model of truth whose elements would be epistemological theories (concepts) of truth. Such a model, for instance, confirms the validity of the deflationary concept of truth. Refs 7. (shrink)

We expand on the fixed point semantic approach of Kripke via the addition of two unary intensional operators: a paradoxicality operator Π where Π(Φ) is true at a fixed point if and only if Φ is paradoxical (i.e., if and only if Φ receives the third, non-classical value on all fixed points that extend the current fixed point), and an unbounded truth operator Υ⊤ where Υ⊤(Φ) is true at a fixed point if and only if any fixed point extending (...) the current fixed point can be extended to one on which Φ receives the value true. We prove a generalized version of Kripke’s fixed point theorem guaranteeing the existence of models of this new language, as well as an expressive completeness result. We conclude with an exploration of the significant improvements in expressive power that result from the addition of these new operators, and we precisely identify what still cannot be said on this intensional extension of the Kripkean framework. (shrink)

Tarski's definition of truth has rehabilitated the application of the word "true" to sentences of formalized languages. But a correspondence theory according to which a sentence is true if, And only if, It is related in the peculiar way of correspondence to the facts, Is incompatible with tarski's definition. Actually no theory of truth, Which claims to make proper assertions about sentences when calling them true, Is compatible with tarski's definition. Hence they all have to find their own (...) solution to the problem of the semantical antinomies and have to explain what it means to say that sentences are true. (shrink)

In this book, Yaqub describes a simple conception of truth and shows that it yields a semantical theory that accommodates the whole range of our seemingly conflicting intuitions about truth. This conception takes the Tarskian biconditionals as correctly and completely defining the notion of truth. The semantical theory, which is called the revision theory, that emerges from this conception paints a metaphysical picture of truth as a property whose applicability is given by a revision process rather (...) than by a fixed extension. The main advantage of this revision process is its ability to explain why truth seems in many cases almost redundant, in others substantial, and yet in others paradoxical. Yaub offers a comprehensive defense of the revision theory of truth by developing consistent and adequate formal semantics for languages in which all sorts of problematic sentences can be constructed. Yaqub concludes by introducing a logic of truth that further demonstrates the adequacy of the revision theory. (shrink)

As the title suggests, this paper aims at surveying some recent advances in the theory of formal truth. It contains an account of the debate concerning the deflationist approach to truth, according to which truth is a ‘thin’ notion in that it should involve no assumption of whatsoever nature. We review here the main issues that were comprised by the discussion accompanying the attempts of translating this idea into logical terms. In the second half of the (...) paper, we focus on a recent theory of truth proposed by Hartry Field, a former ‘champion’ of the deflationary approach. We then discuss it both with respect to the previous conceptual account, and to some further observation concerning the truth–as–revision machinery that this theory can be proved to implicitly make use of. (shrink)

Many commentators on Alfred Tarski have, following Hartry Field, claimed that Tarski's truth-definition was motivated by physicalism—the doctrine that all facts, including semantic facts, must be reducible to physical facts. I claim, instead, that Tarski did not aim to reduce semantic facts to physical ones. Thus, Field's criticism that Tarski's truth-definition fails to fulfill physicalist ambitions does not reveal Tarski to be inconsistent, since Tarski's goal is not to vindicate physicalism. I argue that Tarski's only published remarks that (...) speak approvingly of physicalism were written in unusual circumstances: Tarski was likely attempting to appease an audience of physicalists that he viewed as hostile to his ideas. In later sections I develop positive accounts of: (1) Tarski's reduction of semantic concepts; (2) Tarski's motivation to develop formal semantics in the particular way he does; and (3) the role physicalism plays in Tarski's thought. (shrink)

This book provides philosophers and logicians with a broad spectrum of views on contemporary research on the problem of deduction, its justification and explanation. The variety of distinct approaches exemplified by the single chapters allows for a dialogue between perspectives that, usually, barely communicate with each other. The contributions concern (in a possibly intertwined way) three major perspectives in logic: philosophical, historical, formal. The philosophical perspective has to do with the relationship between deductive validity and truth, and questions (...) the alleged conclusiveness of deduction and its epistemic contribution. It also discusses the role of linguistic acts in deductive practice, and provides a cognitive-didactic contribution on how we may learn through deduction. In the historical perspective, the contributions discuss the ideas of some major historical figures, such as Bolzano, Girard, Gödel, and Peano. Finally, in the formal perspective, the mathematics of deduction is dealt with mainly from an intuitionistic-constructivist or proof-theoretic point of view, with focus on “ecumenic” or internalistic approaches to logical validity, on the nature and identity of proofs, and on dialogical setups. Chapter [14] is available open access under a Creative Commons Attribution 4.0 International License via link.springer.com. (shrink)

The nature of truth has occupied philosophers since the very beginning of the field. Our goal is to clarify the notion of scientific truth, in particular the notion of partial truth of facts. Our strategy consists to brake the problem into smaller, more manageable, questions. Thus, we distinguish the truth of a scientific theory, what we call the "global" truth value of a theory, from the truth of a particular scientific proposition, what we call (...) the "local" truth values of a theory. We will present a new local theory of partial truth and will have few things to say about the global level. Moreover, we will also introduce some purely formal results, the most important being the introduction of a new class of algebraic structures which have some interesting connections with classical logic. (shrink)

We study, in an abstract and general framework, formal representations of dependence and groundedness which occur in semantic theories of truth. Our goals are: (a) to relate the different ways in which groundedness is defined according to the way dependence is represented; and (b) to represent different notions of dependence as instances of a suitable generalisation of the mathematical notion of functional dependence.

(1) The form of scientific probability sentences is given unambiguously for the first time by quantum mechanics (form (II); all scientific probability statements can be written in this form. (2) The rules of transformation are also determined by quantum mechanics they agree with the axioms given by Reichenbach (1), p. 118. (3) Frequency interpretation agreeing with the statistical tests used in scientific practice can be given in the frame of truth-semantics at least aa a first approximation.

This is part two of a two-part paper in which we develop an axiomatic theory of the relation of partial ground. The main novelty of the paper is the of use of a binary ground predicate rather than an operator to formalize ground. In this part of the paper, we extend the base theory of the first part of the paper with hierarchically typed truth-predicates and principles about the interaction of partial ground and truth. We show that our (...) theory is a proof-theoretically conservative extension of the ramified theory of positive truth up to. (shrink)

Can Tarski's definition of truth be taken to be an analysis of truth – i.e., a method of defining formal truth predicates that are capable of playing the role of truth in all theoretical contexts in which that notion is needed? It is argued that although Tarski's truth predicates can play many of the roles demanded of truth, they cannot play the role of truth in theories of meaning and interpretation. Crucial (...) to the argument is the observation that there is a conceptual connection between our ordinary notions of truth and meaning, in virtue of which statements of the truth conditions of sentences provide some information about their meanings. Since there is no corresponding connection between Tarski's notion of truth and the notion of meaning, statements of the Tarski‐truth conditions of sentences provide no information about meaning. The chapter closes with a detailed defense of Tarski's model‐theoretic analysis of logical truth and logical consequence against John Etchemendy's objections to it. (shrink)

The thesis critically examines the question of the philosophical coherence of finitism, the view which seeks to interpret mathematics without postulating an actual infinity of mathematical objects. It is argued that a widely accepted characterization of finitism, most recently expounded by Tait, is inadequate, and a new characterization based on the notion of elementary abstraction is proposed. It is further argued that the notion of elementary abstraction better explains the bearing of Godel's incompleteness theorems on the issue of the coherence (...) of finitism. By abstraction is meant a procedure by which one recognizes or establishes that some infinite process exhibits a distinctive uniformity. If the procedure does not require one to conceive of the integers in any other way than as the result of simple iterations, we call such abstraction elementary. Some six different formal models exploring a variety of different ways in which this notion can be made precise are proposed as possible formal characterizations of finitistic truth. It is proved that all these different models are equivalent with respect to finitistically meaningful sentences. This is taken as strong evidence that the notion of elementary abstraction is determinate enough to provide a basis for a coherent philosophical formulation of finitism. (shrink)

I defend a conception of Logic as normative for the sort of activities in which inferences super-vene, namely, reasoning and arguing. Toulmin’s criticism of formal logic will be our framework to shape the idea that in order to make sense of Logic as normative, we should con-ceive it as a discipline devoted to the layout of arguments, understood as the representations of the semantic, truth relevant, properties of the inferences that we make in arguing and reason-ing.

In the Tractatus, Wittgenstein maintains that “The world is all that is the case.” Some philosophers have seen an advantage in introducing into a formal language either a constant which will represent the world, or an operator, e.g., ‘Max’, such that indicates that p gives a complete description of the actual world, of the world at some instant of time, or of a possible world. Such propositions are called world propositions, possible world propositions, or maximal propositions. For us, a (...) maximal proposition is a possible world proposition; it gives a complete description of one way the world might be. A maximal proposition p is not logically false, and for any proposition q, either p entails q or p entails not-q. (shrink)