Deflationists claim that the truth predicate was introduced into our language merely to full a certain logico-linguistic function. Oddly enough, the question what this function exactly consists in has received little attention. We argue that the best way of understanding the function of the truth predicate is as enabling us to mimic higher-order quantification in a first-order framework. Indeed, one can show that the full simple theory of types is reducible to disquotational principles of truth. Our analysis has important consequences (...) for our understanding of truth. In this paper, we can only touch on one of them: we will argue that the insubstantiality of truth does not imply a conservativity requirement on our best theories of truth. (shrink)

This note is a critical response to Kentaro Fujimoto’s new conservativeness argument about truth, which centres on the notion of finite conjunction. We argue that Fujimoto’s arguments turn on a specific way of formalizing the notions of finite collection and finite conjunction in first-order logic. In particular, by instead formalizing these concepts in a natural way in set theory or in second-order logic, Fujimoto’s new conservativeness argument can be resisted.

Deflationism about truth describes truth as a logical notion. In the present paper, I explore the implication of the alleged logicality of truth from the perspective of axiomatic theories of truth, and argue that the deflationist doctrine of the logicality of truth gives rise to two types of self-undermining arguments against deflationism, which I call the conservativeness argument from logicality and the topic-neutrality argument.

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)

Deflationists argue that ‘true’ is merely a logico-linguistic device for expressing blind ascriptions and infinite generalisations. For this reason, some authors have argued that deflationary truth must be conservative, i.e. that a deflationary theory of truth for a theory S must not entail sentences in S’s language that are not already entailed by S. However, it has been forcefully argued that any adequate theory of truth for S must be non-conservative and that, for this reason, truth cannot be deflationary :493–521, (...) 1998; Ketland in Mind 108:69–94, 1999). We consider two defences of conservative deflationism, respectively proposed by Waxman :429–463, 2017) and Tennant :551–582, 2002), and argue that they are both unsuccessful. In Waxman’s hands, deflationists are committed either to a non-purely expressive notion of truth, or to a conception of mathematics that does not allow them to justifiably exclude non-conservative theories of truth. Tennant’s conservative deflationism fares no better: if deflationist truth must be conservative over arithmetic, it can be shown to collapse into a non-conservative variety of deflationism. (shrink)

This article argues for the compatibility of deflationism and truth-conditional semantic theories. I begin by focusing on an argument due to Dorit Bar-On, Claire Horisk, and William Lycan for incompatibility, arguing that their argument relies on an ambiguity between two senses of the expression ‘is at least.’ I go on to show how the disambiguated arguments have different consequences for the deflationist, and argue that no conclusions are established that the deflationist cannot accommodate. I then respond to some objections and (...) gesture at a more general defense of the compatibility claim. (shrink)

Deflationism about truth, what is often simply called “deflationism”, is really not so much a theory of truth in the traditional sense, as it is a different, newer sort of approach to the topic. Traditional theories of truth are part of a philosophical debate about the nature of a supposed property of truth. Philosophers offering such theories often make suggestions like the following: truth consists in correspondence to the facts; truth consists in coherence with a set of beliefs or propositions; (...) truth is what is acceptable in the ideal limit of inquiry. According to deflationists, such suggestions are mistaken, and, moreover, they all share a common mistake. The common mistake is to assume that truth has a nature of the kind that philosophers might find out about and develop theories of. The main idea of the deflationary approach is (a) that all that can be significantly said about truth is exhausted by an account of the role of the expression ‘true’ or of the concept of truth in our talk and thought, and (b) that, by contrast with what traditional views assume, this role is neither metaphysically substantive nor explanatory. For example, according to deflationary accounts, to say that ‘snow is white’ is true, or that it is true that snow is white, is in some sense strongly equivalent to saying simply that snow is white, and this, according to the deflationary approach, is all that can be said significantly about the truth of ‘snow is white’. Philosophers looking for some underlying nature of some truth property that is attributed with the use of the expression ‘true’ are bound to be frustrated, the deflationist says, because they are looking for something that isn’t there. Deflationism comprises a variety of different versions, each of which have gone by different names, including at least the following: disquotationalism, minimalism, prosententialism, the redundancy theory, the disappearance theory, the no-truth theory. There has not always been terminological consensus in the literature about how to use these labels: sometimes they have been used interchangeably; sometimes they have been used to mark distinctions between different developments of the same general approach. The actual variety of deflationary views has not always been clear in discussions of this approach, especially in the earlier literature, where important differences are occasionally missed. To help clear this up, we will use ‘deflationism’ to denote the general approach we want to discuss and reserve other names for specific versions of that approach. (shrink)

Soundness Arguments for the consistency of a (mathematical) theory S aim to show that S is consistent by first showing or employing the fact that S is sound, i.e., that all theorems of S are true. Although soundness arguments are virtually unanimously accepted as valid and sound for most of our accepted theories, philosophers disagree about their epistemic value, i.e., about whether such arguments can be employed to improve our epistemic situation concerning questions of consistency. This article provides a (partial) (...) negative answer to this question and argues that soundness arguments cannot be employed to justify their conclusion. Additionally, soundness arguments are unconvincing; they cannot be employed to overcome reasonable open-mindedness about their conclusion. (shrink)

Truth is often considered to be a logico-linguistic tool for expressing indirect endorsements and infinite conjunctions. In this article, I will point out another logico-linguistic function of truth: to enable and validate what I call a blind argument, namely, an argument that involves indirectly endorsed statements. Admitting this function among the logico-linguistic functions of truth has some interesting consequences. In particular, it yields a new type of so-called conservativeness argument, which poses a new type of threat to deflationism about truth.