Understandably absorbed in technical details, discussion of the semantic paradoxes risks losing sight of broad methodological principles. This chapter sketches a general approach to the comparison of rival logics, and applies it to argue that revision of classical propositional logic has much higher costs than its proponents typically recognize.

ABSTRACTAndrew Bacon, Matti Eklund, and Patrick Greenough have individually proposed objections to the project in my book, Replacing Truth. Briefly, the book outlines a conceptual engineering project – our defective concept of truth is replaced for certain purposes with a team of concepts that can do some of the jobs we thought truth could do. Here, I respond to their objections and develop the views expressed in Replacing Truth in various ways.

Philosophical arguments usually are and nearly always should be abductive. Across many areas, philosophers are starting to recognize that often the best we can do in theorizing some phenomena is put forward our best overall account of it, warts and all. This is especially true in esoteric areas like logic, aesthetics, mathematics, and morality where the data to be explained is often based in our stubborn intuitions. -/- While this methodological shift is welcome, it's not without problems. Abductive arguments involve (...) significant theoretical resources which themselves can be part of what's being disputed. This means that we will sometimes find otherwise good arguments which suggest their own grounds are problematic. In particular, sometimes revising our beliefs on the basis of such an argument can undermine the very justification we used in that argument. -/- This feature, which I'll call self-effacingness, occurs most dramatically in arguments against our standing views on the esoteric subject matters mentioned above: logic, mathematics, aesthetics, and morality. This is because these subject matters all play a role in how we reason abductively. This isn't an idle fact; we can resist some challenges to our standing beliefs about these subject matters exactly because the challenges are self-effacing. The self-effacing character of certain arguments is thus both a benefit and limitation of the abductive turn and deserves serious attention. I aim to give it the attention it deserves. (shrink)

According to an old and attractive view, vagueness must be eliminated before semantic notions — truth, implication, and so on — may be applied. This view was accepted by Frege, but is rarely defended nowadays.1 This..

The criterion of truth is the measure of the truthfulness and reliability of our knowledge. It is also the basis for determining the correctness of our concepts and how much our perceptions, ideas, and concepts accord with objective reality. Idealism holds to the idea that the criterion of truth does not involve the integration between theory as created by human intelligence and objective reality, but rather that the criterion of truth involves the "clarity and correctness" of perception, viewpoints, and concepts (...) by the subject. For instance, the Machists 1 think that the criterion of truth is experience, however, they neither interpret experience from a materialistic viewpoint, nor view experience as the result of humans interacting with nature as they reform it. The Machists view experience as a summary of perceptions and as the subjective experience of humans. In this sense, perception must be tested by perception itself. In attempting to escape the trap of solipsism , they proposed "collective experience" as the criterion of truth. According to such a view, anything that involves "common significance," that is, anything acknowledged by everyone, is the truth. Lenin exposed the absurdity of idealist theory by pointing out that by following the view of "socially formed experience" it is very easy to consider as normal the most absurd and farcical notions, such as ghosts, for such beliefs are also a form of human "experience." Religion also possesses a "common significance," for innumerable people believe in ghosts and miracles, etc. Nevertheless, religion does not become the truth because of this. The concept of the "criterion of truth" held by the Machists played a dominant role in modern bourgeois philosophy. Jean Jacques Rousseau and John Dewey, along with other reactionaries in philosophy all denied scientific criteria. They would rather that the masses remain ignorant of how to understand and determine the truth. (shrink)

In this paper, we do two things. First, we provide some support for adopting a version of the meaningless strategy with respect to the liar paradox, and, second, we extend that strategy, by providing, albeit tentatively, a solution to that paradox—one that is semantic, rather than logical.

We argue that if Stephen Yablo (2005) is right that philosophers of mathematics ought to endorse a fictionalist view of number-talk, then there is a compelling reason for deflationists about truth to endorse a fictionalist view of truth-talk. More specifically, our claim will be that, for deflationists about truth, Yablo’s argument for mathematical fictionalism can be employed and mounted as an argument for truth-theoretic fictionalism.

What Bar-On and Simmons call 'Conceptual Deflationism' is the thesis that truth is a 'thin' concept in the sense that it is not suited to play any explanatory role in our scientific theorizing. One obvious place it might play such a role is in semantics, so disquotationalists have been widely concerned to argued that 'compositional principles', such as -/- (C) A conjunction is true iff its conjuncts are true -/- are ultimately quite trivial and, more generally, that semantic theorists have (...) misconceived the relation between truth, meaning, and logic. This paper argues, to the contrary, that even such simple compositional principles as (C) have substantial content that cannot be captured by deflationist 'proofs' of them. The key thought is that (C) is supposed, among other things, to affirm the truth-functionality of conjunction and that disquotationalists cannot, ultimately, make sense of truth-functionality. -/- This paper is something of a companion to "The Logical Strength of Compositional Principles". (shrink)

consistent and sufficiently strong system of first-order formal arithmetic fails to decide some independent Gödel sentence. We examine consistent first-order extensions of such systems. Our purpose is to discover what is minimally required by way of such extension in order to be able to prove the Gödel sentence in a non-trivial fashion. The extended methods of formal proof must capture the essentials of the so-called ‘semantical argument’ for the truth of the Gödel sentence. We are concerned to show that the (...) deflationist has at his disposal such extended methods—methods which make no use or mention of a truth-predicate. This consideration leads us to reassess arguments recently advanced—one by Shapiro and another by Ketland—against the deflationist's account of truth. Their main point of agreement is this: they both adduce the Gödel phenomena as motivating a ‘thick’ notion of truth, rather than the deflationist's ‘thin’ notion. But the so-called ‘semantical argument’, which appears to involve a ‘thick’ notion of truth, does not really have to be semantical at all. It is, rather, a reflective argument. And the reflections upon a system that are contained therein are deflationarily licit, expressible without explicit use or mention of a truth-predicate. Thus it would appear that this anti-deflationist objection fails to establish that there has to be more to truth than mere conformity to the disquotational T-schema. (shrink)

I am not a deflationist. I believe that truth and falsity are substantial. The truth of a proposition consists in its having a constructive proof, or truthmaker. The falsity of a proposition consists in its having a constructive disproof, or falsitymaker. Such proofs and disproofs will need to be given modulo acceptable premisses. The choice of these premisses will depend on the discourse in question.

This is a discussion of different ways of working out the idea that the semantic paradoxes show that natural languages are somehow “inconsistent”. I take the workable form of the idea to be that there are expressions such that a necessary condition of understanding them is that one be inclined to accept inconsistent claims (an conception also suggested by Matti Eklund). I then distinguish “simple” from “complex” forms of such views. On a simple theory, such expressions are meaningless, while on (...) a complex theory they are not. I argue that complex theories are incompatible with truth conditional semantics and that simple theories are only coherent when the inconsistent claims are metalingusitic attributions of meaning. I close with a discussion of the version of the simple metalinguistic theory I have defended in “Understanding the Liar” and other papers. (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)

Restrictionism is a response to the Liar and other paradoxes concerning truth. Restrictionists—as I will call proponents of the strategy—respond to these paradoxes by giving up instances of the schema -/- <p> is true iff p. -/- My aim is to show that the current unpopularity of restrictionism is undeserved. I will argue that, whilst cautious versions of the strategy may face serious problems, a radical and previously overlooked version of restrictionism provides a strong and defensible response to the paradoxes.

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.

An intuitive argument for scientific realism suggests that our successes in predicting and intervening would be inexplicable if the theories that generate them were not approximate y true. This argument faces many objections, some of which are briefly addressed in this paper, and one of which is treated in more detail. The focal criticism alleges that appeals to success cannot deliver conclusions that parts of science are true in the sense of truth-as-correspondence that realists prefer. The paper responds to that (...) criticism, in versions proposed by Michael Williams, Michael Levin, and, especiaIly, Paul Horwich, by arguing that critics typically stop at a shallow level of psychological explanation. If we probe more deeply we discover a genuine explanatory role for correspondence truth. (shrink)

An intuitive argument for scientific realism suggests that our successes in predicting and intervening would be inexplicable if the theories that generate them were not approximately true. This argument faces many objections, some of which are briefly addressed in this paper, and one of which is treated in more detail. The focal criticism alleges that appeals to success cannot deliver conclusions that parts of science are true in the sense of truth‐as‐correspondence that realists prefer. The paper responds to that criticism, (...) in versions proposed by Michael Williams, Michael Levin, and, especially, Paul Horwich, by arguing that critics typically stop at a shallow level of psychological explanation. If we probe more deeply we discover a genuine explanatory role for correspondence truth. (shrink)

Inflationists have argued that truth is a causal-explanatory property on the grounds that true belief facilitates practical success: we must postulate truth to explain the practical success of certain actions performed by rational agents. Deflationists, however, have a seductive response. Rather than deny that true belief facilitates practical success, the deflationist maintains that the sole role for truth here is as a device for generalisation. In particular, each individual instance of practical success can be explained only by reference to a (...) relevant instance of a T-schema; the role of truth is just to generalise over these individualised explanations. I present a critical problem for this strategy. Analogues of the deflationist’s individualised explanations can be produced by way of explanation of coincidental instances of practical success where the agent merely has the right false beliefs. By deflationary lights, there is no substantive explanatory difference between such coincidental and non-coincidental instances of practical success. But the non-/coincidental distinction just is an explanatory distinction. The deflationist’s individualised explanations of non-coincidental instances of practical success must therefore be inadequate. However, I argue that the deflationist’s prospects for establishing an explanatory contrast between these cases by supplementing her individualised explanations are, at best, bleak. The inflationist, by contrast, is entitled to the obvious further explanatory premise needed to make sense of the distinction. As such, pending some future deflationary rejoinder, the deflationary construal of the principle that true belief facilitates practical success must be rejected; and with it the deflationary conception of truth. (shrink)

I discuss some problems faced by the meaning‐inconsistency view on the liar and sorites paradoxes which I have elsewhere defended. Most of the discussion is devoted to the question of what a defender of the meaning‐inconsistency view should say about semantic competence.

The article is an extended critical discussion of Kevin Scharp’s Replacing Truth. Scharp’s case for the claim that the concept of truth is inconsistent is criticized, and so is his case for the claim that the concept of truth must be replaced because of its inconsistency.

The main thesis of this paper is that we sometimes are disposed to accept false and even jointly inconsistent claims by virtue of our semantic competence, and that this comes to light in the sorites and liar paradoxes. Among the subsidiary theses are that this is an important source of indeterminacy in truth conditions, that we must revise basic assumptions about semantic competence, and that classical logic and bivalence can be upheld in the face of the sorites paradox.

The T-biconditionals, also known as T-sentences or T-equivalences, play a very prominent role in contemporary work on truth. It is widely held that they are so central to our understanding of truth that conformance with them is indispensable to any account of truth that aspires to be adequate. Even “deflationists” and “inflationists” tend to agree on this point; their debate turns largely on just how central a role these biconditionals can play in a theory of truth. In the present paper, (...) I want to bracket this debate about their “theoretical role” and focus on the T- biconditionals themselves. They are typically presented as entirely unproblematic, as models of simplicity, clarity, and obviousness. I confess that I find them rather more puzzling than that. The main purpose of the paper is to reflect on some of these biconditionals and to survey and explore some doubts one might have about their virtues. (shrink)

Truth-talk exhibits certain features that render it philosophically suspect and motivate a deflationary account. I offer a new formulation of deflationism that explains truth-talk in terms of semantic pretense. This amounts to a fictionalist account of truth-talk but avoids an error-theoretic interpretation and its resulting incoherence. The pretense analysis fits especially well with deflationism’s central commitment, and it handles truth-talk’s unusual features effectively. In particular, this approach suggests an interesting strategy for dealing with the Liar paradox. This version of deflationism (...) has advantages over the formulations currently available in the literature, mainly because it offers a more satisfying account of the generalizing role deflationary views take as truth-talk’s central function. Explaining the notion of truth in terms of pretense generates some special concerns, but none we cannot address through careful consideration of how pretense operates in truth-talk and of the attitudes instances of pretending involve. (shrink)

(Beall ed. The Revenge of the Liar, forthcoming from Oxford University Press) > The main presentation of my approach to the semantic paradoxes. I take them to show that understanding a natural language is sharing a cognitive relation to a logically false semantic theory with other speakers.