Warrant is “that, whatever precisely it is, which makes the difference between knowledge and mere true belief.” S knows that p, therefore, if and only if S’s belief that p is warranted and p is true. This is a purely formal characterization of warrant. Warrant may, no doubt, be a messy item: a substantive analysis might be full of disjuncts and conjuncts and conditionals and caveats. But if there are true beliefs that are not knowledge, then there is something that (...) all beliefs that are knowledge share, and all merely true beliefs lack. This is warrant. I want to argue that warrant, whatever it is that makes the difference between mere true belief and knowledge, entails truth. (shrink)

In this paper I undermine the Entailment Principle according to which if an entity is a truthmaker for a certain proposition and this proposition entails another, then the entity in question is a truthmaker for the latter proposition. I argue that the two most promising versions of the principle entail the popular but false Conjunction Thesis, namely that a truthmaker for a conjunction is a truthmaker for its conjuncts. One promising version of the principle understands entailment as strict (...) implication but restricts the field of application of the principle to purely contingent truths (i.e. those that contain no necessary proposition at any level of analysis). But a conjunction of purely contingent truths strictly implies its conjuncts. So this version of the principle is committed to the Conjunction Thesis. The same is true of the version of the principle where entailment is understood in the sense of systems T, R, and E of relevant logic, since in these systems conjunctions entail their conjuncts. I argue that the Conjunction Thesis is false because a truthmaker is that in virtue of what a certain proposition is true and it is false that, for example, what the proposition that Peter is a man is true in virtue of is the conjunctive fact that Peter is man and Saturn is a planet (or the facts that Peter is a man and that Saturn is a planet taken together). I also argue against other versions of the principle. (shrink)

Despite recent controversies surrounding the principle that knowledge entails truth (KT), this paper aims to prove that the principle is true. It offers a proof of (KT) in the following sense. It advances a deductively valid argument for (KT), whose premises are, by most lights, obviously true. Moreover, each premise is buttressed by at least two supporting arguments. And finally, all premises and supporting arguments can be rationally accepted by people who don’t already accept (KT).

It is almost universally presumed that knowledge is factive: in order to know that p it must be the case that p is true. This idea is often justified by appealing to knowledge ascriptions and related linguistic phenomena; i.e., an utterance of the form ‘S knows that p, but not-p’ sounds contradictory. In a recent article, Allan Hazlett argues that our ordinary concept of knowledge is not factive. From this it seems to follow that epistemologists cannot appeal to ordinary language (...) to justify the truth condition of knowledge. More significantly, Hazlett claims that epistemologists theorizing about knowledge should not concern themselves with the ordinary concept of knowledge as revealed by knowledge ascriptions and related linguistic phenomena. My paper has two goals: first, to defend the orthodox view that the ordinary concept of knowledge is factive; second, to undermine Hazlett’s claim that epistemologists should not theorize about knowledge on the basis of how ‘knows’ is used in everyday speech. (shrink)

Let ‘warrant’ denote whatever precisely it is that makes the difference between knowledge and mere true belief. A current debate in epistemology asks whether warrant entails truth, i.e., whether (Infallibilism) S’s belief that p is warranted only if p is true. The arguments for infallibilism have come under considerable and, as of yet, unanswered objections. In this paper, I will defend infallibilism. In Part I, I advance a new argument for infallibilism; the basic outline is as follows. Suppose fallibilism (...) is true. An implication of fallibilism is that the property that makes the difference between knowledge and mere belief (which I dub ‘warrant*’) is the conjunctive property being warranted and true . I show that this implication of fallibilism conflicts with an uncontroversial thesis we have learned from reflection on Gettier cases: that nonaccidental truth is a constituent of warrant*. It follows that infallibilism is true. In the second part of the paper, I present and criticize a new argument against infallibilism. The argument states that there are plausible cases where, intuitively, the only thing that is keeping a belief from counting as knowledge is the falsity of that belief. Furthermore, it is plausible that such a belief is warranted and false. So, the argument goes, infallibilism is false. I show that this argument fails. (shrink)

Warrant is that, whatever it is, which makes the difference between knowledge and mere true belief. In "Warrant Entails Truth" (PPR, December 1995), I argued that it is impossible that a false belief be warranted. Sharon Ryan attacked the argument of that paper in her "Does Warrant Entail Truth?" (PPR, March 1996). In "More on Warrant's Entailing Truth" I present arguments for the claim that warrant entails truth that are, I think, significantly more compelling than the (...) arguments of my original "Warrant Entails Truth." This paper responds to Ryan's objections, but it is not merely a reply to Ryan's article. It is, rather, a free-standing defense of warrant's entailing truth that is the product of discussion and argument for over two years with many philosophers, including Ryan, over the arguments contained in my original paper. (shrink)

Although ‘warrant’ has been used to mean something like ‘justified to the degree required for knowledge’, it has recently come to mean something else. Alvin Plantinga has recently used the word ‘warrant’ to mean “that, whatever precisely it is, which makes the difference between knowledge and mere true belief.” So, in Plantinga’s sense of the word, warrant is the justification condition plus some other condition designed to rule out Gettier examples. In almost all cases, reliabilists, foundationalists, and coherentists have not (...) been giving theories about ‘warrant’ in Plantinga’s sense. They have been busy giving theories about justification. In his paper, “Warrant Entails Truth,” Trenton Merricks argues that warrant, in Plantinga’s sense, entails truth. In this paper, I will show that Merricks has not succeeded in showing that warrant entails truth. (shrink)

Several philosophers have recently claimed that if a proposition is cancellable from an uttered sentence then that proposition is not entailed by that uttered sentence. The claim should be a familiar one. It has become a standard device in the philosopher's tool-kit. I argue that this claim is false. There is a kind of entailment—which I call “modal entailment”—that is context-sensitive and, because of this, cancellable. So cancellability does not show that a proposition is not entailed by an (...) uttered sentence. I close the paper by describing an implication this has for a disagreement between J. L. Austin and Grice concerning the relation between felicity and truth. (shrink)

Despite recent controversies surrounding the principle that knowledge entails truth (KT), this paper aims to prove that the principle is true. It offers a proof of (KT) in the following sense. It advances a deductively valid argument for (KT), whose premises are, by most lights, obviously true. Moreover, each premise is buttressed by at least two supporting arguments. And finally, all premises and supporting arguments can be rationally accepted by people who don’t already accept (KT).

It is widely accepted that knowledge is factive. This claim is typically justified linguistically: ascribing knowledge of a falsehood sounds contradictory. But linguistic arguments can be problematic. In a recent article, Brent G. Kyle argues that the factivity of knowledge can be proved deductively, without appeal to ordinary language. I argue, however, that his proof relies on a premise that can only be justified linguistically.

This paper outlines a non-reductive counterfactual account of grounding along interventionist lines, and uses the account to argue that taking grounding seriously requires ascribing non-trivial truth-conditions to a range of counterpossible counterfactuals. This result allows for a diagnosis of a route to scepticism about grounding, as deriving at least in part from scepticism about non-trivial counterpossible truth and falsity.

One strategy for blocking Chalmers's overall case against physicalism has been to deny his claim that showing that phenomenal properties are in some sense physical requires an a priori entailment of the phenomenal truths from the physical ones. Here I avoid this well-trodden ground and argue instead that an a priori entailment of the phenomenal truths from the physical ones does not require an analysis in the Jackson/Chalmers sense. This is to sever the dualist's link between conceptual analysis (...) and a priori entailment by showing that the lack of the former does not imply the absence of the latter. Moreover, given the role of the argument from conceptual analysis in Chalmers's overall case for dualism, undermining that argument effectively undermines that case as a whole in a way that, I'll argue, undermining the conceivability arguments as stand-alone arguments does not. (shrink)

Here is a puzzle, which I learned from Terence Parsons in his “True Contradictions” [8]. First Degree Entailment is a logic which allows for truth value gaps as well as truth value gluts. If you are agnostic between assigning paradoxical sentences gaps and gluts, then this looks no different, in effect, from assigning them a gap value? After all, on both views you end up with a theory that doesn’t commit you to the paradoxical sentence or its (...) negation. How is the fde theory any different from the theory with gaps alone? In this paper, I will present a clear answer to this puzzle – an answer that explains how being agnostic between gaps and gluts is a genuinely different position than admitting gaps alone, by using the formal notion of a bi-theory, and showing that while such positions might agree on what is to be accepted, they differ on what is to be rejected. (shrink)

An exact truthmaker for A is a state which, as well as guaranteeing A’s truth, is wholly relevant to it. States with parts irrelevant to whether A is true do not count as exact truthmakers for A. Giving semantics in this way produces a very unusual consequence relation, on which conjunctions do not entail their conjuncts. This feature makes the resulting logic highly unusual. In this paper, we set out formal semantics for exact truthmaking and characterise the resulting notion (...) of entailment, showing that it is compact and decidable. We then investigate the effect of various restrictions on the semantics. We also formulate a sequent-style proof system for exact entailment and give soundness and completeness results. (shrink)

Mike Almeida recently published a paper entitled “Evil Is Not Evidence,” but that title rather understates his conclusion. He argues that no “states of affairs constitute any (non-trivial) evidence for or against the existence of God” (p. 1, original emphasis) (bare page references are to Almeida, 2022). It of course follows from that that evil is not evidence against the existence of God, but it also follows that apparent design or even direct experience of God are not non-trivial evidence for (...) the existence of God. While his title suggests a conclusion favorable to theists, it might in fact be a poisoned pawn, since his conclusion also entails that arguments from design or religious experience are completely hopeless. Such a radical transformation of the traditional debate between theists and atheists bears scrutinizing. In particular, Almeida appeals to a notion of evidence that I'm going to argue is mistaken. The basic argument I am going to make is that Almeida is taking strict implication to be an evidentially relevant relation. In particular he's embracing one of the paradoxes of strict implication, that a necessary truth is strictly implied by any claim whatever, and he's assuming that not only is the inference valid, pace relevance logics, but that it provides evidence for the implied proposition. I'm going to argue this is a mistake. Even if we grant that the inference is valid, we shouldn't accept that it provides evidence. (shrink)

I argue below for the view that non-moral truths entail moral ones. I first argue that moral claims do have truth values which are objectively true or false. I then argue that this objectivism does not entail non-relativism. I produce a simple possible worlds argument for the entailment view. I then give some examples where p entails q but many intelligent people have thought it does not, and where it does not, but many intelligent people have thought that (...) it does. I also try to evaluate a somewhat neglected argument by Hume. In the final section, I further consider some moral and meta-moral opinions. (shrink)

This paper treats entailment as a subrelation of classical consequence and deducibility. Working with a Gentzen set-sequent system, we define an entailment as a substitution instance of a valid sequent all of whose premisses and conclusions are necessary for its classical validity. We also define a sequent Proof as one in which there are no applications of cut or dilution. The main result is that the entailments are exactly the Provable sequents. There are several important corollaries. Every unsatisfiable (...) set is Provably inconsistent. Every logical consequence of a satisfiable set is Provable therefrom. Thus our system is adequate for ordinary mathematical practice. Moreover, transitivity of Proof fails upon accumulation of Proofs only when the newly combined premisses are inconsistent anyway, or the conclusion is a logical truth. In either case Proofs that show this can be effectively determined from the Proofs given. Thus transitivity fails where it least matters — arguably, where it ought to fail! We show also that entailments hold by virtue of logical form insufficient either to render the premisses inconsistent or to render the conclusion logically true. The Lewis paradoxes are not Provable. Our system is distinct from Anderson and Belnap''s system of first degree entailments, and Johansson''s minimal logic. Although the Curry set paradox is still Provable within naive set theory, our system offers the prospect of a more sensitive paraconsistent reconstruction of mathematics. It may also find applications within the logic of knowledge and belief. (shrink)

My purpose in this paper is to argue that the classical notion of entailment is not suitable for non-bivalent logics, to propose an appropriate alternative and to suggest a generalized entailment notion suitable to bivalent and non-bivalent logics alike. In classical two valued logic, one can not infer a false statement from one that is not false, any more than one can infer from a true statement a statement that is not true. In classical logic in fact preserving (...) truth and preserving non-falsity are one and the same thing. They are not the same in non-bivalent logics however and I will argue that the classical notion of entailment that preserves only truth is not strong enough for such a logic. I will show that if we retain the classical notion of entailment in a logic that has three values, true, false and a third value in between, an inconsistency can be derived that can be resolved only by measures that seriously disable the logic. I will show this for a logic designed to allow for semantic presuppositions, then I will show that we get the same result in any three valued logic with the same value ordering. I will finally suggest how the notion of entailment should be generalized so that this problem may be avoided. The strengthened notion of entailment I am proposing is a conservative extension of the classical notion that preserves not only truth but the order of all values in a logic, so that the value of an entailed statement must alway be at least as great as the value of the sequence of statements entailing it. A notion of entailment this strong or stronger will, I believe, be found to be applicable to non-classical logics generally. In the opinion of Dana Scott, no really workable three valued logic has yet been developed. It is hard to disagree with this. A workable three valued logic however could perhaps be developed however, if we had a notion of entailment suitable to non-bivalent logics. (shrink)

Some argue, following Bertrand Russell, that because general truths are not entailed by particular truths, general facts must be posited to exist in addition to particular facts. I argue on the contrary that because general truths (globally) supervene on particular truths, general facts are not needed in addition to particular facts; indeed, if one accepts the Humean denial of necessary connections between distinct existents, one can further conclude that there are no general facts. When entailment and supervenience do not (...) coincide it is only failure of supervenience, not failure of entailment, that carries ontological import. (shrink)

Robert Audi’s Seeing, Knowing, and Doing argues that knowledge does not entail justification, given a broadly externalist conception of knowledge and an access internalist conception of justification, where justification requires the ability to cite one’s grounds or reasons. On this view, animals and small children can have knowledge while lacking justification. About cases like these and others, Audi concludes that knowledge does not entail justification. But the access internalist sense of “justification” is but one of at least two ordinary senses (...) of the term. On a broader or looser sense, “justification” means “being in the right” where that involves meeting a standard or norm. I argue that the beliefs of animals and small children can then meet standards or norms associated with truth and knowledge such that their beliefs may count as justified in this broader or looser sense. I then question whether knowledge fails to entail justification on this broader sense. (shrink)

The validity of an entailment has nothing to do with whether or not the components are true, false, necessary, or impossible; it has to do solely with whether or not there is a necessary connection between antecedent and consequent. Hence it is a mistake (we feel) to try to build a sieve which will “strain out” entailments from the set of material or strict “implications” present in some system of truth-functions, or of truth-functions with modality. Anderson and (...) Belnap (1962, p. 47). (shrink)

The inferences of contraposition (A ⇒ C ∴ ¬C ⇒ ¬A), the hypothetical syllogism (A ⇒ B, B ⇒ C ∴ A ⇒ C), and others are widely seen as unacceptable for counterfactual conditionals. Adams convincingly argued, however, that these inferences are unacceptable for indicative conditionals as well. He argued that an indicative conditional of form A ⇒ C has assertability conditions instead of truth conditions, and that their assertability ‘goes with’ the conditional probability p(C|A). To account for inferences, (...) Adams developed the notion of probabilistic entailment as an extension of classical entailment. This combined approach (correctly) predicts that contraposition and the hypothetical syllogism are invalid inferences. Perhaps less well-known, however, is that the approach also predicts that the unconditional counterparts of these inferences, e.g., modus tollens (A ⇒ C, ¬C ∴ ¬A), and iterated modus ponens (A ⇒ B, B ⇒ C, A ∴ C) are predicted to be valid. We will argue both by example and by calling to the results from a behavioral experiment (N = 159) that these latter predictions are incorrect if the unconditional premises in these inferences are seen as new information. Then we will discuss Adams’ (1998) dynamic probabilistic entailment relation, and argue that it is problematic. Finally, it will be shown how his dynamic entailment relation can be improved such that the incongruence predicted by Adams’ original system concerning conditionals and their unconditional counterparts are overcome. Finally, it will be argued that the idea behind this new notion of entailment is of more general relevance. (shrink)

Deflationary positions have been defended in many areas of philosophy. Most prominent are semantic deflationism about truth and reference, and meta-ontological deflationism, according to which existence has no deep nature and the standard neo-Quinean approach to ontology is misguided. Although both kinds of views have generated much discussion, surprisingly little attention has been paid to the question of how they relate to each other. Are they independent, is it advisable to hold them all at once, or do they even (...) entail each other? One exception is Amie Thomasson, who has argued that semantic deflationism actually entails meta-ontological deflationism. This is unexpected, since semantic deflationism is usually regarded as much less controversial than meta-ontological deflationism. In our paper, we will argue that Thomasson’s argument fails though, and that the connection between the views is in fact weaker than she makes them out to be. (shrink)

In this paper I examine Chalmers and Jackson’s defence of the a priori entailment thesis, that is, the claim that microphysical truths a priori entail ordinary non-phenomenal truths such as ‘water covers 60% of the Earth surface’, which they use as a premise for an argument against the possibility of a reductive explanation of consciousness. Their argument relies on a certain view about the possession conditions of macroscopic concepts such as WATER, known as ascriptivism. In the paper I distinguish (...) two versions of ascriptivism: reductive versus non-reductive ascriptivism. According to reductive ascriptivism, competent users of a concept have the ability to infer truths involving such concept from lower-level truths, whereas according to non-reductive ascriptivism, all that is required in order to be a competent user of a concept is to be able to infer truths involving that concept from other truths, which need not be lower-level truths. I argue, first, that the a priori entailment thesis is committed to reductive ascriptivism, and secondly, that reductive ascriptivism is problematic because it trivializes the notion of a priori knowledge. Therefore, I conclude that Chalmers and Jackson have not presented a convincing case for the claim that microphysical truths entail ordinary non-phenomenal truths a priori, especially when we understand this claim in the sense that is relevant for their argument against the possibility of a reductive explanation of consciousness. (shrink)

The early thirteenth century tract Ars Meliduna deals with the issue whether categorical propositions entail, or are entailed by, ‘continuing’ propositions, i.e. by implications. From the perspective of modern logic, with implication interpreted as a material, truth-functional connective, the first question has to be answered in the affirmative because, e.g. β entails (α ⊃ β). But conversely (α ⊃ β) ‘normally’ doesn’t entail the truth (or the falsity) of any of the components α, β; hence the second question (...) should be answered in the negative. These results cannot, however, be directly transferred to medieval logic because implication was there usually interpreted as a strict implication. Yet, within the framework of modal logic, one obtains parallel results. In particular, whenever β is necessary, then (α → β) must be true. Furthermore, if (α → β) is itself necessary, then it is entailed by α. Thus, in particular, ‘Socrates is a man’ entails the analytically true implication ‘If Socrates is a man, Socrates is an animal’, and the same premiss also entails the tautological consequent ‘If Socrates is white, Socrates is white’. (shrink)

The essence of the meaning of a declarative sentence is given by stating its truth conditions, and consequently semantics, the study of meaning, must include a theory of truth conditions. Such a theory must not only describe accurately the truth conditions of declarative sentences, it must also answer the question of when two sentences have the same truth conditions. The fundamental semantic relation of having the same truth conditions cannot be ignored by any reasonable theory.This (...) paper is an attempt to find a partial account of this relation by using game theoretical semantics as developed by Hintikka and his followers. The account given will establish a connection between this approach to semantics and the theory of firstdegree entailment formulated by Anderson and Belnap. (shrink)

What is the thesis of determinism? Though it is obvious that in principle there is more than one possible thesis that might be given this name, it seems to be the case that philosophers working on the free will problem have gradually gravitated towards a more-or-less standard definition, minor variations on which can now be found widely scattered through the free will literature. I call it the ‘entailment definition’ and it states, roughly, that determinism is the thesis that for (...) any given time, a complete statement of the facts about that time, together with a complete statement of the laws of nature, entails every truth as to what happens after that time. In this paper, I argue that acceptance of the entailment definition has been a mistake—and that we need a definition of determinism which, by contrast with the entailment definition, makes explicit mention of the notion of natural necessity. (shrink)

The determination argument is supposed to show that a sentence's meaning is at least a truth-condition. This argument is supposed to rest on innocent premises that even a deflationist about truth can accept. The argument comes in two versions: one is metaphysical and the other is epistemological. In this paper we will focus on the epistemological version. We will argue that the apparently innocent first premise of that version of the argument is not as innocent as it seems. (...) If the premise is understood in the sense required for the argument to go through then it should be rejected by a deflationist. (shrink)

This paper discusses the relation between the minimal positive relevant logic B and intersection and union type theories. There is a marvelous coincidence between these very differently motivated research areas. First, we show a perfect fit between the Intersection Type Discipline ITD and the tweaking BT of B, which saves implication and conjunction but drops disjunction . The filter models of the -calculus (and its intimate partner Combinatory Logic CL) of the first author and her coauthors then become theory models (...) of these calculi. (The logician's "theory" is the algebraist's "filter".) The coincidence extends to a dual interpretation of key particles—the subtype translates to provable , type intersection to conjunction , function space to implication, and whole domain to the (trivially added but trivial) truth T. This satisfying ointment contains a fly. For it is right, proper, and to be expected that type union should correspond to the logical disjunction of B. But the simulation of functional application by a fusion (or modus ponens product) operation on theories leaves the key Bubbling lemma of work on ITD unprovable for the -prime theories now appropriate for the modeling. The focus of the present paper lies in an appeal to Harrop theories which are (a) prime and (b) closed under fusion. A version of the Bubbling lemma is then proved for Harrop theories, which accordingly furnish a model of and CL. (shrink)

This article presents an empirical examination of the consequences of the virtual entailment principle proposed by Jean Buridan to resolve the Liar paradox. This principle states that every sentence in natural language implicitly asserts its own truth. Adopting this principle means that the Liar sentence is not paradoxical but false, because its content is contradictory to what is virtually implied. As a result, humans should perceive the Liar sentence the same way as any other false sentence. This solution (...) to the Liar paradox received criticism for making ad hoc claims about the natural language. However, thanks to modern advancements in psychophysiology, it became possible to empirically investigate if the human brain really perceives the Liar sentence like a false sentence. We designed and conducted an experiment to examine brain activity in response to true sentences, false sentences and self-referential sentences. Our results provide support for the Buridan’s hypothesis and show that the Liar sentence is processed by the human brain identically to false sentences, while the Truthteller sentence is perceived identically to true sentences. This agrees with predictions derived from the virtual entailment principle and supports the idea that humans think with the logic of truth—a logic for which the truth is a designated value of its adequate semantics. (shrink)

I consider whether a contradiction may be deducible from the proposition that God does not exist. First, I expose a candidate counterexample to a key premise in Swinburne’s argument against the deducibility of a contradiction from God’s non-existence. Second, I present two new strategies one might use to deduce a contradiction. Both strategies make use of Tarski's T-schema together with developments in other theistic arguments. One argument is a conceptualist argument from necessary truth for a necessary mind, and the (...) other is a two-stage contingency argument for the same conclusion. The purpose of this article is not to decisively defend these arguments, but to expose new territory relevant to investigating the nature of God's necessity. (shrink)

The aim of this paper is to define the logical system Sm4 characterised by the degree of truth-preserving consequence relation defined on the ordered set of values of Smiley’s four-element matrix MSm4. The matrix MSm4 has been of considerable importance in the development of relevant logics and it is at the origin of bilattice logics. It will be shown that Sm4 is a most interesting paraconsistent logic which encloses a sound theory of logical necessity similar to that of Anderson (...) and Belnap’s logic of entailment E. Intuitively, Sm4 can be described as a four-valued expansion of the positive fragment of Lewis’ S5 or, alternatively, as a four-valued version of S5. (shrink)

Hilary Putnam suggests that the essence of the realist conception of mathematics is that the statements of mathematics are objective so that the true ones are objectively true. An argument for mathematical realism, thus conceived, is implicit in Putnam's writing. The first premise is that within currently accepted science there are objective truths. Next is the premise that some of these statements logically imply statements of pure mathematics. The conclusion drawn is that some statements of pure mathematics are objectively true. (...) A key principle assumed is that if one statement logically implies a second, then if the first is objectively true so is the second. A question about this principle is raised and answered. The problem with the argument is with the second premise. (shrink)

This paper is an experiment in Leibnizian analysis. The reader will recall that Leibniz considered all true sentences to be analytically so. The difference, on his account, between necessary and contingent truths is that sentences reporting the former are finitely analytic; those reporting the latter require infinite analysis of which God alone is capable. On such a view at least two competing conceptions of entailment emerge. According to one, a sentence entails another when the set of atomic requirements for (...) the first is included in the corresponding set for the other; according to the other conception, every atomic requirement of the entailed sentence is underwritten by an atomic constituent of the entailing one. The former conception is classical on the twentieth century understanding of the term; the latter is the one we explore here. Now if we restrict ourselves to the formal language of the propositional calculus, every sentence has a finite analysis into its conjunctive normal form. Semantically, then, every sentence of that language can be represented as a simple hypergraph, H, on the powerset of a universe of states. Entailment of the sort we wish to study can be represented as a known relation, subsumption between hypergraphs. Since the lattice of hypergraphs thus ordered is a DeMorgan lattice, the logic of entailment thus understood is the familiar system, FDE of first-degree entailment. We observe that, extensionalized, the relation of subsumption is itself a DeMorgan Lattice ordered by higher-order subsumption. Thus the semantic idiom that hypergraph-theory affords reveals a hierarchy of lattices capable of representing entailments of every finite degree. (shrink)

Sequent calculi for trilattice logics, including those that are determined by the truth entailment, the falsity entailment and their intersection, are given. This partly answers the problems in Shramko-Wansing.

Horwich (Mind 123(491), 2014) has argued that only someone with inflationary tendencies could feel inclined to endorse truth relativism. In doing so, he argues that deflationism about truth entails the denial of relativism. If sound, Horwich’s argument could entail that truth relativism is incompatible with any conception of our ordinary truth predicate according to which there is some sort of equivalence between a ground-language claim that p and the corresponding claim that p is true. Arguably, any (...) story the relativist might give about our ordinary truth predicate, it should entail some such equivalence. Hence, there is a problem for truth relativism that needs to be addressed. Horwich (Mind 123(491), 2014) has argued that only someone with inflationary tendencies could feel inclined to endorse truth relativism. In doing so, he argues that deflationism about truth entails the denial of relativism. If sound, Horwich’s argument could entail that truth relativism is incompatible with any conception of our ordinary truth predicate according to which there is some sort of equivalence between a ground-language claim that p and the corresponding claim that p is true. Arguably, any story the relativist might give about our ordinary truth predicate, it should entail some such equivalence. Hence, there is a problem for truth relativism that needs to be addressed. (shrink)

This book compares John Searle and Michel Foucault's radically opposed views on truth in order to demonstrate the need for invigorating cross-fertilization between the analytic and Continental philosophical traditions. By pressing beyond familiar clichés about analytic philosophy and postmodernism, a surprising convergence of Searle and Foucault's thought on truth emerge. The analytic impression of Foucault is of a radical relativist whose views on truth entail linguistic idealism. Searle himself has contributed to this impression through his aggressive critique (...) of postmodern thinkers, especially Derrida. Prado lays this misperception to rest, showing analytic philosophers that Foucault's ideas about truth are defensible and merit serious attention, while also demonstrating to Continental philosophers that Searle's cannot be ignored. (shrink)

The so-called knowability paradox results from Fitch's argument that if there are any unknown truths, then there are unknowable truths. This threatens recent versions of semantical antirealism, the central thesis of which is that truth is epistemic. When this is taken to mean that all truths are knowable, antirealism is thus committed to the conclusion that no truths are unknown. The correct antirealistic response to the paradox should be to deny that the fundamental thesis of the epistemic nature of (...) truth entails the knowability of all truths. Correctly understood, the antirealistic conditions on a proposition's truth do not require that the proposition possess a verification-procedure which, when executed under the given conditions, issues in an agent's recognition of truth, but merely that there be a verification-procedure which, under these conditions, takes the value true . The knowability paradox and the related idealism problem (that antirealism seems, but is not, committed to the necessary existence of an epistemic agent) draw attention to the fact that certain propositions, those that are about verification-procedures themselves, may under certain conditions take the value true despite their unperformability under these circumstances. Thus these propositions' procedures can only be performed when the propositions are false, and they gain the appearance of antirealistic impossibility (e.g., that there is an unknown truth). This differs from the unperformability that antirealists object to, pertaining merely to matters of execution rather than to the logical structure of the procedures themselves. The force of antirealism's notion of epistemic truth is piecemeal, rather than consisting in a blanket characterization of truth as knowable. (shrink)

In section 1 we argue that the adoption of a tenseless notion of truth entails a realistic view of propositions and provability. This view, in turn, opens the way to the intelligibility of theclassical meaning of the logical constants, and consequently is incompatible with the antirealism of orthodox intuitionism. In section 2 we show how what we call the potential intuitionistic meaning of the logical constants can be defined, on the one hand, by means of the notion of atemporal (...) provability and, on the other, by means of the operator K of epistemic logic. Intuitionistic logic, as reconstructed within this perspective, turns out to be a part of epistemic logic, so that it loses its traditional foundational role, antithetic to that of classical logic. In section 3 we uphold the view that certain consequences of the adoption of atemporal notion of truth, despite their apparent oddity, are quite acceptable from an antirealist point of view. (shrink)

The mainstream view in the philosophy of language holds that every meaningful sentence has a truth-condition. This view, however, runs into difficulties with non-objective sentences such as sentences on matters of taste or value: these do not appear to be either true or false, but are generally taken to be meaningful. How can this conflict be resolved? -/- Truth Without Objectivity examines various ways of resolving this fundamental problem, before developing and defending its own original solution, a relativist (...) theory of truth. Standard solutions maintain either that in uttering non-objective sentences speakers make implicit reference to their own preferences and thus have unproblematic truth conditions, or that they have no truth conditions at all. Max Kölbel argues that both of these proposed solutions are inadequate, and that a third well-known position, minimalism, can only solve the problem if it is developed in the direction of relativism about truth. -/- Kölbel defends the idea that truth (as invoked in semantics) is a neutral notion: a sentence’s possessing a truth condition does not yet entail that it concerns an objective subject matter, because truth and objectivity are independent of one another. He argues that this notion of ‘truth without objectivity’ leads directly to relativism about truth, and goes on to defend one form of relativism against well-known objections. (shrink)