t is often suggested that truth-preservation is insufficient for logical consequence, and that consequence needs to satisfy a further condition of relevance. Premises and conclusion in a valid consequence must be relevant to one another, and truth-preservation is too coarse-grained a notion to guarantee that. Thus logical consequence is the intersection of truth-preservation and relevance. This situation has the absurd consequence that one might concede that the conclusion of an argument was true (since the (...) argument had true premises and was truth-preserving); yet should refuse to infer the conclusion from the premises, in the absence of demonstration of the relevance of the premises to the conclusion. The error lies in giving insufficient attention to the notion of truth-preservation. Relevance is no separable ingredient in the analysis of logical consequence, but a necessary condition of it. What we show is that if an argument really is truth-preserving, then that in itself is enough to show that the premises are (logically) relevant to the conclusion. (shrink)

According to the safety account of knowledge, one knows that p only if one's belief could not easily have been false. An important issue for the account is whether we should only examine the belief in the target proposition when evaluating whether a belief is safe or not. In this paper, it is argued that if we only examine the belief in the target proposition, then the account fails to account for why beliefs in necessary truths could fall short (...) of knowledge. But, if we also examine beliefs in other relevant propositions, then the account fails to preserve epistemic closure. Therefore, the safety account cannot find a safe path between epistemic closure and necessary truths. (shrink)

This paper looks at what David Kaplan's work on indexicals can teach us about logic and the philosophy of logic, and also what Kaplan's logic (i.e. the Logic of Demonstratives) can teach us about indexicals. The lessons are i) that logical consequence is not necessary truth-preservation, ii) that that the linguistic doctrine of necessary truth (also called conventionalism about modality) fails, and iii) that there is a kind of barrier to entailment between non-context-sensitive and context-sensitive (...) claims. (shrink)

It is argued that contraposition is valid for a class of natural language conditionals, if some modifications are allowed to preserve the meaning of the original conditional. In many cases, implicit temporal indices must be considered, making a change in verb tense necessary. A suitable contrapositive for implicative counterfactual conditionals can also usually be found. In some cases, the addition of certain words is necessary to preserve meaning that is present in the original sentence and would be lost (...) or changed in the contrapositive without them. A distinction is made between adding new meaning and adding new words to preserve existing meaning. For concessive conditionals and relevance conditionals, however, no valid contrapositive can be found. They do not belong to the class of contraposable conditionals, which can be independently defined. Difficult cases are also discussed in which the contradictory of the consequent semantically entails the truth of the antecedent. In such cases the content of the antecedent is implicit in the meaning of the consequent. Contraposition becomes possible if what is implicit in the original consequent is made explicit in the contrapositive antecedent. (shrink)

According to a traditional view, logical validity consists in necessary truth preservation. Such an account has been argued to carry an apparent commitment to a unique property of truth to be preserved from premises to conclusion. Recent discussions, however, have concluded that if the metaphor of truth preservation is carefully unpacked, no need for a unique property is there. All is needed is that certain structural relations among instantiations of truth properties hold. Against (...) this view, we argue that a unique general truth property is indeed required by logical validity. We first show that the unpacking should be correctly understood since it imposes constraints on the concept and the properties of truth. We then demonstrate that, under such constraints, a general property is not imposed by truth preservation but by another feature of validity: its uniformity. Finally, some options that could be attempted to resist this result are discussed, showing that (strong) truth pluralism and deflationism are affected in different ways. (shrink)

According to truth pluralism, sentences from different areas of discourse can be true in different ways. This view has been challenged to make sense of logical validity, understood as necessary truth preservation, when inferences involving different areas are considered. To solve this problem, a natural temptation is that of replicating the standard practice in many-valued logic by appealing to the notion of designated values. Such a simple approach, however, is usually considered a non-starter for strong versions (...) of truth pluralism, since designation seems to embody nothing but a notion of generic truth. In this paper, I explore the analogy with many-valued logic by comparing the problem of mixed inferences with Suszko’s thesis, and argue that the strong pluralist has room to resist the commitment to a generic property of truth by undermining the semantic significance of Suszko’s reduction. (shrink)

Monists say that the nature of truth is invariant, whichever sentence you consider; pluralists say that the nature of truth varies between different sets of sentences. The orthodoxy is that logic and logical form favour monism: there must be a single property that is preserved in any valid inference; and any truth-functional complex must be true in the same way as its components. The orthodoxy, I argue, is mistaken. Logic and logical form impose only structural constraints on (...) a metaphysics of truth. Monistic theories are not guaranteed to satisfy these constraints, and there is a pluralistic theory that does so. (shrink)

Alethic pluralism holds that there are many ways of being true. The view has been accused of being unable to do justice to the traditional account of logical validity, understood as necessary truth preservation. In this paper I reformulate the debate in terms of the naturalness of generic truth, and discuss some notable consequences of this more careful reformulation. I show not only that some alleged solutions, like the resort to plural quantification, are ineffective, but also (...) that the problem is not really posed by mixed inferences, as usually thought. Finally, I argue that the traditional account of logical validity does carry a commitment to generic truth, so that a strong version of alethic pluralism can hardly vindicate it. (shrink)

Is truth a supreme value? At times, we doctors have to contend with a complex dilemma in which we face the value of truth on the one hand and conflict with another value on the other. Is it sometimes permissible and even necessary not to report the truth in favour of another, more important value? This is a description of an experience in which a doctor had to handle such an issue when a pregnant Muslim woman (...) asked for a document that she wasn’t pregnant when in fact she was, in order to avert the possibility of being murdered to preserve the honour of the family. The doctor decided that the value of life was more important than the value of truth. (shrink)

Approximation involves representing things in ways that might be close to the truth but are nevertheless false. Given the widespread reliance on approximations in science and everyday life, here we ask whether it is conceptually possible for false approximations to qualify as knowledge. According to the factivity account, it is impossible to know false approximations, because knowledge requires truth. According to the representational adequacy account, it is possible to know false approximations, if they are close enough to the (...) truth for present purposes. In this paper, we adopt an experimental methodology to begin testing these two theories. When an agent provides a false and practically inadequate answer, both theories predict that people will deny knowledge. But the theories disagree about an agent who provides a false but practically adequate answer: the factivity hypothesis again predicts knowledge denial, whereas the representational adequacy hypothesis predicts knowledge attribution. Across two experiments, our principal finding was that people tended to attribute knowledge for false but practically adequate answers, which supports the representational adequacy account. We propose an interpretation of existing findings that preserves a conceptual link between knowledge and truth. According to this proposal, truth is not necessary for knowledge, but it is a feature of prototypical knowledge. (shrink)

The traditional view that all logical truths are metaphysically necessary has come under attack in recent years. The contrary claim is prominent in David Kaplan’s work on demonstratives, and Edward Zalta has argued that logical truths that are not necessary appear in modal languages supplemented only with some device for making reference to the actual world (and thus independently of whether demonstratives like ‘I’, ‘here’, and ‘now’ are present). If this latter claim can be sustained, it strikes close (...) to the heart of the traditional view. I begin this paper by discussing and refuting Zalta’s argument in the context of a language for propositional modal logic with an actuality connective (section 1). This involves showing that his argument in favor of real world validity his preferred explication of logical truth, is fallacious. Next (section 2) I argue for an alternative explication of logical truth called general validity. Since the rule of necessitation preserves general validity, the argument of section 2 provides a reason for affirming the traditional view. Finally (section 3) I show that the intuitive idea behind the discredited notion of real world validity finds legitimate expression in an object language connective for deep necessity. (shrink)

This article discusses Rik Peels's response to Williams's argument against voluntary belief. Williams argues that voluntary beliefs must be acquired independently of truth-considerations, so they cannot count as beliefs after all, since beliefs aim at truth. Peels attempted to reply by showing that in cases of self-fulfilling beliefs, a belief can indeed be voluntarily acquired in conditions which retain the necessary truth-orientation. But even if we make two crucial concessions to Peels’s proposal, his argument ultimately fails. (...) The first concession is that beliefs can be weakly voluntary-namely, we can acquire them at will though we do not preserve them at will but on the basis of evidence. Conceding this, however, only lands us in the “acquisition problem”: how a belief can be acquired qua belief when we still do not think we have justification for it. This leads us to the second concession: that knowing in advance that a certain belief is self-fulfilling provides us with such a justification. However, this concession lands us in the ultimate obstacle: that, precisely because such a justification is available both before and at the moment of forming the belief, the cognitive perspective of the subject is identical at both moments, which obscures what it even means to say that at a certain moment she started to have a belief. (shrink)

John MacFarlane has recently argued that his brand of truth relativism provides the best solution to the puzzle of future contingents: assertions about the future that express propositions that are metaphysically neither necessary nor impossible. In this paper, we show that even if we grant all of the metaphysical, semantic and pragmatic assumptions in terms of which MacFarlane sets and aims to solve the puzzle, his truth relativism is not apt to solve the problem of future contingents. (...) We argue that the theory fails to vindicate the intuition that future contingent propositions are neither true nor false, leaving the theory open to a charge of Reductio. We show that these problems cannot be answered while preserving the core tenets of truth relativism. (shrink)

When in classical formal logic the notions of deduction, valid inference and logical consequence are defined, causal language plays no role. The founder of western logic, Aristotle, identified ‘non-cause’, or ‘positing as cause what is not a cause’, as a logical fallacy. I argue that a systematic re-examination of Aristotle's analysis of NCF, and the related language of logical causality, in the Sophistical Refutations, Topics, Analytics and Rhetoric, helps us to understand his conception of. It reveals that Aristotle's syllogismhood is (...) non-monotonic, and thus narrower than classical validity as consisting in, or coextensive with, necessary truth-preservation. It also supports the conclusion that a syllogism is a form of relevant consequence: the premisses must be causes of the conclusion in the sense that they are not only sufficient but also necessary for the conclusion to follow. Close analysis of NCF also suggests that syllogistic relevance is not a semantic matter, but a syntactic.. (shrink)

Gómez-Torrente’s papers have made important contributions to vindicate Tarski’s model-theoretic account of the logical properties in the face of Etchemendy’s criticisms. However, at some points his vindication depends on interpreting the Tarskian account as purportedly modally deflationary, i.e., as not intended to capture the intuitive modal element in the logical properties, that logical consequence is (epistemic or alethic) necessary truth-preservation. Here it is argued that the views expressed in Tarski’s seminal work do not support this modally deflationary (...) interpretation, even if Tarski himself was sceptical about modalities. (shrink)

Gómez-Torrente’s papers have made important contributions to vindicate Tarski’s model-theoretic account of the logical properties in the face of Etchemendy’s criticisms. However, at some points his vindication depends on interpreting the Tarskian account as purportedly modally deflationary, i.e., as not intended to capture the intuitive modal element in the logical properties, that logical consequence is (epistemic or alethic) necessary truth-preservation. Here it is argued that the views expressed in Tarski’s seminal work do not support this modally deflationary (...) interpretation, even if Tarski himself was sceptical about modalities. (shrink)

There are several three-valued logical systems that form a scattered landscape, even if all reasonable connectives in three-valued logics can be derived from a few of them. Most papers on this subject neglect the issue of the relevance of such logics in relation with the intended meaning of the third truth-value. Here, we focus on the case where the third truth-value means unknown, as suggested by Kleene. Under such an understanding, we show that any truth-qualified formula in (...) a large range of three-valued logics can be translated into KD as a modal formula of depth 1, with modalities in front of literals only, while preserving all tautologies and inference rules of the original three-valued logic. This simple information logic is a two-tiered classical propositional logic with simple semantics in terms of epistemic states understood as subsets of classical interpretations. We study in particular the translations of Kleene, Gödel, ᴌukasiewicz and Nelson logics. We show that Priest’s logic of paradox, closely connected to Kleene’s, can also be translated into our modal setting, simply by exchanging the modalities possible and necessary. Our work enables the precise expressive power of three-valued logics to be laid bare for the purpose of uncertainty management. (shrink)

Alethic pluralism holds that there are many truth properties. The view has been challenged to make sense of the notion of logical validity, understood as necessary truth preservation, when inferences involving different areas of discourse are concerned. I argue that the solution proposed by Edwards to solve the analogous problem of mixed compounds can straightforwardly be adapted to give alethic pluralists also a viable account of validity.

Alethic pluralism holds that there are many ways of being true. Such a view has been challenged to make sense of the standard account of logical validity as necessary truth preservation. In this paper, the recent solution elaborated by Aaron Cotnoir, based on an algebraic approach, is shown to be untenable. Some reflections about the relation of many-valued logics with truth pluralism are also discussed.

Nicolas Malebranche (1638-1715) holds that the senses, imagination, and passions aim at survival and the satisfaction of the body’s needs, rather than truth or the good of the mind. Each of these faculties makes a distinctive and, indeed, an indispensable contribution to the preservation of life. Commentators have largely focused on how the senses keep us alive. By comparison, the imagination and passions have been neglected. In this paper, I reconstruct Malebranche’s account of how the imagination contributes to (...) the preservation of the body by compensating for the limitations of the senses. First, the imagination represents non-actual states of affairs, such as probable or possible future states. Second, the imagination forges new and often helpful associations based on past experiences. Third, the imagination (mis)represents that objects will cause pleasure and pain, thereby imbuing them with emotional significance they would otherwise lack. Together, these features flesh out Malebranche’s view that the imagination is necessary for the preservation of life. (shrink)

In this paper I examine Avicenna’s conception of the consequence relation. I will consider in particular his categorical and hypothetical logics. I will first analyse his definition of the implication and will show that this relation is not a consequence relation in his frame. Unlike the medieval logicians, he does not distinguish explicitly between material and formal consequences. The arguments discussed in al-Qiyās, where the conclusion is true only in some matters, and would seem close to a material consequence for (...) that reason, are rejected explicitly as not syllogistic. He also rejects the ‘enthymemes’ unless they are complemented by their missing premise and the superfluous premises which, according to him, should promptly be ruled out. It seems then that the consequence relation in his theory is formal. It can be characterized as being ‘productivity in all matters’ or ‘necessary truth preserving’. It is illustrated by some single premise arguments, and above all by all kinds of syllogisms which, in his theory, are more numerous and various than in Aristotle’s one. The syllogism may contain two or more premises, including disjunctive ones. When it is hypothetical, it may lead to several conclusions. The premises may be in conflict, but then, the conclusion is false. He thus rejects the principle according to which ‘anything follows from a contradiction’. But, unlike what some scholars say, he does not admit any connexive principle. In the compound syllogisms, the conclusion follows by steps, each step taking two premises at once. (shrink)

Since last year, major initiatives have been undertaken by the chair of theoretical philosophy at the University of Tübingen in order to enhance the reception of analytic metaphysics in the European landscape. Here we review the 2013 summer workshop, intended to be the first of an annual series, on “Existence, Truth and Fundamentality”, the invited speakers being Graham Priest (Melbourne), Stephan Leuenberger (Glasgow), Dan López de Sa (Barcelona), Francesco Berto (Aberdeen), Friederike Moltmann (Paris – Pantheon Sorbonne) and Jason Turner (...) (Leeds). The workshop’s scope is fairly large, focusing on three different aspects of contemporary research in metaphysics. However, the underlying idea of organizers Thomas Sattig and Alessandro Torza consisted in exploring their interconnections and even new areas which possibly share the same problem spectrum. Also, they thought of bringing together both young and senior protagonists of the contemporary debate. In this sense, the main thread followed by the speakers consisted in enquiring the ideas of fundamentality, dependence and grounding with respect to ontology (Berto, López de Sa, Turner) and the truthmaking debate (Priest, Moltmann, Leuenberger), thus pretty much in line with some latest tendencies in metaphysics, such as, prima inter paria, the works of Kit Fine. When we say that something is more fundamental than something else, we move into a non-conventional (for the standards of 20 th century philosophy) metodological framework, hardly focusing on the question about what there is, and rather tackling the issue of how fundamentally there is what there is, or how the existence of something is required as a ground for the existence of other things. Here is how Jonathan Schaffer explains the methodological transition in his influential “On What Grounds What” (2009): -/- Among the many assumptions Quine and Carnap share is that metaphysical questions are existence questions, such as whether numbers exist. They only disagree on the further issue of whether such questions are meaningful (at least as the metaphysician might pose them). But why think that metaphysical questions are existence question of this sort? Return to Aristotle’s Metaphysics. There are virtually no existence question posed. The whole discussion is about substances (fundamental units of being). At one point Aristotle pauses to ask if numbers exist, and his answer is a brief and dismissive yes. [. . . ] For Aristotle, the question about numbers is whether they are transcendent substances or grounded in concreta. The question is not whether numbers exist, but how. (Schaffer, 2009, p. 347) -/- The conference opened with Graham Priest’s intriguing and peculiar review of Buddhist cornerstone “The Fundamental Verses of the Middle Way” (Mūlamadhyakamakārikā) by Nāgārjuna (ca. 150-ca. 250 AD), seen as a unrecognized forerunner of multi-valued semantics and dialetheism. Priest shows that Nagarjuna’s thought indeed has valuable analytic grip (contrary to the traditional mystical dismiss of his works altogether) and is even in accord to some formal schemas rejecting both the laws of excluded middle and non-contradiction. Dan López de Sa was interested in the topic of grounding, raising concerns about how to explain the kind of “reality” exemplified by what is not fundamental, but rather derivative on something else. He proposes a conceptual and non-primitive analysis of grounding as linked to fundamentality and derivation, and argues that the view can be advocated along with the acceptance that at least something is not fundamental. Subsequently, he illustrates an impressive range of applications linked to contemporary debates in meta-ontology, truthmaking and philosophy of time. Stephan Leuenberger discussed a semantics for “total logic”, a variant of first order logic which is claimed to have several applications with respect to the issue of excluding negative existentials from the scope of theories accounting for a given ’totality’ of facts. For example, materialism is the claim that everything there is can be traced back to physical facts or to truth implied by those facts. What about the claim that “There are no angels”? According to Leuenberger, ordinary logic falls prey of modal arguments (if it is possible that there are angels, by modus tollens, that it is not metaphysically necessary that everything there is is physical). So, there is space for the introduction of a new operator, the totality operator, claiming of what enters its scope that “that’s the whole truth”. Consequently, total logic’s semantics tackles David Chalmers’ well-known conceivability-based argument in favour of zombie’s (subjects producing behaviour but experiencing no qualia) possible existence. Friederike Moltmann presented a massive array of natural language-based examples on the role played by case-constructions, such as “it is the case that Caesar crossed the Rubicon”, “the case of the stolen statue”, “the case in which it might rain”, and so forth. She suggests that we should take surface phenomena of our language very seriously with regard to the determination of ontological categories and truth-makers. Cases are provided by many natural languages with their own existence predicates (“to occur” and “to present itself ”), and these do not apply to other kind of entities, such as objects and events. Trying to derive a substantive thesis on their nature, she claims that they are filtered entities, a structure taking into account some features of the corresponding objects and events and preserving their relational pattern. Jason Turner discussed meta-ontological concerns against the claim that ontological debates are defective. Analysed the structure of a metaphysical theory and identified two different forms of defectiveness that can occur in ontological questions, the defection from without and the defection from within, the author provided an original solution in order to avoid such difficulties. He argued thus in favor of a logical constancy, a translation principle thanks to it would be possible reconceive an ontological defection. Lastly, Francesco Berto’s talk closed the workshop with a sagacious discussion of meinongian quantification. He substains that Meinongians and Quineans experience no conceptual equivocation. Even if the former claims that “There are things that do not exist”, something that the latter contrasts with the interpretation of existential quantifiers as all-including, they still rely upon the same concept of “existence” and they understand each other when they are outside the ontology room, so that it cannot be that they lack competence. Subsequently, Berto deals with the objection that Meinongians commit analytic falsehood in separating the meaning of “to be” from that of “exists”. The Quinean has no independent evidence for analytic equivalence aside from her emphatic stress on the “is” in “there is”. Meinongians, however, can retort to linguistic considerations and claim that existence predicates display fairly different functions. -/- As for what regards our internal division of the “philosophical labor”, Fabio Ceravolo reviewed Moltmann and Berto’s talks; whereas Mattia Cozzi took care of Priest’s and Leuenberger’s, and Mattia Sorgon of those given by López de Sa and Turner. Conclusively, we would like to thank Thomas Sattig and Alessandro Torza for all of their organizational efforts and the kind welcome they reserved to us. We hope we will have further opportunities to collaborate with Tübingen in supporting similarly innovative and valiant european initiatives. (shrink)

This paper examines the interaction between the philosophy and psychology of concepts and the modal characterization of the deductive concept of logical validity. The concept of logical consequence on which I focus is model-theoretic, where the concept records the property of necessary truth-preservation from the premise of an argument to its conclusion, as well as the condition that, in the class of all possible worlds in which a premise is true, a consequent formula or succedent class of (...) formulas is true, as well. Focusing on the case of logical necessity, I argue that the ability to account for the modal properties of concepts places a desideratum on the explanatory adequacy of theories of mental representation. I outline, then, five approaches to the nature of concepts pursued in philosophy and cognitive science, and argue that the above desideratum does not appear to be satisfiable by the candidate proposals. Given the limits of the foregoing, I appeal to a sixth approach -- namely, cognitivism about epistemic modality, according to which epistemic intensions are semantically imbued functions in the language of thought -- and endeavor to demonstrate how the proposal can sufficiently account for the modal profile of the concept of logical consequence. (shrink)

J.C. Beall and Greg Restall's Generalised Tarski Thesis is a generalisation of the seemingly diverse conceptions of logical consequence. However, even their apparently general account of consequence makes necessary truth-preservation a necessary condition. Sentences in the imperative mood pose a problem for any truth-preservationist account of consequence, because imperatives are not truth-apt but seem to be capable of standing in the relation of logical consequence. In this paper, I show that an imperative logic can (...) be formulated that solves the problem of imperative consequence by leading naturally to a further generalisation of the GTT. (shrink)

This article aims to shed light on the so-called post-truth moment and the responses of Walter Lippmann, Carl Schmitt, and John Dewey to the unstable basis and implications of truth—empirical or scientific, moral and axiological—in politics. At stake historically and today is an attempt to find political authority grounded in truth so as to preserve an autonomous sphere of freedom for the individual against the potentially irrational subjectivism backed by coercive force. Lippmann and Schmitt mirror the contemporary (...) distrust (or insistence as inescapable fact) of subjectivism and the rejection of pluralism as offering truth as an ordering principle for politics. I argue that Dewey’s turn to inquiry and his conception of truth and politics provides a timely defense of participatory democracy and a democratic ethos necessary to commit to acting on verifiable truth claims. I conclude by applying Dewey’s insights to current scholarship on truth, inquiry, and polarization today. (shrink)

This article aims to shed light on the so-called post-truth moment and the responses of Walter Lippmann, Carl Schmitt, and John Dewey to the unstable basis and implications of truth—empirical or scientific, moral and axiological—in politics. At stake historically and today is an attempt to find political authority grounded in truth so as to preserve an autonomous sphere of freedom for the individual against the potentially irrational subjectivism backed by coercive force. Lippmann and Schmitt mirror the contemporary (...) distrust (or insistence as inescapable fact) of subjectivism and the rejection of pluralism as offering truth as an ordering principle for politics. I argue that Dewey’s turn to inquiry and his conception of truth and politics provides a timely defense of participatory democracy and a democratic ethos necessary to commit to acting on verifiable truth claims. I conclude by applying Dewey’s insights to current scholarship on truth, inquiry, and polarization today. (shrink)

Leibniz sought to solve the metaphysical problem of reality, avoiding ontological premises. His intensional method was aimed at the logical solution of the problem, preserving the objectivity and unobstructed metaphysical research. Metaphysics can provide a certain level of coherence to the phenomena of physics and make them more real. Leibniz was convinced that physics, for its part, should be grounded in metaphysical principles. This promotes a reciprocal relationship between physics and metaphysics, where metaphysical principles derive their reality from physical principles, (...) and the two fields are interrelated. If we recognize the reality of the laws of physics, then we must also recognize the reality of the concept of substance. His position is that the laws of mathematical physics predict the existence of real substances, which makes it possible to move from mathematical objects to real substances. This method of substantiating the reality of substance and metaphysical principles can be considered as the foundations of the transcendental method. Leibniz's metaphysical approach is that necessary truths exist by themselves and do not depend on specific objects of study or perception. He regarded these truths as eternal. (shrink)

Some arguments include imperative clauses. For example: ‘Buy me a drink; you can’t buy me that drink unless you go to the bar; so, go to the bar!’ How should we build a logic that predicts which of these arguments are good? Because imperatives aren’t truth apt and so don’t stand in relations of truth preservation, this technical question gives rise to a foundational one: What would be the subject matter of this logic? I argue that declaratives (...) are used to produce beliefs, imperatives are used to produce intentions, and beliefs and intentions are subject to rational requirements. An argument will strike us as valid when anyone whose mental state satisfies the premises is rationally required to satisfy the conclusion. For example, the above argument reflects the principle that it is irrational not to intend what one takes to be the necessary means to one’s intended ends. I argue that all intuitively good patterns of imperative inference can be explained using off-the-shelf formulations of our rational requirements. I then develop a formal-semantic theory embodying this view that predicts a range of data, including free-choice effects and Ross’s paradox. The resulting theory shows one way that our aspirations to rational agency can be discerned in the patterns of our speech, and is a case study in how the philosophy of language and the philosophy of action can be mutually illuminating. (shrink)

A truth-preservation fallacy is using the concept of truth-preservation where some other concept is needed. For example, in certain contexts saying that consequences can be deduced from premises using truth-preserving deduction rules is a fallacy if it suggests that all truth-preserving rules are consequence-preserving. The arithmetic additive-associativity rule that yields 6 = (3 + (2 + 1)) from 6 = ((3 + 2) + 1) is truth-preserving but not consequence-preserving. As noted in James (...) Gasser’s dissertation, Leibniz has been criticized for using that rule in attempting to show that arithmetic equations are consequences of definitions. -/- A system of deductions is truth-preserving if each of its deductions having true premises has a true conclusion—and consequence-preserving if, for any given set of sentences, each deduction having premises that are consequences of that set has a conclusion that is a consequence of that set. Consequence-preserving amounts to: in each of its deductions the conclusion is a consequence of the premises. The same definitions apply to deduction rules considered as systems of deductions. Every consequence-preserving system is truth-preserving. It is not as well-known that the converse fails: not every truth-preserving system is consequence-preserving. Likewise for rules: not every truth-preserving rule is consequence-preserving. There are many famous examples. In ordinary first-order Peano-Arithmetic, the induction rule yields the conclusion ‘every number x is such that: x is zero or x is a successor’—which is not a consequence of the null set—from two tautological premises, which are consequences of the null set, of course. The arithmetic induction rule is truth-preserving but not consequence-preserving. Truth-preserving rules that are not consequence-preserving are non-logical or extra-logical rules. Such rules are unacceptable to persons espousing traditional truth-and-consequence conceptions of demonstration: a demonstration shows its conclusion is true by showing that its conclusion is a consequence of premises already known to be true. The 1965 Preface in Benson Mates (1972, vii) contains the first occurrence of truth-preservation fallacies in the book. (shrink)

Contemporary philosophy standardly accepts Frege's conceptions of sense as the determiner of reference and of analyticity as (necessary) truth in virtue of meaning. This paper argues that those conceptions are mistaken. It develops referentially autonomous notions of sense and analyticity and applies them to the semantics of natural kind terms. The arguments of Donnellan, Putnam, and Kripke concerning natural kind terms are widely taken to refute internalist and rationalist theories of meaning. This paper shows that the counter-intuitive consequences (...) about the reference of natural kind terms depend as much on Frege's conceptions of sense and analyticity as on what such theories of meaning say about the senses of natural kind terms. Rather than refuting the internalist and rationalist theories of meaning, the arguments of Donnellan, Putnam, and Kripke are best recast as refutations of their own Fregean assumptions. The paper also shows how autonomous notions of sense and analyticity enable us to reconstruct such theories, formulate an internalist/ rationalist account of semantic knowledge, and preserve Donnellan's, Putnam's, and Kripke's insights about reference. (shrink)

Contemporary philosophy standardly accepts Frege’s conceptions of sense as the determiner of reference and of analyticity as (necessary) truth in virtue of meaning. This paper argues that those conceptions are mistaken. It develops referentially autonomous notions of sense and analyticity and applies them to the semantics of natural kind terms. The arguments of Donnellan, Putnam, and Kripke concerning natural kind terms are widely taken to refute internalist and rationalist theories of meaning. This paper shows that the counter-intuitive consequences (...) about the reference of natural kind tenns depend as much on Frege’s conceptions of sense and analyticity as on what such theories of meaning say about the senses of natural kind tenns. Rather than refuting the internalist and rationalist theories of meaning, the arguments of Donnellan, Putnam, and Kripke are best recast as refutations of their own Fregean assumptions. The paper also shows how autonomous notions of sense and analyticity enable us to reconstruct such theories, formulate an internalist/rationalist account of semantic knowledge, and preserve Donnellan’s, Putnam’s, and Kripke’s insights about reference. (shrink)

Philosophical analysis of mathematical knowledge are commonly conducted within the realist/antirealist dichotomy. Nevertheless, philosophers working within this dichotomy pay little attention to the way in which mathematics evolves and structures itself. Focusing on mathematical practice, I propose a weak notion of objectivity of mathematical knowledge that preserves the intersubjective character of mathematical knowledge but does not bear on a view of mathematics as a body of mind-independent necessary truths. Furthermore, I show how that the successful application of mathematics in (...) science is an important trigger for the objectivity of mathematical knowledge. (shrink)

Are rights to privacy consistent with sexual equality? In a brief, but influential, article Catherine MacKinnon trenchantly laid out feminist criticisms of the right to privacy. In “Privacy v. Equality: Beyond Roe v. Wade” she linked familiar objections to the right to privacy and connected them to the fate of abortion rights in the U.S.A. (MacKinnon, 1983, 93-102). For many feminists, the Supreme Court’s decision in Roe v. Wade (1973) had suggested that, notwithstanding a dubious past, legal rights to privacy (...) might serve feminist objectives, and prove consistent with sexual equality. By arguing that Roe’s privacy justification of abortion rights was directly responsible for the weakness and vulnerability of abortion rights in America, MacKinnon took aim at feminist hopes for the right to privacy at their strongest point. Maintaining that Roe’s privacy justification of abortion is intimately, and not contingently, related to the Supreme Court’s subsequent decision in Harris v. McRae, (1980) MacKinnon concluded that privacy rights cannot be reconciled with the freedom and equality of women, and so can have no place in a democracy.1 In Harris, the Supreme Court held that the State need not provide Medicaid coverage for abortions that are necessary to preserve the health, but not the life, of a pregnant woman, effectively depriving poor women of almost all state aid for abortions.2 Moreover, the Court’s subsequent decision in Bowers v . Hardwick (1986) appeared to confirm the truth of MacKinnon’s observation – though this case concerned gay rights, rather than abortion rights, and occurred several years after MacKinnon’s condemnation of Harris. -/- This paper examines MacKinnon’s claims about the relationship of rights to privacy and equality in light of the reasoning in Harris and Bowers. When we contrast the Majority and Minority decisions in these cases, it shows, we can distinguish interpretations of the right to privacy that are consistent with sexual equality from those that are not. This is not simply because the two differ in their consequences – though they do - but because the former, unlike the latter, rely on empirical and normative assumptions that would justify sexual inequality whatever right they were used to interpret. So while I agree with MacKinnon that the Majority’s interpretation of the right to privacy in Harris is inconsistent with the equality of men and women, I show that there is no inherent inconsistency in valuing both privacy and equality, and no reason why we must chose to protect the one, rather than the other. Indeed, an examination of MacKinnon’s article, I suggest, can help us to see why rights to privacy can be part of a scheme of democratic rights, and how we might go about democratising the right to privacy in future. To avoid confusion I should emphasise that my arguments are of a philosophical, not a legal, nature. Thus, I will be ignoring the specifically legal and constitutional aspects of MacKinnon’s article, and of the Supreme Court decisions, in order to bring their philosophical significance into focus. -/- . (shrink)

Essentialist legal theorists, represented by Raz, have depicted legal theory as a project of seeking necessary truths about law. They have, however, left the notion of necessity in their conception of legal theory largely unexplained. This paper explores four different notions of necessity in the philosophical literature and investigates two issues: first, what kind of necessity best fits the notion of necessity implicit in the essentialist conception of legal theory, and secondly, whether that notion of necessity is a coherent (...) one that withstands philosophical challenges. I argue that the Putnamian notion of quasi-necessity best fits essentialist legal theorists’ self-understanding, but the notion of quasi-necessity does not withstand Ebbs’s two challenges. Meanwhile, although Plunkett’s theory of metalinguistic negotiation can be used to preserve a coherent notion of necessity that circumvents Ebbs’s two challenges, due to its broadly anti-essentialist underpinnings such a notion is unlikely to be congenial to essentialist legal theorists. (shrink)

Alfred R. Mele defends a broadly 'Humean' theory of motivation. One common dispute between Humeans and anti-Humeans has to do with whether or not a desire is required to motivate action. For the most part Mele avoids this dispute. He claims that there are reasons to think that beliefs cannot motivate action, but finally allows that it might be that it is a contingent fact that beliefs can motivate action in human beings. Instead Mele argues for the claim that certain (...) kinds of desires - namely action-desires - are 'paradigmatic motivational attitudes', similar in an essential way to intentions, and that beliefs are not. Hence it is a necessary truth that action-desires encompass motivation to act; if beliefs encompass motivation to act, it is not a necessary truth that they do. In this way Mele preserves some of what is intuitively right about the Humean account, while admitting that the arguments normally offered in support of the standard Humean claims are open to objections. I argue that Mele's account is implausible. His argument against the claim that state-desires are essentially motivation-encompassing attitudes is convincing, but the same argument proves that action-desires are not essentially motivation-encompassing either. If this difference between desires and beliefs cannot be maintained, however, then Mele fails to defend any motivationally relevant difference between beliefs and desires. (shrink)

'Public reason' in Rawls's stipulated usage signifies propositions that can legitimately be used in deliberating on and deciding fundamental issues of political life and legislation because they are propositions which all citizens may reasonably be expected to endorse: their use is therefore fair (respects the moral principle of reciprocity) and preserves the public peace which is at risk from contests between comprehensive doctrines, contests exemplified by wars of religion. This attractive set of suggestions is ruined by irresoluable ambiguities, truncation of (...) reason's resources and of public discourse just when they are most needed, and incipient capitulation to some radical injustices. But public reason may nonetheless be an opportune phrase for conveying the gist of four permanently valid theses in the classical political thought that develops from Socrates/Plato to Aquinas and beyond. That tradition has been significantly modified by recognition that a human right to immunity of religious beliefs and acts from coercion extends – precisely by reason of the importance of finding and adhering to the truth about the divine source of reality and value – to mistaken as well as correct religious beliefs and practices. That immunity is subject to limitations necessary to preserve public order; likewise, a religion's legitimacy as a source of reasons for public actions is dependent on its willingness to foster genuine public discourse. Analogously, a political or legal philosophy's rational warrant is dependent on the compatibility of its theses with the worth of authentic discourse and the support they give to institutions, including the rule of law, which favour such discourse. Habermas's account of discourse ethics fails by overlooking some truths about discourse, truth and friendship that Plato made clear in Gorgias. And (the rule of) law, too, is most adequately understood as a product and articulation of public reason. (shrink)

The revisionary approach to semantic paradox is commonly thought to have a somewhat uncomfortable corollary, viz. that, on pain of triviality, we cannot affirm that all valid arguments preserve truth (Beall2007, Beall2009, Field2008, Field2009). We show that the standard arguments for this conclusion all break down once (i) the structural rule of contraction is restricted and (ii) how the premises can be aggregated---so that they can be said to jointly entail a given conclusion---is appropriately understood. In addition, we briefly (...) rehearse some reasons for restricting structural contraction. (shrink)

Resolution of Frege's Puzzle by denying that synonym substitution in logical truths preserves sentence sense and explaining how logical form has semantic import. Intensional context substitutions needn't preserve truth, because intercepting doesn't preserve sentence meaning. Intercepting is nonuniformly substituting a pivotal term in syntactically secured truth. Logical sentences and their synonym interceptions share factual content. Semantic content is factual content in synthetic predications, but not logical sentences and interceptions. Putnam's Postulate entails interception nonsynonymy. Syntax and vocabulary explain only (...) the factual content of synthetic predications; extrasentential reality explains their truth. Construction of logical factual content explains logical necessity. Terms retain objectual reference, but logical syntax preempts their function in explaining truth. Grasping the facts GG/gg assert entails understanding this. Understanding what GH states requires some recognition that GH must be true just because GmH, and GmH state an empirical fact. GH is standardly used to express that fact. Church's Test exposes puzzles. QMi sentences, and QTi sentences are metalogical necessities, true by syntax. Intercepting QMi creates empirical QM contingencies. Synonymy turns semantic contingencies into metalogical and lexical necessities. That transformation is syntactic, via the syntactic duality of definite descriptions. GmH is a contingent copredication, and a lexically necessary referential identity with rigidly codesignating indexicals. Metalogical sentences may be about expressional matter or what it expresses. GG has GG's semantic content, but the referent expression switches. Metalogical syntax secures truth by self-referential quotational indexing. Metalogically, referents are identified with intrasentential replica. Extrasentential identifications are metalogically irrelevant. (shrink)

Analyticity is a bogus explanatory concept, and is so even granting genuine synonomy. Definitions can't explain the truth of a statement, let alone its necessity and/or our a priori knowledge of it. The illusion of an explanation is revealed by exposing diverse confusions: e.g., between nominal, conceptual and real definitions, and correspondingly between notational, conceptual, and objectual readings of alleged analytic truths, and between speaking a language and operating a calculus. The putative explananda of analyticity are (alleged) truths about (...) essential properties. Real definitions (a la Socrates) are the (alleged) explananda, not the explanans of analyticity. Their truth can be explained neither by conceptual definitions (a la Kant), nor by nominal definitions (a la Frege). The Quinean assault on synonomy is unsuccessful and in any case misplaced, because analyticity turns on the explanatory import of synonomy, not its existence. Synonym substitution in a logical truth cannot yield a necessary truth for it doesn't preserve logical form. Self-identity statements (for properties and/or individuals) differ in logical form from alter-identity statements. (shrink)

Résumé — Toute vérité est-elle connaissable en principe ? Une réponse négative à cette question suit d’un argument logique dû à F. Fitch, voisin du paradoxe de Moore, et connu sous le nom de paradoxe de la connaissabilité. Le paradoxe de Fitch constitue un obstacle à la conception antiréaliste de la vérité et, plus généralement, semble-t-il, à l’idéal positiviste d’après lequel toute vérité devrait nous être accessible en principe. Dans cet article, j’examine différentes tentatives pour préserver le principe selon lequel (...) toute vérité est connaissable, chacune inspirée d’une forme propre d’antiréalisme . Ces différentes approches sont comparées à une conception réaliste du positivisme, évoquée récemment par Burgess, qui postulerait seulement que toute vérité nécessaire est connaissable. Selon cette conception, certaines vérités contingentes sont effectivement inconnaissables, mais l’accessibilité de principe des vérités nécessaires demeure suffisante pour garantir la confiance positiviste dans la science.— Are all truths knowable ? A negative answer to this question follows from a logical argument related to the Moore Paradox and due to F. Fitch, also known as Fitch’s Knowability Paradox. Fitch’s paradox is widely considered to be an obstacle to the antirealist conception of truth, but even for a realist, it appears to threaten the positivist faith in the accessibility of all truths to our minds. In this paper, I first review different strategies to circumvent the paradox, each of them inspired by a different form of antirealism . I then compare these approaches to a realist version of positivism, discussed recently by Burgess, which would only postulate that all necessary truths are knowable. On that view, some contingent truths are indeed unknowable, but the idea that all necessary truths are within our reach remains sufficient to maintain the positivist faith in scientific knowledge. (shrink)

What is informal logic, is it ``logic" at all? Main contemporary approaches are briefly presented and critically commented. If the notion of consequence is at the heart of logic, does it make sense to speak about ``informal" consequence? A valid inference is truth preserving, if the premises are true, so is the conclusion. According to Prawitz two further conditions must also be satisfied in the case of classical logical consequence: (i) it is because of the logical form of the (...) sentences involved and not because of their specific content that the inference is truth preserving; (ii) it is necessary that if the premises are true, then so is the conclusion. According to the prevalent criteria of informal logic an argument is cogent if and only if (i) its premises are rationally Acceptable, (ii) its premises are Relevant to its conclusion and (iii) its premises constitute Grounds adequate for accepting the conclusion (the ``ARG" conditions according to Govier). The ARG criteria characterize a certain broad kind of consequence relation. We do not (in general) have truth preservence in cogent arguments but if the premises are acceptable and other criteria are met, then so is the conclusion. We can speak about form in a loose sense and finally, there is rational necessity of the grounding or support relation. So a certain broad notion of logical consequence emerges from this comparison. The norms of ARG are norms of elementary scientific methodology in which argument is seen as embodying reasoning within a process of inquiry or of belief formation in subject areas accessible to every informed intellectual. (shrink)

Many arguments are affected by context sensitivity, because they include sentences that have different truth conditions in different contexts. Therefore, it is natural to think that a general criterion for evaluating arguments must take context sensitivity into account. One way to give substance to that thought is provided by the definition of validity offered by David Kaplan within his theory of indexicals. However, the route indicated by Kaplan is hindered by a problem whose importance is often underestimated. This paper (...) explores a different route, and outlines a definition of validity that does not run into that problem. Its moral is that Kaplan's definition is not the only plausible definition. This is not to say that the definition outlined is the only plausible definition or that it is correct in some absolute sense. There might be equally important problems with it that the paper does not take into account. But until such problems are found and brought up, the departure from Kaplan's route remains a viable option. (shrink)

According to the knowledge view of evidence notoriously defended by Timothy Williamson (2000), for any subject, her evidence consists of all and only her propositional knowledge (E=K). Many have found (E=K) implausible. However, few have offered arguments against Williamson’s positive case for (E=K). In this paper, I propose an argument against Williamson’s positive case in favour of (E=K). Central to my argument is the possibility of the knowledge of necessary truths. I also draw some more general conclusions concerning theorizing (...) about evidence. (shrink)

Abstract For all of its blessings, democracy in America displays weaknesses. Democratic theorists both disguise and exacerbate these weaknesses by urging us, as imperatives of democratic justice, to extend the claims of equality to all practices and throughout all spheres of life; and to discount what people actually want in favor of what democratic theorists think that reason tells us people ought to want. Such theorizing encourages the evisceration of virtue, the trivialization of truth, the subjugation of chance, the (...) fear of freedom, and the routinization of romantic love. To combat the dogmatism and despotism to which democracy is prone, it is necessary to preserve the distinction between democracy and justice. (shrink)

In Saving Truth from Paradox, Hartry Field presents and defends a theory of truth with a new conditional. In this paper, I present two criticisms of this theory, one concerning its assessments of validity and one concerning its treatment of truth-preservation claims. One way of adjusting the theory adequately responds to the truth-preservation criticism, at the cost of making the validity criticism worse. I show that in a restricted setting, Field has a way to (...) respond to the validity criticism. I close with some general considerations on the use of revision-theoretic methods in theories of truth. (shrink)

Les conditions dans lesquelles Leibniz a été amené à recourir au néologisme de « dynamique » permettent de mettre en évidence la nouveauté, au regard des élaborations antérieures fondées sur la notion de force, des dispositifs conceptuels résultant de la conservation de l'action motrice. La démonstration a priori de la conservation de l'action n'a nullement pour effet de transformer la dynamique en science mathématique des vérités nécessaires, ni d'oblitérer sa dépendance à l'égard des principes métaphysiques. La singularité stylistique du concept (...) d'action s'exprime dans sa constitution duale, associant quantité extensive et quantité intensive : par là, la dynamique leibnizienne renouait avec les doctrines médiévales de l'intensio; attribuant en outre aux corps une véritable « action sur soi », corrélativement à une conception archaïque de l'inertie, elle était originellement incommensurable au paradigme de la mécanique classique. The circumstances which led Leibniz to resort to the neologism of "Dynamics" highlight the novelty of the conceptual systems — compared to the previous conceptions based on the notion of force — resulting from interference of motive action. The a priori demonstration of the preservation of action does not transform dynamics into a mathematical science of necessary truths nor does it obliterate its dependance on metaphysical principles. The stylistic singularity of the concept of action becomes apparent in its dual constitution which associates extensive quantity and intensive quantity: thus Leibniz's dynamics revived the medieval doctrines of intensio; moreover as it endowed bodies with a true "action on themselves", in correlation with archaic understanding of inertia, it was originally irreducible to the paradigm of classical mechanics. (shrink)

Conceptual analysis of logical consequence can be regarded as a crucial part of any logical theory. The present paper focuses on John Mair’s approach to this issue from both historical and systematic point of view. Mair’s task is to analyse the concepts of modality and validity in universal token-based languages with non-compositional semantics based on network evaluation. To fulfil it, Mair addresses modal paradoxes, validity paradoxes and inferences with paradoxical components. Both truth and modality and truth and validity, (...) when conceived as semantic properties, turn out to be mutually independent as a result of Mair’s semantics: there are true impossible propositions and possible propositions which cannot be true and truth-preservation turns out to be neither a sufficient nor a necessary condition for validity. (shrink)

In this essay, I argue that Hume’s theory of Quantitative and Numerical Philosophical Relations can be interpreted in a way which allows mathematical knowledge to be about a body of objective and necessary truths, while preserving Hume’s nominalism and the basic principles of his theory of ideas. Attempts are made to clear up a number of obscure points about Hume’s claims concerning the abstract sciences of Arithmetic and Algebra by means of re-examining what he says and what he could (...) comfortably have said about relations of qualitative resemblance. (shrink)

According to a standard story, part of what we have in mind when we say that an argument is valid is that it is necessarily truth preserving: if the premises are true, the conclusion must also be true. But—the story continues—that’s not enough, since ‘Roses are red, therefore roses are coloured’ for example, while it may be necessarily truth-preserving, is not so in virtue of form. Thus we arrive at a standard contemporary characterisation of validity: an argument is (...) valid when it is NTP in virtue of form. Here I argue that we can and should drop the N; the resulting account is simpler, less problematic, and performs just as well with examples. (shrink)