El presente escrito discute la plausibilidad de la admisión de términos generales rígidos no naturales. Enunciados de identidad teórica que incluyen términos generales rígidos no naturales no expresan necesidad a posteriori: son enunciados analíticos, necesarios y a priori. Sólo los enunciados de identidad que incluyen términos generales rígidos naturales son enunciados necesarios a posteriori. Los problemas de la trivialización y sobre generalización suponen que la aplicación de la rigidez a los términos de clase no natural resta importancia (...) a la rigidez como diferenciador semántico – modal, pero eso solo es así si estos problemas exigen que cualquier término general rígido permita afirmar necesidad a posteriori, lo que es rechazado. Se propone la nominalización de un término general como una vía de solución a la trivialización y la sobregeneralización. Del mismo modo, se descarta una lectura predicativa restrictiva de los términos generales. Finalmente, se explicita el principal caso de términos generales no rígidos: términos descriptivos sintácticamente complejos. (shrink)

Se afirma que los enunciados necesarios a posteriori, propuestos por S. Kripke, exigen una comprensión débil de la necesidad; esto quiere decir: a) existencia contingen-te del designatum(no existencia en toda situación contrafáctica) y b) dependencia racionalista en principios lógicos a priori, particularmente los de diferencia y de identidad. La principal consecuencia es que los enunciados necesarios a posteriori corresponden a instancias de dichos principios lógicos. Contrario al racionalismo, esto no exige que dichos enunciados sean a priori, pues (...) su justificación requiere in-formación empírica. Finalmente, se defiende que la distinción entre denotación y designación permite sostener que la necesidad débil se aplica a las instanciasde la clase, y no a esta, con lo que se evita el indeterminismo referencial. (shrink)

Resumen: El presente escrito argumenta cómo el denominado abuso de lo necesario a posteriori, propuesto en Beebee y Sabbarton-Leary, asume erróneamente que: a) los enunciados necesarios a posteriori requieren un compromiso metafísico con un esencialismo no trivial; y b) que el experimento mental de la tierra gemela cumple un rol evidencial en la determinación de lo necesario a posteriori. Contra a), se sostiene que lo necesario a posteriori no requiere un compromiso esencialista no trivial; a lo (...) sumo, el esencialismo no trivial es consecuencia de la propuesta de lo necesario a posteriori. Contra b), se afirma cómo el experimento mental de la tierra gemela cumple un rol subsidiario, explicativo y no evidencial. Esto evita un compromiso ontológico con el nexo concebible - posible. Luego, se discute cómo la noción de co- referencialidad rígida es una vía de solución a la exigencia de esencialismo no trivial. Finalmente, se considera de qué modo el esencialismo científico de Brian Ellis, al enunciar condiciones a priori de satisfacción, no afecta la justificación de lo necesario a posteriori. Del mismo modo, se defiende un nexo término rígido de jure/clase sustancial - término rígido de facto/clase propiedad.: This paper discusses how the so-called "abuse of the necessary a posteriori", proposed by Beebee and Sabbarton-Leary, erroneously assumes that: a) necessary a posteriori statements require a metaphysical commitment to a non-trivial essentialism, and b) the thought experiment of the twin earth fulfills an evidential role in determining the necessary a posteriori. Against a), it is argued that the necessary a posteriori does not require a non-trivial essentialist commitment; at most, nontrivial essentialism is a consequence of the necessary a posteriori. Contra b), it is stated how the thought experiment of the twin earth fulfills a subsidiary, explanatory, and non-evidential role. This prevents an ontological commitment to the conceivable-possible connection. It is then discussed how the notion of rigid coreferentiality is a way of solving the non-trivial essentialism requirement. Finally, we consider how Brian Ellis' scientific essentialism, in stating a priori conditions of satisfaction, does not affect the necessary a posteriori justification. (shrink)

En el presente escrito, los autores pretenden una nueva interpretación de las principales tesis de la más conocida obra de Kripke, Naming and Necessity. Se atiende a las nociones de a priori (y de necesidad) y a posteriori (y contingencia), la noción de designador rígido (con su explícita crítica a la teoría descriptivista fregeana de los nombres) y su revisión de los conceptos metafísicos de modalidad de dicto y modalidad de re. Más tarde, se definirá mínimamente la noción (...) de realismo y se intentará situar a Kripke en el tipo que más cómodamente se adapte a sus presupuestos teóricos de carácter ordinario. Todo ello permitirá situar la teoría kripkeana de los nombres dentro de un marco realista que posibilitará, en otro momento ulterior, formular ciertas críticas a esta Teoría Causal de la Referencia y al realismo metafísico a ella asociada. (shrink)

A posteriori physicalism is the combination of two appealing views: physicalism (i.e. the view that all facts are either physical or entailed by the physical), and conceptual dualism (i.e. the view that phenomenal truths are not entailed a priori by physical truths). Recently, some philosophers such as Goff (2011), Levine (2007) and Nida-Rümelin (2007), among others, have suggested that a posteriori physicalism cannot explain how phenomenal concepts can reveal the nature of phenomenal properties. In this paper, I wish (...) to defend a posteriori physicalism from this new and interesting challenge, by arguing that a posteriori physicalists have the resources to explain how phenomenal concepts can reveal at least something of what it would take for the corresponding phenomenal property to be instantiated. (shrink)

En este trabajo se analizan las nociones de esencia en Husserl y Kripke marcando sus relaciones y diferencias. Husserl excluye una definición modal de la esencia, considerando que las necesidades incondicionadas tienen su fuente en las esencias y no recíprocamente. Por su parte, la concepción de Kripke obliga a repensar nociones supuestamente evidentes sostenidas por Husserl, como la equivalencia a priori/necesario, a posteriori/contingente, así como los lazos entre concebibilidad y posibilidad. Tomando distancia respecto de la posición de Husserl, se (...) rechaza aquí la variación eidética como método único y se enfatiza finalmente el valor de la discusión razonada. (shrink)

Introspection presents our phenomenal states in a manner otherwise than physical. This observation is often thought to amount to an argument against physicalism: if introspection presents phenomenal states as they essentially are, then phenomenal states cannot be physical states, for we are not introspectively aware of phenomenal states as physical states. In this article, I examine whether this argument threatens a posteriori physicalism. I argue that as along as proponents of a posteriori physicalism maintain that phenomenal concepts present (...) the nature of their referents in a partial and incomplete manner, a posteriori physicalism is safe. (shrink)

According to a posteriori ethical intuitionism, perceptual experiences can provide non-inferential justification for at least some moral beliefs. Moral epistemology, for the defender of AEI, is less like the epistemology of math and more like the epistemology of tables and chairs. One serious threat to AEI comes from the phenomenon of cognitive penetration. The worry is that even if evaluative properties could figure in the contents of experience, they would only be able to do so if prior cognitive states (...) influence perceptual experience. Such influences would undermine the non-inferential, foundationalist credentials of AEI. In this paper, I defend AEI against this objection. Rather than deny that cognitive penetration exists, I argue that some types of cognitive penetrability are actually compatible with AEI's foundationalist structure. This involves teasing apart the question of whether some particular perceptual process has justification-conferring features from the question of how it came to have those features in the first place. Once this distinction is made, it becomes clear that some kinds of cognitive penetration are compatible with the non-inferential status of moral perceptual experiences as the proponent of AEI claims. (shrink)

A posteriori Moral Naturalism posits a posteriorimoral/naturalistic identities. Versions of this view thatposit necessary identities purport to rely on theKripke/Putnam doctrine of scientific essentialism.Versions that posit only contingent identities requirethat moral terms are non-rigid designators. I argue thatmetaethics does not fall within the scope of scientificessentialism and that moral terms are not non-rigid designators.

A lot of good philosophy is done in the armchair, but is nevertheless a posteriori. This paper clarifies and then defends that claim. Among the a posteriori activities done in the armchair are assembling and evaluating commonplaces; formulating theoretical alternatives; and integrating well-known past a posteriori discoveries. The activity that receives the most discussion, however, is the application of theoretical virtues to choose philosophical theories: the paper argues that much of this is properly seen as a (...) class='Hi'>posteriori. (shrink)

At the time that Quine wrote "Two Dogmas" an attack on analyticity was considered a simultaneous attack on the very idea of necessary truth. This all changed with Kripke's revival of a non-epistemic, non-linguistic notion of necessity. My paper discusses the question whether we can take Kripke one step further and free analyticity from its epistemic ties, thereby reinstating a notion of analyticity that is immune to Quine's attack, and compatible with his epistemic holism. I discuss this question by examining (...) Tyler Burge's claim that truths of meaning depend on features of the external environment and are a posteriori. I argue that although Burge's construal of analyticity circumvents Quine's objections, it is not well-motivated philosophically and has problematic implications. Kripke's strategy with respect to necessity, I conclude, is not easily transferable to analyticity. (shrink)

Recent criticisms of non-reductive accounts of color assume that the only arguments for such accounts are a priori arguments. I put forward a posteriori arguments for a non-reductive account of colors which avoids those criticisms.

I argue that conventionalists should construe a posteriori necessity as restricted necessity. I take Sidelle’s defence of the conventionalist explanation of a posteriori necessity against the contingency problem as the starting point. Sidelle construes a posteriori necessity as unrestricted necessity and then argues that a posteriori necessity is to be considered under a fixed convention and is thus irrelevant to the contingent nature of our linguistic conventions. I offer a different solution to the contingency problem. I (...) argue that conventionalists should construe a posteriori necessity as restricted necessity based upon a use-based meta-semantic picture. Restricted necessity is contingent in a broader sense and does not conflict with the contingency of conventions. My solution allows conventionalists to explain a posteriori necessity as restricted necessity. I show that the realist’s arguments for a posteriori necessity are unconvincing in regard to real modal features and a posteriori necessity as unrestricted necessity. We thus have good reason to continue to accept a posteriori necessity as restricted necessity under the conventionalist explanation. (shrink)

Arguably, the proposition that Mark Twain is Samuel Clemens and the proposition that water is H2O are both a posteriori. Nevertheless, they both seem to be necessary. Ever since Davies and Humberstone :1–31, 1980), it has been known that two-dimensional semantics can account for this fact. But two-dimensionalism isn’t the only theory on the market that purports to do so. In this paper, I will look at two alternatives, one by Scott Soames and one by Kathrin Glüer-Pagin and Peter (...) Pagin, and argue that both of them fail. Regarding the former, I argue that the conceptually possible but metaphysically impossible worlds one is required to postulate are hard to conceive of on closer inspection. As for the latter, the proposal doesn’t work for certain modal sentences, and I show that it cannot be easily amended. (shrink)

El presente artículo se propone analizar una serie de llamativas coincidencias entre el pensamiento tardío de Husserl y el pensamiento temprano de Heidegger –en particular en torno a tópicos como la muerte, la finitud, la negatividad y la posibilidad– a partir de la puesta en primer plano de un problema metodológico crucial para la fenomenología: el de la legitimación de las propias descripciones del ámbito de la subjetividad originaria. Ello conduce a Husserl, pretendo mostrar, al abandono de una noción estrecha (...) de donación y legitimación asociada a la intuitividad y al desarrollo de una fenomenología constructiva centrada en la pregunta por lo inconstituible y por el modo en que la esfera propiamente constituyente puede darse, si bien siempre indirectamente, en la experiencia, en el sentido de lo que Montavont ha llamado un “trascendental a posteriori”. Es allí donde las coincidencias con Heidegger saldrán a la luz. (shrink)

Illusionists and a posteriori physicalists agree entirely on the metaphysical nature of reality — that all concrete entities are composed of fundamental physical entities. Despite this basic agreement on metaphysics, illusionists hold that phenomenal consciousness does not exist, whereas a posteriori physicalists hold that it does. One explanation for this disagreement would be that either the illusionists have too demanding a view about what consciousness requires, or the a posteriori physicalists have too tolerant a view. However, we (...) will argue that this divergence of opinion is merely an upshot of the semantic indeterminacy of the term 'conscious' and its cognates. We shall back up this diagnosis by showing how semantic indeterminacy of the kind in question is a pervasive feature of language. By illustrating this pattern with a range of historical examples, we shall show how the dispute between the illusionists and a posteriori physicalists is one instance of a common kind of terminological imprecision. The disagreement between them is thus not substantial. In effect, the two sides differ only about how to make an indeterminate term precise. The moral is that they should stop looking for arguments designed to settle the dispute in their favour. (shrink)

There are two constraints on any functionalist solution to the Mind-Body Problem construed as an answer to the question, “What is the relationship between the mental properties and relations (hereafter, simply the mental properties) and physical properties and relations?” The first constraint is that it must actually address the Mind-Body Problem and not simply redefine the debate in terms of other, more tractable, properties (e.g., the species-specific property of having human-pain). Such moves can be seen to be spurious by the (...) very multiple-realizability intuitions that motivate functionalism in the first place. For, according to those intuitions, it is possible for a being to experience pain, have beliefs, etcetera, and yet not only to be of a different species, but to have an entirely different material constitution from human beings. (shrink)

I defend this claim that some natural essences can be known (only) a pos- teriori against two philosophers who accept essentialism but who hold that essences are known a priori: Joseph LaPorte, who argues from the use of kind terms in science, and E. J. Lowe, who argues from general metaphysical and epistemological principles.

I argue that Fregeanism with respect to proper names—the view that modes of presentation are relevant to the contents of proper names—is able to account for the thesis that there are necessarily true a posteriori identity propositions such as the one expressed in “Hesperus is identical with Phosphorus”, whereas the Direct Reference Theory—according to which the semantic function of certain expressions, e.g., proper names, is only to pick out an object —is able to deal with only their necessary truth. (...) Thus, at least in so far as necessarily true a posteriori identity propositions are concerned, Fregeanism should be preferred to the Direct Reference Theory. (shrink)

Disjunctivism in philosophy of perception maintains that whereas veridical perceptions are relational states involving objects of the external world, illusions and hallucinations are non-relational states of the subjects. Veridical and non veridical perceptions could be subjectively indistinguishable, but this fact would not be able to support fundamental psychological explanations. Disjunctivism has to face some important problems. The aim of this paper is to explore a peculiar elaboration of disjunctivism able to face them. Our proposal intends to be substantive, offering a (...) counterfactual explanation of the differences between veridicaland non veridical perceptions. We will arrive to an a posteriori disjunctivism for some relevant types of perceptual experiences. The a posteriori character of our position will be consequent with the external nature of the intentional objects of veridical perceptions. But our disjunctivism will be concerned only with types of perceptual experiences. That way, it could make room for many sorts of internalist psychological explanations in the context of a general disjunctivist approach. (shrink)

A consideration of the benefits of taking physicalism to be necessarily true if true, against the standard view that physicalism is at best contingently true. Presented at the 2006 Central Division meeting of the APA, in the session Themes from Jaegwon Kim, sponsored by the Society for Asian and Asian-American Philosophy.

In this chapter I consider three different positions on the a priori/a posteriori distinction that have been attributed to Hegel, specifically in the context of the epistemology of the metaphysical claims he defends in his Realphilosophie. I outline and briefly provide evidence for a reading of Hegel that understands him to retain the distinction in question, but to hold that the metaphysical claims he defends in the context of his philosophy of nature and his philosophy of spirit typically involve (...) elements of both a priori and a posteriori knowledge. I then defend this interpretation against two competitors. The first of these also takes Hegel to retain the distinction, but holds that the conclusions of his Realphilosophie, like those of his logic, are principally to be understood as known a priori. The second takes Hegel to abandon the a priori/a posteriori distinction altogether. I argue that these alternatives are less compelling. (shrink)

The absence of a necessary connection in singular causation is a key step in the Humean argument against any form of necessity in causation. I argue that Hume's defence of this step is unsuccessful, and that the step could be skipped, accepting the possibility of necessary a posteriori truths. Still this does not suffice to guarantee a necessary connection in singular causation. Necessary a posteriori truths should be backed by necessary a priori truths. Thus, a main object of (...) this paper is to argue that an a priori philosophical concept of causality involves a necessary connection between its terms. (shrink)

Dualists say plausible things about our mental concepts: there is a way of thinking of pain, in terms of how it feels, which is independent of causal role. Physicalists make attractive ontological claims: the world is wholly physical. The attraction of a posteriori physicalism is that it has seemed to do both: to agree with the dualist about our mental concepts, whilst retaining a physicalist ontology. In this paper I argue that, in fact, a posteriori physicalism departs from (...) the dualist's intuitive picture of our phenomenal concepts in just as radical a manner as more traditional forms of physicalism. Whereas the physicalism of David Lewis and David Armstrong is counterintuitive in holding that our only way of thinking about pain is in terms of its causal role, the physicalism of David Papineau and Brian Loar departs from common sense in holding that our phenomenal concept of pain is opaque: thinking of pain in terms of how it feels reveals nothing of what it is for something to feel pain. The arguments of David Chalmers and Frank Jackson against a posteriori physicalism involve general claims about all concepts. In contrast, my argument makes a claim only about phenomenal concepts: phenomenal concepts are not opaque. (shrink)

We provide an account of necessary a posteriori identity statements that relies upon Perry’s multipropositionalism. On our account an utterance of, e.g., ‘Hesperus is Phosphorus’, semantically makes available several propositions, one of which is necessary (and a priori) and another of which is a posteriori (and contingent). Since our view resembles two-dimensionalism, one might assume that it is undermined by the sorts of nesting arguments that Soames and others have raised against two-dimensionalism. We demonstrate, however, that our account (...) is immune to such nesting arguments. (shrink)

In this paper I argue that it is not a priori that all the laws of nature are contingent. I assume that the fundamental laws are contingent and show that some non-trivial, a posteriori, non-basic laws may nonetheless be necessary in the sense of having no counterinstances in any possible world. I consider a law LS (such as 'salt dissolves in water') that concerns a substance S. Kripke's arguments concerning constitution show that the existence of S requires that a (...) certain deeper level law or variants thereof hold. At the same time, that law and its variants may each entail the truth of LS. Thus the existence of S entails LS. Consequently there is no world in which S exists and fails to obey LS. I consider the conditions concerning the fundamental laws that would make this phenomenon ubiquitous. I conclude with some consequences for metaphysics. (shrink)

Some necessary truths are a posteriori. That’s widely agreed and is presumed here. Their existence might appear to show that discoveries about how things are in fact—about how things actually are—can lead to discoveries about all the ways things might be, about the nature of logical space. I detail one way of resisting this conclusion for a number of examples, and the implications of Twin Earth for the issue. Central is the notion of a Cambridge discovery.

La séparation parentale apparaît comme un événement fréquent, mais néanmoins majeur dans la vie d’un sujet, surtout à l’adolescence. Comment se conjuguent adolescence et les problématiques psychiques (œdipienne et de perte) et relationnelles qu’elle implique, avec la séparation parentale? L’article discute ici le cas d’Adèle, âgée de 22 ans, pour qui la séparation des parents a eu lieu lorsqu’elle avait 16 ans. Adèle a été rencontrée trois fois dans le contexte d’une recherche. Les éléments cliniques recueillis lors des entretiens mènent (...) sur la voie d’effets négatifs toujours actuels en lien avec la séparation parentale et qui se télescopent avec une sensibilité préalable à la perte. On peut repérer, dans le cas d’Adèle, une instabilité identificatoire, un clivage des figures parentales, une accentuation de l’ambivalence à l’égard du parent de sexe opposé, une errance scolaire et des difficultés relationnelles. Ce cas clinique illustre la nécessité de procéder à un repérage des adolescents en souffrance suite à la séparation parentale et d’offrir un accompagnement aux parents. (shrink)

There is a good a priori argument for the doctrine of the Trinity, from the need for any divine being to have another divine being to love suffi ciently to provide for him a third divine being whom to love and by whom to be loved. But most people who have believed the doctrine of the Trinity have believed it on the basis of the teaching of Jesus as interpreted by the church. The only reason for believing this teaching would (...) be if Jesus led the kind of life which a priori we would expect an incarnate God to live in order to identify with our suffering, make atonement for our sins, and to reveal truth to us; culminated by a miracle which God alone could do and which would also authenticate the teaching. Given good a posteriori evidence for the existence of God, there is enough historical evidence to make it probable that Jesus did live that sort of life, and so to believe the doctrine of the Trinity. (shrink)

This article discusses the role of a priori and a posteriori knowledge and methods in metaphysics and metametaphysics. Issues discussed include the viability of the distinction, the continuity of a priori and a posteriori methods, connections to modal epistemology, and the role of the distinction for science and naturalistic metaphysics.

Colin McGinn; XI*—A priori and a posteriori Knowledge, Proceedings of the Aristotelian Society, Volume 76, Issue 1, 1 June 1976, Pages 195–208, https://doi.org/.

In this paper, I reevaluate Kripke’s arguments for the necessary a posteriori contra a Kantian pure modal rationalism according to which modal cognition is a priori. I argue that Kripke’s critique of Kant suggests an impure but nevertheless ambitious modal rationalism according to which the basis of modal cognition remains a priori. I then argue that Kripke’s critique of pure modal rationalism does not go deep enough. More specifically, I argue that certain conditional modal judgments, which Kripke regards as (...) a priori, are, in fact, a posteriori. An example is the conditional modal judgment that if gold is a metal, then it is necessary that gold is a metal (if gold exists). However, Chalmers has developed a general frontloading strategy for turning a posteriori conditionals into a priori ones. So, I consider whether the frontloading strategy may be applied in a development of a modest modal rationalist account of the necessary a posteriori. Although the frontloading strategy is attractive for the modal rationalist, I argue for a twofold conclusion. First, I conclude that a posteriori conditionals constitute a serious and unanswered challenge to modal rationalists. Second, I conclude that the frontloading strategy does not by itself provide a response to this challenge and that substantiating the strategy is problematic. (shrink)

A sequence x=xn:nω of elements of a complete Boolean algebra converges to a priori if lim infx=lim supx=b. The sequential topology τs on is the maximal topology on such that x→b implies x→τsb, where →τs denotes the convergence in the space — the a posteriori convergence. These two forms of convergence, as well as the properties of the sequential topology related to forcing, are investigated. So, the a posteriori convergence is described in terms of killing of tall ideals (...) on ω, and it is shown that the a posteriori convergence is equivalent to the a priori convergence iff forcing by does not produce new reals. A property of c.B.a.’s, satisfying -cc -cc and providing an explicit definition of the a posteriori convergence, is isolated. Finally, it is shown that, for an arbitrary c.B.a. , the space is sequentially compact iff the algebra has the property and does not produce independent reals by forcing, and that implies P is the unique sequentially compact c.B.a. in the class of Suslin forcing notions. (shrink)

The essence of the associated-proposition strategy is to distinguish the necessary proposition _expressed by_ a sentence.

The meta-problem of consciousness is the problem of explaining why we believe that there is a hard problem of consciousness. A solution to the former promises to take us one step closer to solving the latter. While many hope for a physicalist realist solution to the meta-problem, I argue that the two prominent physicalist realist positions in the literature, orthodox Russellian and type-B physicalism, cannot deliver a solution. I then introduce a posteriori Russellian physicalism, a Russellian version of the (...) phenomenal concept strategy, and show that it can overcome the difficulties of traditional Russellian and type-B physicalism. If successful, the paper shows that physicalists need not turn to illusionism because the prospects for a physicalist realist answer to the meta-problem are bright. (shrink)

The article discusses Saul Kripke’s influential theories of a posteriori necessary truths and natural kinds. With respect to the statements of identity involving proper names, it is argued that although their truth is a posteriori and necessary in the specific sense of counterfactual invariance, this is of no significance for substantial philosophical issues beyond the philosophy of language, because this counterfactual invariance is a trivial consequence of the use of proper names as rigid designators. The case is made (...) that the expansion of the realm of necessary a posteriori truths to the statements of theoretical identity that involve “natural kind terms”, as well as the Kripkean essentialist theory of natural kinds, have no weighty argumentative support and fit badly both with science and language practice. This sets the stage for the development of an appropriately sophisticated “descriptivist” account of meaning and reference that would be better suited for a widened range of Kripke-Putnam style thought experiments. The general outlines of such a descriptivist account are provided. (shrink)

According to a posteriori physicalism, phenomenal properties are physical properties, despite the unbridgeable cognitive gap that holds between phenomenal concepts and physical concepts. Current debates about a posteriori physicalism turn on what I call “the perspicuity principle”: it is impossible for a suitably astute cognizer to possess concepts of a certain sort—viz., narrow concepts—without being able to tell whether the referents of those concepts are the same or different. The perspicuity principle tends to strike a posteriori physicalists (...) as implausibly rationalistic; further, a posteriori physicalists maintain that even if the principle is applicable to many narrow concepts, phenomenal concepts have unique features that render them inferentially isolated from other narrow concepts ). I argue, on the contrary, that the case for the perspicuity principle is quite strong. Moreover, not only have versions of the PCS repeatedly failed, likely, all versions will, given the strange combination of lucidity and opacity that the PCS has to juggle. I conclude that a posteriori physicalists currently lack a principled objection to classic anti-physicalist arguments. (shrink)

There is a widespread assumption that the classical work in philosophical semantics of Saul Kripke (1980) and Hilary Putnam (1975) has taught us that the essences of natural kinds of substances, such as water and gold, are discoverable only a posteriori by scientific investigation. It is such investigation, thus, that has supposedly revealed to us that it is an essential property of water that it is composed of H2O molecules. This is the way in which Scott Soames, in a (...) recent paper, makes the point in the case of water and H2O: [Here is] how a Kripkean explanation of the necessary a posteriority of [‘Water = H2O’] would go – or at any rate my version of it. The account holds that ‘water’ is a non-descriptive, directly-referential term designating a substance – where substances are taken to be physically constitutive kinds (instances of which share the same basic physical constitution). It is further assumed that a kind of this sort may have different instances in different world-states, and that if a and b are kinds with the same instances in all possible world-states, then a is b. These are clearly metaphysical assumptions, to which we add the natural corollary that for any substance, s, if, in some possible world-state, instances of s have a certain molecular structure, then instances of s have that structure in every world-state. In other words, we assume that it is an essential property of a substance that instances of it have the molecular structure they do. From this it follows that [‘Water = H2O’] is necessary if true, and that ‘H2O’– which I take to be equivalent to ‘the substance instances of which have a molecular structure with two hydrogen atoms and one oxygen atom’– is a rigid designator. Being true, [‘Water = H2O’] is, therefore, necessary. Since knowing the proposition it expresses requires knowing of a certain substance that its instances have a particular chemical structure, [‘Water = H2O’] is knowable only a posteriori. (Soames 2007: 36). (shrink)

In the mid twentieth century, logical positivists and many other philosophers endorsed a simple equation: something was necessary just in case it was analytic just in case it was a priori. Kripke’s examples of a posteriori necessary truths showed that the simple equation is false. But while positivist-style inferentialist approaches to logic and mathematics remain popular, there is no inferentialist account of necessity a posteriori. I give such an account. This sounds like an anti-Kripkean project, but it is (...) not. Some of Kripke’s remarks even suggest this kind of approach. This inferentialist approach reinstates neither the simple equation nor pure conventionalism about necessity a posteriori. But it does lead to something near enough, a type of impure conventionalism. In recent years, metaphysically heavyweight approaches to modality have been popular, while other approaches have lagged behind. The inferentialist, impure conventionalist theory of necessity I describe aims to provide a metaphysically lightweight option in modal metaphysics. (shrink)

Reduction between theories in physics is often approached as an a priori relation in the sense that reduction is often taken to depend only on a comparison of the mathematical structures of two theories. I argue that such approaches fail to capture one crucial sense of “reduction,” whereby one theory encompasses the set of real behaviors that are well-modeled by the other. Reduction in this sense depends not only on the mathematical structures of the theories, but also on empirical facts (...) about where our theories succeed at describing real systems, and is therefore an a posteriori relation. (shrink)