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)

Two sentences express the same proposition if they are synonymous; they express the same statement if they attribute the same properties to the same objects at the same time (however objects and times are picked out). Neither propositions nor statements are necessary a posteriori. Suggested examples of the necessary a posteriori, such as "Hesperus is Phosphorus", or "water is H2O", only appear to be such because of a confusion between proposition and statement.

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)

There is a form of argument for a certain kind of essentialist conclusion which appears not to depend upon any appeal to intuition. Identity statements involving natural kind terms are often adverted to in the literature as examples of the necessary a posteriori, and it can appear as though the essentialist is on very strong ground with respect to these claims. It is not merely that they are apt to strike one as plausible in the light of philosophical (...) arguments or modal intuitions; rather, they appear to be provable, given only fairly trivial logical principles and uncontroversial scientific truths. This paper attempts to counter the claim, made particularly convincing by the work of Saul Kripke, that this indeed the case. (shrink)

Some of Tichý's conclusions rest on an assumption about substitutivity which Kripke would not accept. If we grant the assumption, then Tichý successfully shows that we can discover true identity statements involving names a priori, but not that we can discover a priori what properties things have essentially. Many of Tichý's arguments require an implausible rejection of the possibility of indirect belief as described in Section III. 25Are there necessary a posteriori propositions? I have argued that we certainly (...) can discover necessary propositions a posteriori, but have left it an open question whether there are necessary propositions which we can only discover a posteriori.What effect do the considerations here presented have on the positivist doctrine that the a priori and the necessary coincide? My explanation of how we discover necessary propositions a posteriori involves our believing them indirectly, in virtue of believing contingent propositions. I would argue that Kripke's examples of the contingent a priori involve, similarly, our believing the contingent propositions in directly, in virtue of believing necessary propositions.This suggests that a reformulation of the positivist thesis along something like the following lines may well be correct. Let us say that someone directly believes a proposition just in case he could not fail to believe it without being in a different cognitive state. Then perhaps one can directly believe a proposition on the basis of a priori evidence only if it is necessary, and can directly believe a proposition on the basis of a posteriori evidence only if it is contingent. (shrink)

Alvin Plantinga has recently argued that there are certain propositions which are necessary but known only a posteriori. If Plantinga is correct then he has shown that the traditional view that all necessary truths are knowable a priori is false. Plantinga's examples deserve special attention because they differ in important respects from other proposed examples of necessary a posteriori truths. His examples depend on a certain conception of possible worlds and in particular on his conception (...) of the actual world. It will be argued that these examples of necessary a posteriori propositions can be understood in two different ways. According to one way of understanding Plantinga, the propositions turn out to be contingent a posteriori truths, and according to the other way they turn out to be necessary a priori truths. The plausibility of Plantinga's position is due to a confusion between the two possible interpretations. (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.

Roderick Chisholm addressed the issue of the necessary a posteriori on at least three occasions and, characteristically, modified his views over time. He first advanced a three-stage argument that concluded that no necessary truths are known a posteriori. Without abandoning that argument, he later weakened its conclusion, claiming only that not all knowledge of necessary truths is a posteriori. In the main, this paper is a detailed critical exposition of Chisholm's arguments. However, it also (...) picks up on some suggestive remarks of Chisholm's, draws them out, and explores them. (shrink)

In ‘Kripke on epistemic and metaphysical possibility: two routes to the necessary a posteriori’, Scott Soames identifies two arguments for the existence of necessary a posteriori truths in Naming and Necessity . He argues that Kripke's second argument relies on either of two principles, each of which leads to contradiction. He also claims that it has led to ‘two-dimensionalist’ approaches to the necessary a posteriori which are fundamentally at odds with the insights about meaning (...) and modality expressed in NN. I argue that the alleged second argument is not in NN. I identify the mistakes that lead to Soames' misinterpretation. (shrink)

This paper is an examination of the contingent a priori and the necessary a posteriori. In particular, it considers -- and assesses -- the criticisms that Nathan Salmon makes of the views of Saul Kripke.

Kripke claims that there are necessary a posteriori truths and contingent a priori truths. These claims challenge the traditional Kantian view that (K) All knowledge of necessary truths is a priori and all a priori knowledge is of necessary truths. Kripke’s claims continue to be resisted, which indicates that the Kantian view remains attractive. My goal is to identify the most plausible principles linking the epistemic and the modal. My strategy for identifying the principles is to (...) investigate two related questions. Are there compelling general supporting arguments for (K)? Are there decisive counterexamples to (K)? My investigation uncovers two intuitively plausible principles that are not open to decisive counterexamples but which enjoy no compelling independent support. (shrink)

SCIENTISTS HAVE DISCOVERED that water is H2O. Water is H2O is true. But is it a necessary truth? In other words, is it true in all possible worlds? Some people think it is. For example Hilary Putnam, in his well-known Twin Earth argument, concludes that "water is H2O" is necessarily true; thus a liquid which phenomenally resembles H2O and fits the description of water in almost all aspects, but has the chemical formula XYZ, cannot be water. Saul Kripke has (...) made a similar claim about the necessary identity between water and H2O. Because this type of truth is based on empirical discoveries, Kripke calls truths of this sort "necessary a posteriori." The thesis shared by Putnam and Kripke has two premises: a realist view that natural kinds exist independently of human cognition, and a theory of direct reference of natural kind terms. Opposing the view that natural kind terms pick out objects through descriptions, Putnam and Kripke hold that natural kind terms pick out natural kinds in the world in a direct way. Based on these two premises, they argue that, if two natural kind terms, A and B, designate the same thing in the world, "A = B" expresses a necessary identity. (shrink)

According to Naming and Necessity, proper names usually work referentially as rigid designators. In this paper, I argue that proper names have also attributive uses that systematically emerge in particular contexts. Attributive uses are then exploited to show that simple identity claims (such as “Hesperus is Phosphorus”) are open to a double interpretation. The main aim of the paper is arguing that the impression that certain true identities are a posteriori is mostly due to one of the two readings, (...) a reading according to which, however, the expressed truth is only contingently true. (shrink)

We think that Kripke’s arguments that there are contingent a priori truths and that there are necessary a posteriori truths about named and essentially described entities fail. They fail for the reasons that there are ambiguities in each of the three eases. In the first ease, what is known apriori is not what is contingent. In the latter two cases, what is necessary or essential is not what is known a posteriori.

We think that Kripke’s arguments that there are contingent a priori truths and that there are necessary a posteriori truths about named and essentially described entities fail. They fail for the reasons that there are ambiguities in each of the three eases. In the first ease, what is known apriori is not what is contingent. In the latter two cases, what is necessary or essential is not what is known a posteriori.

Se afirma que los enunciados necesarios a posteriori, propuestos por S. Kripke, exigen una comprensión débil de la necesidad; esto quiere decir: a) existencia contingente del designatum 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 información empírica. Finalmente, (...) se defiende que la distinción entre denotación y designación permite sostener que la necesidad débil se aplica a las instancias de la clase, y no a esta, con lo que se evita el indeterminismo referencial. The article states that a posteriori necessary sentences as proposed by S. Kripke require a weak understanding of necessity. This means: a) contingent existence of designatum, and b) rationalist dependence on a priori logical principles, particularly those of difference and identity. The main consequence is that a posteriori necessary sentences correspond to instances of these logical principles. Contrary to rationalism, this does not require that these be a priori sentences, given that their justification requires empirical information. Finally, the article argues that the distinction between denotation and designation supports the idea that weak necessity applies to instances of the class, and cannot be applied to the class itself, thus avoiding referential indeterminism. (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)

Is experiential evidence irrelevant to acceptance or rejection of belief in the existence of a Divine Being? Charles Hartshorne answers that it is indeed irrelevant, and this answer has an initial and, for me, continuing surprising ring to it. Specifically, Hartshorne makes two distinguishable claims: the traditional allegedly a posteriori arguments, the teleological and cosmological, are in fact incompatible with empiricist methodology and are disguised ontological arguments; the conception of God as necessary being demands that belief in such (...) a being's existence or non-existence in no way depend upon empirical evidence. On the contrary, I shall argue, first, that empirical evidence for God is truly empirical and second, that there is no incompatibility between empirical evidence and necessary existence. My argument will involve an attempt to understand and clarify somewhat the very difficult concepts of ‘experience’ and ‘necessity’ as they arise in the context of religious epistemology. I wish to make clear at the outset that my aim is not to eliminate ontological arguments for God in favour of empirical arguments, for I believe that Hartshorne's work on the modal ontological argument contributes substantially to providing grounds for reasonable belief in theism. Rather, my purpose is to show that ontological and empirical patterns of theistic argumentation are neither incompatible with each other nor reducible to each other. (shrink)

The once deeply held conviction that all necessary truths are known a priori is now widely, although by no means universally agreed to have been subjected to penetrating, if not devastating criticism. Scott Soames, for example, on behalf of Saul Kripke, and indirectly of Hilary Putnam, argues that in respect of natural kinds, the introduction of basic essentialist assumptions grounded in our pre-theoretical habits of thinking and speaking – for example, that atomic or molecular structure provides the underlying essence (...) of a substance – allows a sentence like "water = H 2 0," in which the identity sign is flanked by rigid designators to express a metaphysically necessary truth. Yet doubts and puzzlement remain over the status of a posteriori necessities, including those relating to an individual's origin. This paper considers some prominent criticisms that have been made of the Kripke–Putnam approach by A. J. Ayer and Frank Ebersole among others and reveals in what respects they are valid, where they are misplaced, and, perhaps more importantly, why the most valuable aspect of this approach can be seen to reflect aspects of our scientific procedures that do indeed point towards an application for a distinction that roughly mirrors that between epistemic and metaphysical possibility, yet one that is grounded instead in the nature of our actual practices. (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)

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.

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)

Most contemporary analytic philosophers of language and mind accept the view that there is a wide class of terms, “natural kind terms”, which includes names of substances (the most common example is “water”), of species of animals, and of many other kinds of things in nature, whose meaning and reference is determined in the way explained by the theory developed in the 1970s by Saul Kripke and Hilary Putnam. The theory is often referred to as “the Kripke-Putnam theory” and is (...) supposed to have such achievements as the overthrow of the earlier dominant Fregean theory of word-meanings (dubbed “descriptivism” by Kripke) as determined by the concepts in our minds, providing support for the “externalist” approach to linguistic meanings (in line with Putnam’s claim that “"Meanings" just ain’t in the head”), and the discovery that there is a wide class of truths (such as that water is H20) that are both a posteriori and necessary. Although the priority in the development of this theory belongs to Kripke, it could hardly gain such a wide acceptance without contributions by Putnam, which turned out to be very influential. However, the habitual idea of “the Kripke-Putnam theory”, as one theory, tends to play down the differences between Putnam’s and Kripke’s approaches and to hush up the fact that in his late works, of 1983 and 1990, Putnam revised and abandoned pretty much of his “Kripkean” views of 1970-ies; in particular, repudiated the pride of Kripke’s theory, the idea of necessary a posteriori truths. This article makes critical analysis and evaluation of Putnam’s ideas and arguments usually credited as important contributions to “the Kripke-Putnam theory”, and highlights the main points of the revision in late Putnam’s works. The case is made that Putnam's famous argument for externalism about meanings, the Twin-Earth thought experiment, is question-begging, fails to do justice to likely changes in the meanings of words with the development of knowledge, and conflicts with the linguistic practice in the relevantly similar case of “jade”. Putnam's argument for externalism from the division of linguistic labour is not cogent too, because “semantic deference” is itself a matter of what is there in “heads” - of some (non-expert) heads deferring to other (recognised as expert) heads. Eventually, on close inspection and in the light of Putnam's later reexplanation and revision, his account of meaning and reference turns out to be a sophisticated variety of conceptualism/internalism. (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)

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)

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)

I argue that Anselmians ought to abandon traditional Anselmianism in favor of Moderate Anselmianism. Moderate Anselmianism advances the view that a being x = God iff for every essential property P of x, it is secondarily necessary that x has P, for most essential properties of x, it is not primarily necessary that x has P and the essential properties of x include omnipotence, omniscience, perfect goodness and necessary existence. Traditional Anselmians have no cogent response to most (...) a priori atheological arguments. But a priori atheological arguments present no serious problem for moderate Anselmians. Unlike traditional Anselmianism, Moderate Anselmianism explains why a priori atheological arguments can be convincing and nonetheless illusory. (shrink)

The terms "a priori" and "a posteriori" refer primarily to how or on what basis a proposition might be known. A proposition is knowable a priori if it is knowable independently of experience. A proposition is knowable a posteriori if it is knowable on the basis of experience. The a priori/a posteriori distinction is epistemological and should not be confused with the metaphysical distinction between the necessary and the contingent or the semantical or logical distinction between (...) the analytic and the synthetic. Two aspects of the a priori/a posteriori distinction require clarification: the conception of experience on which the distinction turns; and the sense in which a priori knowledge is independent of such experience. The latter gives rise to important questions regarding the positive basis of a priori knowledge. (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)

Chalmers argues that zombies are possible and that therefore consciousness does not supervene on physical facts, which shows the falsity of materialism. The crucial step in this argument – that zombies are possible – follows from their conceivability and hence depends on assuming that conceivability implies possibility. But while Chalmers’s defense of this assumption – call it the conceivability principle – is the key part of his argument, it has not been well understood. As I see it, Chalmers’s defense of (...) the conceivability principle comes in his response to the so-called objection from a posteriori necessity. The defense aims at showing that there is no gap between conceivability and possibility since no such gap can be generated by necessary a posteriori truths. I will argue that while Chalmers is right to the extent that there is no gap between conceivability and possibility within the standard Kripkean model of a posteriori necessity, his general conclusion is not justified. This is because the conceivability principle might be inconsistent with a posteriori necessity understood in some non-Kripkean way and Chalmers has not shown that no such alternative understanding of a posteriori necessity is available. (shrink)

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

This article aims to provide an a posteriori argument from love for the Trinity. A reformulation of the argument from love is made by proposing a novel version of the argument that is situated within an objective, empirical, natural theological framework. Reformulating the argument in this specific manner will enable it to ward of an important objection that is often raised against it, and ultimately render this argument of great use in establishing the necessity of the Trinity.

This paper will look at three closely interrelated questions about necessary a posteriori identities, in particular concerning natural kinds. First-ly, what is the semantic phenomenon responsible for a posteriori necessities in general, and theoretical identity statements concerning natural kinds in particular? I will argue that rigidity, as it is usually defined, cannot do the job for theoretical identity statements. Rather, a posteriori necessities are grounded in a semantic phenomenon that I have in earlier work called actuality-dependence. (...) Secondly, what is the basis for this semantic phenomenon? In other words, what makes a given expression actuality-dependent, and thereby fit for appearing in a posteriori necessities? I will argue that actuality-dependence is grounded in our linguistic patterns and dispositions of application and interpretation. Thirdly and finally, what does this tell us about what essences are, and how we possess knowledge of them? I will claim that the view I am proposing gives direct support to a conferralist view of essences, at least when it comes to natural kinds. Moreover, the explanation of a posteriori necessities does not rely on independent essentialist premises; however, it does rely on essentialist beliefs or expectations on the part of ordinary speakers. (shrink)

In Meaning and Necessity (1947/1950), Carnap advances an intensional semantic framework on which modal claims are true in virtue of semantical rules alone, and so are a priori. In 'Empiricism, Semantics, and Ontology' (1950), Carnap advances an epistemic-ontological framework on which metaphysical claims are either trivial or meaningless, since lacking any means of substantive confirmation. Carnap carried out these projects two decades before Kripke influentially argued, in Naming and Necessity (1972/1980), that some modal claims are true a posteriori. How (...) should a neo-Carnapian respond to Kripke's results? Some (notably, Chalmers and Jackson, in their 2001) have suggested that an extension of intensional semantics along lines of "epistemic two-dimensionalism" can accommodate Kripke's results while largely preserving commitment to the semantics-based a priority of modal claims. Here we consider how best to implement this suggestion, and how the resulting semantics fits with Carnap's second project. We find that the most promising (and most Carnapian!) post-Kripke version of Carnap’s semantics---abductive two-dimensionalism---presupposes an epistemology which undermines Carnap's metaphysical anti-realism. (shrink)

The problem of nonreflectors perceived as colored is the central problem for Byrne & Hilbert's (B&H's) physicalism. Vision scientists and other interested parties need to consider the motivation for their account of “productance physicalism.” Is B&H's theory motivated by scientific concerns or by philosophical interests intended to preserve a physicalist account of color as a posteriori necessary?