Online research in philosophy

After a brief review of the notions of necessity and a priority, this paper scrutinizes Kripke's arguments for supposedly contingent a priori propositions and necessary a posteriori propositions involving proper names, and reaches a negative conclusion, i.e. there are no such propositions, or at least the propositions Kripke gives as examples are not such propositions. All of us, including Kripke himself, still have to face the old question raised by Hume, i.e. how can we justify the necessity and universality of general statements on the basis of sensory or empirical evidence?

In Naming and Necessity, Kripke argues that clearly conceived (or imagined) scenarios that seem to be counterexamples to a posteriori identity theses can indeed count as evidence against them—but only if, after reflection on our understanding of their constituent terms and the relevant empirical facts, we find that they cannot be acceptably reconstrued as intuitions about something else. This makes trouble for phenomenalphysical identity statements such as ‘pain is C-fiber stimulation’, since most agree that such statements cannot be so reconstrued—and thus some materialists reject Kripke’s account of the link between conceivability and possibility entirely. In my view, however, this is a mistake, since it impoverishes our resources for evaluating a posteriori modal claims;the better strategy for materialists is to show that phenomenal-physical identity statements comprise a special class of statements to which Kripke’s general strategy does not apply. In this paper I contribute to this project by examining, and challenging, Stephen Yablo’s (2005) general objections to Kripke’s strategy, and sketch a principled way to draw a distinction between phenomenal-physical identity statements and other a posteriori modal claims.

Sober 2011 argues that, contrary to Hume, some causal statements can be known a priori to be true?notably, some ?would promote? statements figuring in causal models of natural selection. We find Sober's argument unconvincing. We regard the Humean thesis as denying that causal explanations contain any a priori knowable statements specifying certain features of events to be causally relevant. We argue that not every ?would promote? statement is genuinely causal, and we suggest that Sober has not shown that his examples of ?would promote? statements manage to achieve a priori status without sacrificing their causal character.

In Frege’s Puzzle, Nathan Salmon argues that his theory of singular propositions enables him to refute Saul Kripke’s claim that some identity statements are necessary and yet a posteriori. In this paper, through a critical examination of Salmon’s rejoinders to my earlier objections to his argument, I show what implications the theory of singular propositions has for the notion of apriority. I argue that Salmon’s handling of the ‘trivialization problem,’ which presents serious difficulties for his ‘absolute’ account of apriority, leaves a great deal to be desired. I suggest, in conclusion, that the theorist of singular propositions should hold a relative view of apriority.

[Robert Stalnaker] Saul Kripke made a convincing case that there are necessary truths that are knowable only a posteriori as well as contingent truths that are knowable a priori. A number of philosophers have used a two-dimensional model semantic apparatus to represent and clarify the phenomena that Kripke pointed to. According to this analysis, statements have truth-conditions in two different ways depending on whether one considers a possible world 'as actual' or 'as counterfactual' in determining the truth-value of the statement relative to that possible world. There are no necessary a posteriori or contingent a priori propositions: rather, contingent a priori and necessary a posteriori statements are statements that are necessary when evaluated one way, and contingent when evaluated the other way. This paper distinguishes two ways that the two-dimensional framework can be interpreted, and argues that one of them gives the better account of what it means to 'consider a world as actual', but that it provides no support for any notion of purely conceptual a priori truth. /// [Thomas Baldwin] Two-dimensional possible world semantic theory suggests that Kripke's examples of the necessary a posteriori and contingent a priori should be handled by interpreting names as implicitly indexical. Like Stalnaker, I reject this account of names and accept that Kripke's examples have to be accommodated within a metasemantic theory. But whereas Stalnaker maintains that a metasemantic approach undermines the conception of a priori truth, I argue that it offers the opportunity to develop a conception of the a priori aspect of stipulations, conceived as linguistic performances. The resulting position accommodates Kripke's examples in a way which is both intrinsically plausible and fits with Kripke's actual discussion of them.

[Robert Stalnaker] Saul Kripke made a convincing case that there are necessary truths that are knowable only a posteriori as well as contingent truths that are knowable a priori. A number of philosophers have used a two-dimensional model semantic apparatus to represent and clarify the phenomena that Kripke pointed to. According to this analysis, statements have truth-conditions in two different ways depending on whether one considers a possible world 'as actual' or 'as counterfactual' in determining the truth-value of the statement relative to that possible world. There are no necessary a posteriori or contingent a priori propositions: rather, contingent a priori and necessary a posteriori statements are statements that are necessary when evaluated one way, and contingent when evaluated the other way. This paper distinguishes two ways that the two-dimensional framework can be interpreted, and argues that one of them gives the better account of what it means to 'consider a world as actual', but that it provides no support for any notion of purely conceptual a priori truth. /// [Thomas Baldwin] Two-dimensional possible world semantic theory suggests that Kripke's examples of the necessary a posteriori and contingent a priori should be handled by interpreting names as implicitly indexical. Like Stalnaker, I reject this account of names and accept that Kripke's examples have to be accommodated within a metasemantic theory. But whereas Stalnaker maintains that a metasemantic approach undermines the conception of a priori truth, I argue that it offers the opportunity to develop a conception of the a priori aspect of stipulations, conceived as linguistic performances. The resulting position accommodates Kripke's examples in a way which is both intrinsically plausible and fits with Kripke's actual discussion of them.

In Naming and Necessity Saul Kripke offers a number of arguments in order to show that no descriptivist theory of proper names is correct. We present here a certain version of descriptivist theory -we will characterize it as an individual-use reference-fixing descriptivist theory that appeals to descriptions regarding how a name is used by other speakers. This kind of theory can successfully answer all the objections Kripke puts forward in Naming and Necessity. Such sort of descriptivist theory is furthermore compatible with the picture about reference that Kripke presents. It also seems to be able to account for some phenomena that are difficult to explain on Kripke’s view (the existence of informative identity statements and true negative singular existential statements).

The classical view of the relationship between necessity and apriority, defended by Leibniz and Kant, is that all necessary truths are known a priori. The classical view is now almost universally rejected, ever since Saul Kripke and Hilary Putnam discovered that there are necessary truths that are known only a posteriori. However, in recent years a new debate has emerged over the epistemology of these necessary a posteriori truths. According to one view – call it the neo-classical view – knowledge of a necessary truth always depends on at least one item of a priori knowledge. According to the rival view – call it the neoempiricist view – our knowledge of necessity is sometimes broadly empirical. In this paper I present and defend an argument against the neo-empiricist view. I argue that knowledge of the necessity of a necessary truth could not be broadly empirical.

In Naming and Necessity' Saul A. Kripke gives two types of examples of contingent truths knowable a priori. So he disagrees with the first leg of the thesis. As we will see later, his examples depend on the direct designation theory of names. While there have been attempts to provide examples of the contingent a priori that do not depend on that theory, most of those examples should be viewed as expansions, or modifications, of Kripke's examples. Philip Kitcher, for example, gives an interesting example that has nothing to do with theories of names, but is produced using the indexical 'actual'.2 His example, however, is a variation of Kripke's Neptune Type example.' In what follows I will focus on Kripke's two types of examples and modifications of them. I will argue that although both types of example fail, it is possible to modify his Standard Metre example in such a way that we have an example of the contingent a priori.

The thesis that the necessary and the a priori are extensionally equivalent consists of two independent claims: 1) All a priori truths are necessary and 2) all necessary truths are a priori. In Naming and Necessity1 Saul A. Kripke gives examples of necessary but a posteriori truths, so he disagrees with the second leg of the thesis.2 His examples are of two types; on the one hand statements involving essential properties and on the other hand true identity statements. My concern will be with examples of the second type and whether they refute (2). (2), however, is ambiguous and can mean one of three things: a) If p is a necessary truth, then one can know a priori that p is necessary. b) If p is a necessary truth, then one can know a priori that p. c) If p is a necessary truth, then one can know a priori that p and that p is necessary. Kripke maintains that we know a priori that if an identity statement is true, then it is necessarily true. Consequently, the issue at hand is how we come to know the truth of such identity statements, so it is clearly (b) that we should be concerned with.3 In order to refute (b), and thus (2), we apparently need to show that..