Online research in philosophy

Merely conceptual knowledge, not based on specific sensitivity to the referential domain, is not seriously a priori. It is argued here that it is either weakly and superficially a priori, or downright a posteriori. This is done starting from the fact that many of our definitions (or concepts) are recognizably empirically established, and pointing out that recognizably empirical grounding yields superficial apriority. Further, some (first-order) concept analyzing propositions are empirically false about their referents and thus empirically refutable. Therefore, our empirical definitions (or concepts) are fallible and empirically revisable: they can turn out to be incorrect about the intended satisfiers of the concept defined, and their concept analyzing propositions to be false. Now, empirical revisability is incompatible with strong apriority (and entails at best a weak apriority or aposteriority). The result is quite shocking: analyticity does not entail apriority.

In an effort to account for our a priori knowledge of synthetic necessary truths, Kant proposes to extend the successful method used in mathematics and the natural sciences to metaphysics. In this paper, a uniform account of that method is proposed and the particular contribution of the ‘Copernican hypothesis’ to our knowledge of necessary truths is explained. It is argued that, though the necessity of the truths is in a way owing to the object's relation to our cognition, the truths we come to know are fully objective, expressing necessary relations between properties. Kant's distinction between ‘phenomena’ and ‘noumena’ is shown to serve to properly restrict the scope of the necessity claims so that they do express necessary connections between properties.

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.

Abstract : In this paper, it is argued that Leibniz’s view that necessity is grounded in the availability of a demonstration is incorrect and furthermore, can be shown to be so by using Leibniz’s own examples of infinite analyses. First, I show that modern mathematical logic makes clear that Leibniz’s "infinite analysis" view of contingency is incorrect. It is then argued that Leibniz's own examples of incommensurable lines and convergent series undermine, rather than bolster his view by providing examples of necessary mathematical truths that are not demonstrable. Finally, it is argued that a more modern view on convergent series would, in certain respects, help support some claims he makes about the necessity of mathematical truths, but would still not yield a viable theory of necessity due to remaining problems with other logical, mathematical, and modal claims.

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.

It is commonly accepted by Kant scholars that Kant held that all necessary truths are a priori, and all a priori knowledge is knowledge of necessary truths. Against the prevailing interpretation, I argue that Kant was agnostic as to whether necessity and a priority are co-extensive. I focus on three kinds of modality Kant implicitly distinguishes: formal possibility and necessity, empirical possibility and necessity, and noumenal possibility and necessity. Formal possibility is compatibility with the forms of experience; empirical possibility is compatibility with the causal powers of empirical objects; noumenal possibility is compatibility with the causal powers of things in themselves. Because we cannot know the causal powers of things in themselves, we cannot know what is noumenally necessary and what is noumenally contingent. Consequently, we cannot know whether noumenal necessity is co-extensive with a priority. Therefore, for all we know, some a priori propositions are noumenally contingent, and some a posteriori propositions are noumenally necessary. Thus, contrary to the received interpretation, Kant distinguishes epistemological from metaphysical modality.

I argue that you can have a priori knowledge of propositions that neither are nor appear necessarily true. You can know a priori contingent propositions that you recognize as such. This overturns a standard view in contemporary epistemology and the traditional view of the a priori, which restrict a priori knowledge to necessary truths, or at least to truths that appear necessary.

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..

Since Saul Kripke’s Naming and Necessity, the view that there are contingent apriori truths has been surprisingly widespread. In this paper, I argue against that view. My first point is that in general, occurrences of predicates “a priori” and “contingent” are implicitly relativized to some circumstance, involving an agent, a time, a location. My second point is that apriority and necessity coineide when relativized to the same circumstance. That is to say, what is known apriori (by an agent in a circumstance) cannot fail to be the case (in the same circumstance), hence it is necessary.

My target in this paper is a view that has sometimes been called the ‘Linguistic Doctrine of Necessary Truth’ (L-DONT) and sometimes ‘Conventionalism about Necessity’. It is the view that necessity is grounded in the meanings of our expressions—meanings which are sometimes identified with the conventions governing those expressions—and that our knowledge of that necessity is based on our knowledge of those meanings or conventions. In its simplest form the view states that a truth, if it is necessary, is necessary (and knowably necessary) because it is analytic. It is widely recognized that this simple version of the view faces a prima facie problem with the existence of the necessary a posteriori. Assuming that all analytic truths are a priori, if there are necessary a posteriori truths then there are necessary synthetic truths—contradicting the view’s claim that all necessary truths are analytic. Contemporary L-DONTers have things to say about the problem, but in this paper I want to suggest that there is a different, more serious, problem which arises from the phenomenon of indexicality, which L-DONTers have not taken account of. Though there are many versions of the problem, a simple one is this. Consider Kaplan’s celebrated sentence.