Online research in philosophy

This paper presents two different kinds a priori entitlements and argues that both are necessary to account for scientific knowledge. On the one hand, there are formal a priori entitlements whose existence is grounded in conditions on concept possession. On the other hand, there are material a priori entitlements that an agent accrues in virtue of practical reasoning. The discussion aims to reconcile the strengths of Christopher Peacocke’s and Michael Friedman’s recent work on the a priori, while overcoming the weaknesses of their respective proposals.

[Brian P. McLaughlin] In recent years, some philosophers have claimed that we can know a priori that certain external world skeptical hypotheses are false on the basis of a priori knowledge that we are in certain kinds of mental states, and a priori knowledge that those mental states are individuated by contingent environmental factors. Appealing to a distinction between weak and strong a priority, I argue that weakly a priori arguments of this sort would beg the question of whether the skeptical hypothesis under assessment is true, and that the prospect of a sound strongly a priori argument of this sort seems dim. \\\ [David Owens] Contemporary discussion of scepticism focuses on the possibility that most or all of our beliefs might be false. I argue that the hypothesis of massive falsity and the associated 'problem of the external world' are inessential to the scepticisms of Descartes and Hume. What drives Cartesian and Humean scepticism is the demand for certainty: any possibility of error, however local, must be ruled out before we can claim either justified belief or knowledge. Contemporary philosophers have ignored this form of scepticism because they doubt that the demand for certainty can be motivated. But Descartes provides a sound motivation for this demand in the Meditations.

[Brian P. McLaughlin] In recent years, some philosophers have claimed that we can know a priori that certain external world skeptical hypotheses are false on the basis of a priori knowledge that we are in certain kinds of mental states, and a priori knowledge that those mental states are individuated by contingent environmental factors. Appealing to a distinction between weak and strong a priority, I argue that weakly a priori arguments of this sort would beg the question of whether the skeptical hypothesis under assessment is true, and that the prospect of a sound strongly a priori argument of this sort seems dim. \\\ [David Owens] Contemporary discussion of scepticism focuses on the possibility that most or all of our beliefs might be false. I argue that the hypothesis of massive falsity and the associated 'problem of the external world' are inessential to the scepticisms of Descartes and Hume. What drives Cartesian and Humean scepticism is the demand for certainty: any possibility of error, however local, must be ruled out before we can claim either justified belief or knowledge. Contemporary philosophers have ignored this form of scepticism because they doubt that the demand for certainty can be motivated. But Descartes provides a sound motivation for this demand in the Meditations.

Infallibilism about a priori justification is the thesis that for an agent A to be a priori justified in believing p, that which justifies A's belief that p must guarantee the truth of p. No analogous thesis is thought to obtain for empirically justified beliefs. The aim of this article is to argue that infallibilism about the a priori is an untenable philosophical position and to provide theoretical understanding why we not only can be, but rather must be, a priori justified in believing some false propositions. The argument develops notions of obviousness and conceptual understanding as a means of affording insight into the conditions for having a priori justification and, consequently, into why infallibilism cannot stand.

Infallibilism about a priori justification is the thesis that for an agent A to be a priori justified in believing p, that which justifies A's belief that p must guarantee the truth of p. No analogous thesis is thought to obtain for empirically justified beliefs. The aim of this article is to argue that infallibilism about the a priori is an untenable philosophical position and to provide theoretical understanding why we not only can be, but rather must be, a priori justified in believing some false propositions. The argument develops notions of obviousness and conceptual understanding as a means of affording insight into the conditions for having a priori justification and, consequently, into why infallibilism cannot stand.

[Brian P. McLaughlin] In recent years, some philosophers have claimed that we can know a priori that certain external world skeptical hypotheses are false on the basis of a priori knowledge that we are in certain kinds of mental states, and a priori knowledge that those mental states are individuated by contingent environmental factors. Appealing to a distinction between weak and strong a priority, I argue that weakly a priori arguments of this sort would beg the question of whether the skeptical hypothesis under assessment is true, and that the prospect of a sound strongly a priori argument of this sort seems dim. \\\ [David Owens] Contemporary discussion of scepticism focuses on the possibility that most or all of our beliefs might be false. I argue that the hypothesis of massive falsity and the associated 'problem of the external world' are inessential to the scepticisms of Descartes and Hume. What drives Cartesian and Humean scepticism is the demand for certainty: any possibility of error, however local, must be ruled out before we can claim either justified belief or knowledge. Contemporary philosophers have ignored this form of scepticism because they doubt that the demand for certainty can be motivated. But Descartes provides a sound motivation for this demand in the Meditations.

Many philosophers ponder the question of the a priori status of logical rules like modus ponens. In this paper I argue that the way in which such questions are usually posed is misguided. I argue that to accept modus ponens is nothing else than to have an implication; hence that to ask how do we know that implication obeys modus ponens does not make sense. To ask whether modus ponens is a priori is to ask whether having implication is a priori. I argue that as one is not born with a language (but perhaps only with a predisposition to acquire a certain kind of language, namely one posessing logical vocabulary and hence displaying logical structure), logical rules can be a priori only in the sense that we tend to acquire language governed by such rules.

Kant''s claim that the justification of transcendental philosophy is a priori is puzzling because it should be consistent with (1) his general restriction on the justification of knowledge, that intuitions must play a role in the justification of all nondegenerate knowledge, with (2) the implausibility of a priori intuitions being the only ones on which transcendental philosophy is founded, and with (3) his professed view that transcendental philosophy is not analytic. I argue that this puzzle can be solved, that according to Kant transcendental philosophy is justified a priori in the sense that the only empirical information required for its justification can be derived from any possible human experience. Transcendental justification does not rely on any more particular or special observations or experiments. Philip Kitcher''s general account of apriority in Kant captures this aspect of a priori knowledge. Nevertheless, I argue that Kitcher''s account goes wrong in the link it specifies between apriority and certainty.

In this paper I argue that a priori arguments fail to present any real problem for physicalism. They beg the question against physicalism in the sense that the argument will only seem compelling if one is already assuming that qualitative properties are nonphysical. To show this I will present the reverse-zombie and reverse-knowledge arguments. The only evidence against physicalism is a priori arguments, but there are also a priori arguments against dualism of exactly the same variety. Each of these parity arguments has premises that are just as intuitively plausible, and it cannot be the case that both the traditional scenarios and the reverse-scenarios are all ideally conceivable. Given this one set must be merely prima facie conceivable and only empirical methods will tell us which is which. So, by the time a priori methodology will be of any use it will be too late. <br>.

a priori. Since I ended up defending an unpopular answer to this question—"No"—it’s hardly surprising that people have scrutinized the account, or that many have concluded that I stacked the deck in the first place. Of course, this was not my view of the matter. My own judgment was that I’d uncovered the tacit commitments of mathematical apriorists and that the widespread acceptance of mathematical apriorism rested on failure to ask what was needed for knowledge to be a priori . Nevertheless, my critics have raised important challenges, and have offered rival conceptions that are less demanding. I want to examine their objections to my explication of a priori knowledge, and to explore whether the weaker alternatives succeed in preserving traditional philosophical claims. What follows is a mixture of penitence and intransigence.