Jacob Joshua Ross

The phenomenon of disagreement has recently been brought into focus by the debate between contextualists and relativist invariantists about epistemic expressions such as ‘might’, ‘probably’, indicative conditionals, and the deontic ‘ought’. Against the orthodox contextualist view, it has been argued that an invariantist account can better explain apparent disagreements across contexts by appeal to the incompatibility of the propositions expressed in those contexts. This paper introduces an important and underappreciated phenomenon associated with epistemic expressions — a phenomenon that we call reversibility. We argue that the invariantist account of disagreement is incompatible with reversibility, and we go on to show that reversible sentences cast doubt on the putative data about disagreement, even without assuming invariantism. Our argument therefore undermines much of the motivation for invariantism, and provides a new source for constraints on the proper explanation of purported data about disagreement

This paper compares two alternative explanations of pragmatic encroachment on knowledge (i.e., the claim that whether an agent knows that p can depend on pragmatic factors). After reviewing the evidence for such pragmatic encroachment, we ask how it is best explained, assuming it obtains. Several authors have recently argued that the best explanation is provided by a particular account of belief, which we call pragmatic credal reductivism. On this view, what it is for an agent to believe a proposition is for her credence in this proposition to be above a certain threshold, a threshold that varies depending on pragmatic factors. We show that while this account of belief can provide an elegant explanation of pragmatic encroachment on knowledge, it is not alone in doing so, for an alternative account of belief, which we call the reasoning disposition account, can do so as well. And the latter account, we argue, is far more plausible than pragmatic credal reductivism, since it accords far better with a number of claims about belief that are very hard to deny

This paper defends the claim that there is a deep tension between the principle of countable additivity and the one-third solution to the Sleeping Beauty problem. The claim that such a tension exists has recently been challenged by Brian Weatherson, who has attempted to provide a countable additivity-friendly argument for the one-third solution. This attempt is shown to be unsuccessful. And it is argued that the failure of this attempt sheds light on the status of the principle of indifference that underlies the tension between countable additivity and the one-third solution.

Currently, the most popular views about how to update de se or self-locating beliefs entail the one-third solution to the Sleeping Beauty problem.2 Another widely held view is that an agent‘s credences should be countably additive.3 In what follows, I will argue that there is a deep tension between these two positions. For the assumptions that underlie the one-third solution to the Sleeping Beauty problem entail a more general principle, which I call the Generalized Thirder Principle, and there are situations in which the latter principle and the principle of Countable Additivity cannot be jointly satisfied. The most plausible response to this tension, I argue, is to accept both of these principles, and to maintain that when an agent cannot satisfy them both, she is faced with a rational dilemma.

Currently, it appears that the most widely accepted solution to the Sleeping Beauty problem is the one-third solution. Another widely held view is that an agent’s credences should be countably additive. In what follows, I will argue that these two views are incompatible, since the principles that underlie the one-third solution are inconsistent with the principle of Countable Additivity (hereafter, CA). I will then argue that this incompatibility is a serious problems for thirders, since it undermines one of the central arguments for their position.

Is rationality normative, in the sense that we ought to be rational, in our actions and attitudes? Recently, the claim that rationality is normative has faced several challenges. In this paper, I will take up these challenges, and aim to vindicate the normativity of rationality in the face of them. I will begin, in part 1, by outlining these challenges, and then discussing, and criticizing, some that have been offered to them in the literature. Then, in part 2, I will offer my own, unified response to these challenges

Originally published in 1970. This work evaluates the appeal to the sensually given which played an important role in epistemological discussions during the early 20 th Century. While many contemporary philosophers regarded this appeal as a mistake, there were still some who defended the notion of the given and even made it the foundation of their views regarding perception. The author here points to several different views concerning the nature of the sensually given and argues that the issue between them is not empirical, as is naturally suggested by what he calls ‘the Naïve View’ of the dispute, but rather metaphysical, involving different theories regarding the relationship between Thought and Reality. This leads on to a discussion of the different views presently held regarding the task of the epistemologist, and to a new suggestion with regard to the relationship between common sense and the rival ontologies suggested by scientists and philosophers. In the course of the argument a variety of different topics are discussed such as the correspondence and coherence theories of truth, the differences between scientific and philosophical theories, and the relevance of scientific treatments of the subject of perception to the treatment of this topic by philosophers

By all indications, the popularity of the Sense-Datum Theory is definitely on the wane. This once-proud theory, which was perhaps the most characteristic feature of British Philosophy during the first half of this century, has been attacked from so many different sides that even its foremost protagonists have either accepted the very watered-down version according to which it is just an alternative language for speaking about the facts of perception or else they hold their peace and let the youngsters play. There are still some diehards who carry on as if nothing had happened, but they are an insignificant minority

This paper is concerned with a recent argument of Jerry Fodor's to the effect that the frame problem in artificial intelligence is in principle insoluble. Fodor's argument is based on his contention that the mind is divided between encapsulated modular systems for information processing and 'central systems' for non-demonstrative inference. I argue that positing central systems is methodologically unsound, and in fact involves a muddle that bears a strong family resemblance to the basic error in dualism. I therefore conclude that Fodor's position on the frame problem should be rejected

In everyday arguments we often meet with such phrases as ‘That's rational, it is mere common sense’ used in conjunction to approve of or back up some particular statement. The juxtaposition of these everyday locutions embodies a profound truth, the truth, namely, that the basis of rational communication between human beings is plain common sense. I call this point profound because it has been missed in all the discussions about rationality and its basis that I know; certainly its elusiveness thus seems to indicate that participants in these discussions have not delved deeply enough. But I concede that this truth is simple and obvious, and conclude, therefore, that it has been overlooked only because its very obviousness has been taken, wrongly, to indicate superficiality and inadequacy. In suggesting that it is neither superficial nor inadequate I shall be relying on Wittgenstein's interpretation of Moore's ‘Defence of Common Sense’, to which I shall be adding a particular twist of my own.