When an agent undergoes fission, how should the beliefs of the fission results relate to the pre-fission beliefs? This question is important for the Everett interpretation of quantum mechanics, but it is of independent philosophical interest. Among other things, fission scenarios demonstrate that ‘self-locating’ information can affect the probability of uncentred propositions even if an agent has no essentially self-locating uncertainty. I present a general update rule for centred beliefs that gives sensible verdicts in cases of fission, without relying on (...) controversial metaphysical or linguistic assumptions. The rule is supported by the same considerations that support standard conditioning in the traditional framework of uncentred propositions. (shrink)

Can self-locating beliefs be relevant to non-self-locating claims? Traditional Bayesian modeling techniques have trouble answering this question because their updating rule fails when applied to situations involving contextsensitivity. This essay develops a fully general framework for modeling stories involving context-sensitive claims. The key innovations are a revised conditionalization rule and a principle relating models of the same story with different modeling languages. The essay then applies the modeling framework to the Sleeping Beauty Problem, showing that when Beauty awakens her degree (...) of belief in heads should be one-third. This demonstrates that it can be rational for an agent who gains only self-locating beliefs between two times to alter her degree of belief in a non-self-locating claim. (shrink)

In addition to being uncertain about what the world is like, one can also be uncertain about one’s own spatial or temporal location in the world. My aim is to pose a problem arising from the interaction between these two sorts of uncertainty, solve the problem, and draw two lessons from the solution.

How should we update de dicto beliefs in the face of de se evidence? The Sleeping Beauty problem divides philosophers into two camps, halfers and thirders. But there is some disagreement among halfers about how their position should generalize to other examples. A full generalization is not always given; one notable exception is the Halfer Rule, under which the agent updates her uncentered beliefs based on only the uncentered part of her evidence. In this brief article, I provide a simple (...) example for which the Halfer Rule prescribes credences that, I argue, cannot be reasonably held by anyone. In particular, these credences constitute an egregious violation of the Reflection Principle. I then discuss the consequences for halfing in general. (shrink)

“Double-halfers” think that throughout the Sleeping Beauty Problem, Beauty should keep her credence that a fair coin flip came up heads equal to 1/2. I introduce a new wrinkle to the problem that shows even double-halfers can't keep Beauty's credences equal to the objective chances for all coin-flip propositions. This leaves no way to deny that self-locating information generates an unexpected kind of inadmissible evidence.

In this dissertation I spell out, and make a case for, egocentric presentism, a view about what it is for a thing to be me. I argue that there are benefits associated with adopting this view. ;The chief benefit comes in the sphere of ethics. Many of us, when we think about what to do, feel a particular kind of ambivalence. On the one hand we are moved by an impartial concern for the greater good. We feel the force of (...) considerations of the form: 'all things considered, doing...will make things better overall'. On the other hand we are selfish. We feel the force of considerations of the form 'doing...will make things better for me.' And it appears as if these sorts of considerations often conflict. Often by doing what makes things better for me I do not make things better overall, and vice-versa. But egocentric presentism is capable of resolving this conflict. As an egocentric presentist I can think both that considerations of the greater good always count in favor my doing what's good for me, and that considerations of the greater good always count in favor of other people doing what's good for them. ;Another benefit comes in the sphere of metaphysics. As an egocentric presentist I can make sense of some otherwise perplexing puzzles about personal identity over time, by combining a non-reductionist view about who I will be, with Parfitian reductionism about personal identity over time and a lean physicalist ontology. (shrink)

The Sleeping Beauty Problem attracts so much attention because it connects to a wide variety of unresolved issues in formal epistemology, decision theory, and the philosophy of science. The problem raises unanswered questions concerning relative frequencies, objective chances, the relation between self-locating and non-self-locating information, the relation between self-location and updating, Dutch Books, accuracy arguments, memory loss, indifference principles, the existence of multiple universes, and many-worlds interpretations of quantum mechanics. After stating the problem, this article surveys its connections to all (...) of these areas. (shrink)

The Sleeping Beauty puzzle has dramatized the divisive question of how de se beliefs should be integrated into formal theories of rational belief change. In this paper, I look ahead to a related question: how should de se beliefs be integrated into formal theories of rational choice? I argue that standard decision theoretic frameworks fail in special cases of de se uncertainty, like Sleeping Beauty. The nature of the failure reveals that sometimes rational choices are determined independently of one’s credences (...) in the kinds of ‘narrow’ de se propositions that Sleepy Beauty has set in relief. Consequently, in addition to pinpointing a failure of standard decision theoretic frameworks, this result casts doubt on a large class of strategies for determining principles for the rationally updating de se beliefs in cases like Sleeping Beauty, and also calls into question the importance of making such a determination at all. (shrink)

Dr. Evil learns that a duplicate of Dr. Evil has been created. Upon learning this, how seriously should he take the hypothesis that he himself is that duplicate? I answer: very seriously. I defend a principle of indifference for self-locating belief which entails that after Dr. Evil learns that a duplicate has been created, he ought to have exactly the same degree of belief that he is Dr. Evil as that he is the duplicate. More generally, the principle shows that (...) there is a sharp distinction between ordinary skeptical hypotheses, and self-locating skeptical hypotheses. (shrink)

In the Sleeping Beauty problem, Beauty is uncertain whether the outcome of a certain coin toss was heads or tails. One argument suggests that her degree of belief in heads should be 1/3, while a second suggests that it should be 1/2. Prima facie, the argument for 1/2 appears to be stronger. I offer a diachronic Dutch Book argument in favor of 1/3. Even for those who are not routinely persuaded by diachronic Dutch Book arguments, this one has some important (...) morals. (shrink)

Hitchcock advances a diachronic Dutch Book argument (DDB) for a 1/3 answer to the Sleeping Beauty problem. Bradley and Leitgeb argue that Hitchcock’s DDB argument fails. We demonstrate the following: (a) Bradley and Leitgeb’s criticism of Hitchcock is unconvincing; (b) nonetheless, there are serious reasons to worry about the success of Hitchcock’s argument; (c) however, it is possible to construct a new DDB for 1/3 about which such worries cannot be raised.

This is about the metaphysics of the self and ethical egoism. It can serve as a preview for my manuscript-in-progress below.

On one view of time past, present and future things exist, but their being past, present or future does not consist in their standing in before‐ and after‐relations to other things. So, for example, the event of the signing of the Magna Carta is past, and its being so does not consist in, or reduce to, its coming before the events of 2010.In this paper I discuss arguments for and against this view and view in its near vicinity, perspectival realism. (...) I suggest that perspectival realism is a better view than tense realism. It shares the principal virtues, but not the principal vices, of tense realism. (shrink)

Caspar Hare makes an original and compelling case for "egocentric presentism," a view about the nature of first-person experience, about what happens when we see things from our own particular point of view. A natural thought about our first-person experience is that "all and only the things of which I am aware are present to me." Hare, however, goes one step further and claims, counterintuitively, that the thought should instead be that "all and only the things of which I am (...) aware are present." There is, in other words, something unique about me and the things of which I am aware. On Myself and Other, Less Important Subjects represents a new take on an old view, known as solipsism, which maintains that people's experiences give them grounds for believing that they have a special, distinguished place in the world--for example, believing that only they exist or that other people do not have conscious minds like their own. Few contemporary thinkers have taken solipsism seriously. But Hare maintains that the version of solipsism he argues for is in indeed defensible, and that it is uniquely capable of resolving some seemingly intractable philosophical problems--both in metaphysics and ethics--concerning personal identity over time, as well as the tension between self-interest and the greater good. This formidable and tightly argued defense of a seemingly absurd view is certain to provoke debate. (shrink)

Argues for the "thirder" solution to the Sleeping Beauty puzzle. The argument turns on an analogy with a variant case, in which a coin-toss on Monday night determines whether one's memories of Monday are permanently erased, or merely suspended in such a way that they will return some time after one wakes up on Tuesday.

In this paper I present a variant of the “Sleeping Beauty” case that shows that the “halfer” approach to the original Sleeping Beauty problem is incompatible with an extremely plausible principle pertaining to cases of disagreement. This principle says that, in “nonpermissive” contexts, the weight you give to a disputant’s view ought to be proportional to your estimation of the strength of the disputant’s epistemic position with respect to the disputed proposition. In requiring such proportionality, the principle denies the possibility (...) of what I will call “robustly perspectival” contexts. Given the plausibility and widespread acceptance of this principle, its incompatibility with the halfer approach to Sleeping Beauty gives us an apparently powerful new argument against the halfer position and for the alternative “thirder” view. But I am a halfer, not a thirder. So I go on to argue that despite the principle’s intuitive plausibility, there are good reasons for thinking that the case presented here does involve a robustly perspectival context and that the principle should be rejected. I suggest that the lesson that we should draw from this case is not that we should accept the thirder view, but rather that rationality can be perspectival in a robust way that many may find quite surprising. (shrink)