Traditional definitions of common ground in terms of iterative de re attitudes do not apply to conversations where at least one conversational participant is not acquainted with the other(s). I propose and compare two potential refinements of traditional definitions based on Abelard’s distinction between generality in sensu composito and in sensu diviso.

Esta enciclopédia abrange, de uma forma introdutória mas desejavelmente rigorosa, uma diversidade de conceitos, temas, problemas, argumentos e teorias localizados numa área relativamente recente de estudos, os quais tem sido habitual qualificar como «estudos lógico-filosóficos». De uma forma apropriadamente genérica, e apesar de o território teórico abrangido ser extenso e de contornos por vezes difusos, podemos dizer que na área se investiga um conjunto de questões fundamentais acerca da natureza da linguagem, da mente, da cognição e do raciocínio humanos, bem (...) como questões acerca das conexões destes com a realidade não mental e extralinguística. A razão daquela qualificação é a seguinte: por um lado, a investigação em questão é qualificada como filosófica em virtude do elevado grau de generalidade e abstracção das questões examinadas (entre outras coisas); por outro, a investigação é qualificada como lógica em virtude de ser uma investigação logicamente disciplinada, no sentido de nela se fazer um uso intenso de conceitos, técnicas e métodos provenientes da disciplina de lógica. O agregado de tópicos que constitui a área de estudos lógico-filosóficos é já visível, pelo menos em parte, no Tractatus Logico-Philosophicus de Ludwig Wittgenstein, uma obra publicada em 1921. E uma boa maneira de ter uma ideia sinóptica do território disciplinar abrangido por esta enciclopédia, ou pelo menos de uma porção substancial dele, é extrair do Tractatus uma lista dos tópicos mais salientes aí discutidos; a lista incluirá certamente tópicos do seguinte género, muitos dos quais se podem encontrar ao longo desta enciclopédia: factos e estados de coisas; objectos; representação; crenças e estados mentais; pensamentos; a proposição; nomes próprios; valores de verdade e bivalência; quantificação; funções de verdade; verdade lógica; identidade; tautologia; o raciocínio matemático; a natureza da inferência; o cepticismo e o solipsismo; a indução; as constantes lógicas; a negação; a forma lógica; as leis da ciência; o número. (shrink)

This book combines insights from philosophy and linguistics to develop a novel framework for theorizing about linguistic meaning and the role of context in interpretation. A key innovation is to introduce explicit representations of context — assignment variables — in the syntax and semantics of natural language. The proposed theory systematizes a spectrum of “shifting” phenomena in which the context relevant for interpreting certain expressions depends on features of the linguistic environment. Central applications include local and nonlocal contextual dependencies with (...) quantifiers, attitude ascriptions, conditionals, questions, and relativization. The result is an innovative, philosophically informed compositional semantics compatible with the truth-conditional paradigm. (shrink)

What does it mean to know how to do something? This book develops a comprehensive account of know-how, a crucial epistemic goal for all who care about getting things right, not only with respect to the facts, but also with respect to practice. It proposes a novel interpretation of the seminal work of Gilbert Ryle, according to which know-how is a competence, a complex ability to do well in an activity in virtue of guidance by an understanding of what it (...) takes to do so. This idea is developed into a full-fledged account, Rylean responsibilism, which understands know-how in terms of the normative guidance and responsible control of one's acts. Within the complex current debate about know-how, this view occupies a middle ground position between the intellectualist claim that know-how just is propositional or objectual knowledge and the anti-intellectualist claim that know-how just is ability. In genuine know-how, practical ability and guiding intellect are both necessary, but essentially intertwined. (shrink)

Does the self exist? If so, what is its nature? How long do selves last? Galen Strawson draws on literature and psychology as well as philosophy to discuss various ways we experience having or being a self. He argues that it is legitimate to say that there is such a thing as the self, distinct from the human being.

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)

The paper has two parts: First, I describe a relatively popular thesis in the philosophy of propositional attitudes, worthy of the name ‘taking tense seriously’; and I distinguish it from a family of views in the metaphysics of time, namely, the A-theories (or what are sometimes called ‘tensed theories of time’). Once the distinction is in focus, a skeptical worry arises. Some A-theorists maintain that the difference between past, present, and future, is to be drawn in terms of what exists: (...) growing-block theorists eschew ontological commitment to future entities; presentists, to future and past entities. Others think of themselves as A-theorists but exclude no past or future things from their ontology. The metaphysical skeptic suspects that their attempt to articulate an ‘eternalist’ version of the A-theory collapses into merely ‘taking tense seriously’– a thesis that does not imply the A-theory. The second half of the paper is the search for a stable eternalist A-theory. It includes discussion of temporary intrinsics, temporal parts, and truth. (shrink)

This paper is about the semantic analysis of referentially opaque verbs like seek and owe that give rise to nonspecific readings. It is argued that Montague's categorization (based on earlier work by Quine) of opaque verbs as properties of quantifiers runs into two serious difficulties: the first problem is that it does not work with opaque verbs like resemble that resist any lexical decomposition of the seek ap try to find kind; the second one is that it wrongly predicts de (...) dicto (i.e. narrow scope) readings due to quantified noun phrases in the object positions of such verbs. It is shown that both difficulties can be overcome by an analysis of opaque verbs as operating on properties. This is a strongly modified version of a paper entitled lsquoDo We Bear Attitudes towards Quantifiers?rsquo that I have presented at conferences in Gosen (Gesellschaft für Sprachwissenschaft), Ithaca (SALT I), and Konstanz (Lexikon). I owe a special debt to Hans Kamp and Arnim von Stechow for shaping my views on the subject of this paper during the past ten years or so. Comments from and discussions with the following friends and colleagues have also led to considerable improvements: Heinrich Beck, Steve Berman, David Dowty, Veerle van Geenhoven, Fritz Hamm, Irene Heim, Wolfgang Klein, Angelika Kratzer, Michael Morreau, Barbara Partee, Mats Rooth, Roger Schwarzschild, Wolfgang Sternefeld, Emil Weydert, Henk Zeevat, and three referees. (shrink)

The paper is about the interpretation of opaque verbs like “seek”, “owe”, and “resemble” which allow for unspecific readings of their (indefinite) objects. It is shown that the following two observations create a problem for semantic analysis: (a) The opaque position is upward monotone: “John seeks a unicorn” implies “John seeks an animal”, given that “unicorn” is more specific than “animal”. (b) Indefinite objects of opaque verbs allow for higher-order, or “underspecific”, readings: “Jones is looking for something Smith is looking (...) for” can express that there is something unspecific that both Jones and Smith are looking for. Given (a) and (b), it would seem that the following inference is hard to escape, if the premisses are construed unspecifically and the conclusion is taken on its under- specific reading: Jones is looking for a sweater. Smith is looking for a pen. Smith is looking for something Jones is looking for. (shrink)

This paper offers an explanation of the fact that sentences of the form (1) ‘X may A or B’ may be construed as implying (2) ‘X may A and X may B’, especially if they are used to grant permission. It is suggested that the effect arises because disjunctions are conjunctive lists of epistemic possibilities. Consequently, if the modal may is itself epistemic, (1) comes out as equivalent to (2), due to general laws of epistemic logic. On the other hand, (...) on a deontic reading of may, (2) is only implied under exceptional circumstances – which usually obtain when (1) is used performatively. (shrink)

Recent years have brought relativistic accounts of knowledge, first-person belief, and future contingents to prominence. I discuss these views, distinguish non-trivial from trivial forms of relativism, and then argue against relativism in all of its substantive varieties.

Focusing on predicates of taste, this paper puts forward a novel version of relativism, motivated by a recently discussed phenomenon: perspectival plurality. After showing that the phenomenon is problematic for at least some versions of relativism and discussing several possible answers on behalf of the relativist, I put forward my own version. The main feature of the proposal is the introduction in the index not of a single parameter for perspectives, but of a (possibly infinite) sequence of such parameters. In (...) the last part of the paper, I defend the view from three objections. (shrink)

In the debate about the nature and identity of possible worlds, philosophers have neglected the parallel questions about the nature and identity of moments of time. These are not questions about the structure of time in general, but rather about the internal structure of each individual time. Times and worlds share the following structural similarities: both are maximal with respect to propositions (at every world and time, either p or p is true, for every p); both are consistent; both are (...) closed (every modal consequence of a proposition true at a world is also true at that world, and every tense-theoretic consequence of a proposition true at a time is also true at that time); just as there is a unique actual world, there is a unique present moment; and just as a proposition is necessarily true iff true at all worlds, a proposition is eternally true iff true at all times. In this paper, I show that a simple extension of my theory of worlds yields a theory of times in which the above structural similarities between the two are consequences. (shrink)

Externalism is the thesis that the contents of intentional states and speech acts are not determined by the way the subjects of those states or acts are internally. It is a widely accepted but not entirely uncontroversial thesis. Among such theses in philosophy, externalism is notable for owing the assent it commands almost entirely to thought experiments, especially to variants of Hilary Putnam's famous Twin Earth scenario. This paper presents a thought experiment-free argument for externalism. It shows that externalism is (...) a deductive consequence of a pair of widely accepted principles whose relevance to the issue has hitherto gone unnoticed. (shrink)

As Quine observed, the following sentence has a reading which, if true, would be of special interest to the authorities: Ralph believes that someone is a spy. This is the reading where the quantifier is naturally understood as taking wide scope relative to the attitude verb and as binding a variable within the scope of the attitude verb. This essay is interested in addressing the question what the semantic analysis of this kind of reading should look like from a Fregean (...) perspective—a perspective according to which attitude states are generally relations to structured Fregean thoughts composed of senses. The Fregean view faces a challenge of compositionality here. This essay describes the challenge and offers a response on the Fregean's behalf. (shrink)

Epistemic modal operators give rise to something very like, but also very unlike, Moore's paradox. I set out the puzzling phenomena, explain why a standard relational semantics for these operators cannot handle them, and recommend an alternative semantics. A pragmatics appropriate to the semantics is developed and interactions between the semantics, the pragmatics, and the definition of consequence are investigated. The semantics is then extended to probability operators. Some problems and prospects for probabilistic representations of content and context are explored.

Those who object to David Lewis' modal realism express qualms about philosophical respectability of the Lewisian notion of a possible world and its correlate notion of an inhabitant of a possible world. The resulting impression is that these two notions either stand together or fall together. I argue that the Lewisian notion of a possible world is otiose even for a good Lewisian modal realist, and that one can carry out a good Lewisian semantics for modal discourse without Lewisian possible (...) worls. I do so by generalizing Lewis' own idea that restrictions on quantification come and go with the pragmatic wind and relativizing possible worlds as shifting domains of discourse. I then suggest a way to soften the infamous incredulous stare. (shrink)

Predicates of personal taste have attracted a great deal of attention from philosophers of language and linguists. In the intricate debates over PPT, arguably the most central consideration has been which analysis of PPT can best account for the possibility of faultless disagreement about matters of personal taste. I argue that two models of such disagreement—the relativist and absolutist models—are empirically inadequate. In their stead, I develop a model of faultless taste disagreement which represents it as involving a novel incompatibility (...) relation between preferences that I call type-noncotenability. This model is available to all parties in the ongoing debates about PPT, but it points up an advantage enjoyed by expressivist accounts of PPT. In closing, I consider four objections against the model that, while failing to fully undermine it, open up promising avenues of inquiry about the nature of disagreement. (shrink)

Self-consciousness in non-human animals is a complex phenomenon which raises both conceptual and methodological problems. First, what do we mean by the concept of ‘self-consciousness’? Secondly, what is the best experimental approach to self-consciousness? This paper gives a short overview of the concept of self-consciousness in section 1. We can understand the concept of self-consciousness as capturing the ability of subjects to consciously think about themselves as themselves. If this is accurate, then it is prudent to look at a broad (...) bundle of abilities which are related to this ability. The paper then focuses on advantages and problems of the multipronged approach, a kind of empirical approach which uses several different test criteria to determine whether a subject is self-conscious or not. Section 2 briefly contrasts this kind of approach with other possibilities. The main disparity is to singlepronged approaches, which have been discussed and dismissed in greater detail elsewhere. Section 3 discusses the advantages of a multipronged approach, whereas section 4 is dedicated to the discussion of some of its problems. (shrink)

De se beliefs typically pose a problem for propositional theories of content. The Property Theory of content tries to overcome the problem of de se beliefs by taking properties to be the objects of our beliefs. I argue that the concept of self-ascription plays a crucial role in the Property Theory while being virtually unexplained. I then offer different possibilities of illuminating that concept and argue that the most common ones are either circular, question-begging, or epistemically problematic. Finally, I argue (...) that only a primitive understanding of self-ascription is viable. Self-ascription is the relation that subjects stand in with respect to the properties that they believe themselves to have. As such, self-ascription has to be primitive if it is supposed to do justice to the characteristic features of de se beliefs. (shrink)

This paper argues that the classification of propositional attitudes into the de re, de dicto, and de se is incomplete. De se attitudes are widely agreed to be closely connected to de re attitudes. But there is a species of belief that is linked to agent-centered action in the way that de se beliefs are, but is also associated with entities, places, and especially times, under a description. These mark out a fourth kind. One way to think about what makes (...) them distinctive is that, despite being ‘essentially indexical’ they can be retained across different contexts of evaluation without having diagonal content. The paper also discusses the connection between such beliefs and the kinds of utterances (like ‘Don't put off for tomorrow what you can do today’) that are contested as examples of what David Kaplan called ‘monsters.’. (shrink)

Simon Saunders and David Wallace have proposed an attractive semantics for interpreting linguistic communities embedded in an Everettian multiverse. It provides a charitable interpretation of our ordinary talk about the future, and allows us to retain a principle of bivalence for propositions and to retain the law of excluded middle in the logic of propositions about the future. But difficulties arise when it comes to providing an appropriate account of the metaphysics of macroscopic objects and events. I evaluate various metaphysical (...) frameworks which might be combined with the Saunders–Wallace semantics. I conclude that the most appropriate metaphysics to underwrite the semantics renders Everettian quantum mechanics a theory of non-overlapping worlds. (shrink)

Metaphilosophy, Volume 53, Issue 2-3, Page 162-175, April 2022.

A theory of evidential probability is developed from two assumptions:(1) the evidential probability of a proposition is its probability conditional on the total evidence;(2) one's total evidence is one's total knowledge. Evidential probability is distinguished from both subjective and objective probability. Loss as well as gain of evidence is permitted. Evidential probability is embedded within epistemic logic by means of possible worlds semantics for modal logic; this allows a natural theory of higher-order probability to be developed. In particular, it is (...) emphasized that it is sometimes uncertain which propositions are part of one's total evidence; some surprising implications of this fact are drawn out. (shrink)

Suppose for reductio that I know a proposition of the form <p and I don’t know p>. Then by the factivity of knowledge and the distribution of knowledge over conjunction, I both know and do not know p ; which is impossible. Propositions of the form <p and I don’t know p> are therefore unknowable. Their particular kind of unknowability has been widely discussed and applied to such issues as the realism debate. It hasn’t been much applied to theories of (...) the nature of knowledge. That is what I’m going to do here. (shrink)

Metaphysically possible worlds have many uses. Epistemically possible worlds promise to be similarly useful, especially in connection with propositions and propositional attitudes. However, I argue that there is a serious threat to the natural accounts of epistemically possible worlds, from a version of Russell’s paradox. I contrast this threat with David Kaplan’s problem for metaphysical possible world semantics: Kaplan’s problem can be straightforwardly rebutted, the problems I raise cannot. I argue that although there may be coherent accounts of epistemically possible (...) worlds with fruitful applications, any such an account must fundamentally compromise the basic idea behind epistemic possibility. (shrink)

Some theories of personal identity allow some variation in what it takes for a person to survive from context to context; and sometimes this is determined by the desires of person-stages or the practices of communities.This leads to problems for decision making in contexts where what is chosen will affect personal identity.‘Temporal Phase Pluralism’ solves such problems by allowing that there can be a plurality of persons constituted by a sequence of person stages. This illuminates difficult decision making problems when (...) persons have to choose between different life-altering choices. (shrink)

The Snow White problem is introduced to demonstrate how learning something of which one could not have learnt the opposite (due to observer selection bias) can change an agent’s probability assignment. This helps us to analyse the Sleeping Beauty problem, which is deconstructed as a combinatorial engine and a subjective wrapper. The combinatorial engine of the problem is analogous to Bertrand’s boxes paradox and can be solved with standard probability theory. The subjective wrapper is clarified using the Snow White problem. (...) Sample spaces for all three problems are presented. The conclusion is that subjectivity plays no irreducible role in solving the Sleeping Beauty problem and that no reference to centered worlds is required to provide the answer. (shrink)

The Mystery Room problem is a close variant of the Mystery Bag scenario. It is argued here that dealing with this problem requires no revision of the Bayesian formalism, since there exists a solution to this problem in which indexicals or demonstratives play no essential role. The solution does require labels, which are internal to the probabilistic model. While there needs to be a connection between at least one label and one indexical or demonstrative, that connection is external to the (...) probabilistic model that is used to determine the relevant conditional probability; hence, it does not complicate the update procedure. (shrink)

Standard principles of rational decision assume that an option's utility is both comprehensive and accessible. These features constrain interpretations of an option's utility. This essay presents a way of understanding utility and laws of utility. It explains the relation between an option's utility and its outcome's utility and argues that an option's utility is relative to a specification of the option. Utility's relativity explains how a decision problem's framing affects an option's utility and its rationality even for an agent who (...) is cognitively perfect and lacks only empirical information. The essay rewrites standard laws of utility to accommodate relativization to propositions' specifications. The new laws are generalizations of the standard laws and yield them as special cases. (shrink)

Expected-utility theory advances representation theorems that do not take the risk an act generates as a consequence of the act. However, a principle of expected-utility maximization that explains the rationality of preferences among acts must, for normative accuracy, take the act’s risk as a consequence of the act if the agent cares about the risk. I defend this conclusion against the charge that taking an act’s consequences to comprehend all the agent cares about trivializes the principle of expected-utility maximization.

It is a widely held view in philosophy that propositions perform a plethora of different theoretical roles. Amongst other things, they are believed to be the semantic values of sentences in contexts, the objects of attitudes, the contents of illocutionary acts, and the referents of that-clauses. This assumption is often combined with the claim that propositions have their truth-values eternally. In this paper I aim to show that these two assumptions are incompatible: propositions cannot both fulfill the mentioned roles and (...) be eternally true or false. Following Kaplan and Lewis’s Operator Argument, I argue that compositional semantic values of sentences in contexts do not correspond to eternal propositions. Thus, either we regard the non-eternal entities that in fact realize the semantic role of propositions as also fulfilling the remaining propositional roles, or we abandon the assumption that there is a unique realizer of all the roles. The Operator Argument has recently come under attack, mainly for its tense-logical assumptions. However, rejecting these assumptions is not a sufficient defense of the compatibility of the two claims, since the extensional alternative to the tense-logical framework does not allow us to universally retain eternal propositions as compositional semantic values of sentences either. (shrink)

ABSTRACT This paper defends a controversial view about personal identity. It argues that it is possible to endorse both Phenomenalism and Materialism about persons. Phenomenalism is the view that personal identity is grounded in phenomenal consciousness. Materialism is the view that we are material objects. Many believe that the two views are incompatible. In this paper, I show that it is possible to accept both. I consider two objections against their combination—the argument from disembodiment and an important objection by Tim (...) Bayne. My responses are based on Kripke’s analysis of necessary a posteriori and contingent a priori statements. I make the case that both objections rest on different kinds of modal illusions. This strategy can be applied to other arguments, and the paper is intended to advocate a general approach to personal identity. (shrink)

Beliefs are commonly analyzed as binary relations between subjects and propositions. Perry and Lewis have shown that the standard account has difficulties in handling self-locating beliefs. Robert Stalnaker has recently put forward a version of the standard account that is supposed to overcome this problem. Stalnaker's motivation for defending the propositional account of belief is that it comes with a simple and powerful propositional model of communication. In this paper I argue that Stalnaker's proposal fails. The only way of upholding (...) the propositional account of belief is by abandoning the simple account of communication. (shrink)

According to an attractive account of belief, our beliefs have centered content. According to an attractive account of communication, we utter sentences to express our beliefs and share them with each other. However, the two accounts are in conflict. In this paper I explore the consequences of holding on to the claim that beliefs have centered content. If we do in fact express the centered content of our beliefs, the content of the belief the hearer acquires cannot in general be (...) identical to the content the speaker expresses. I sketch an alternative account of communication, the Recentering model, that accepts this consequence and explains how expressed and acquired content are related. (shrink)

In a recent article, Adam Elga outlines a strategy for “Defeating Dr Evil with Self-Locating Belief”. The strategy relies on an indifference principle that is not up to the task. In general, there are two things to dislike about indifference principles: adopting one normally means confusing risk for uncertainty, and they tend to lead to incoherent views in some ‘paradoxical’ situations. I argue that both kinds of objection can be levelled against Elga’s indifference principle. There are also some difficulties with (...) the concept of evidence that Elga uses, and these create further difficulties for the principle. (shrink)

The Sleeping Beauty puzzle provides a nice illustration of the approach to self-locating belief defended by Robert Stalnaker in Our Knowledge of the Internal World (Stalnaker, 2008), as well as a test of the utility of that method. The setup of the Sleeping Beauty puzzle is by now fairly familiar. On Sunday Sleeping Beauty is told the rules of the game, and a (known to be) fair coin is flipped. On Monday, Sleeping Beauty is woken, and then put back to (...) sleep. If, and only if, the coin landed tails, she is woken again on Tuesday after having her memory of the Monday awakening erased.1 On Wednesday she is woken again and the game ends. There are a few questions we can ask about Beauty’s attitudes as the game progresses. We’d like to know what her credence that the coin landed heads should be (a) Before she goes to sleep Sunday; (b) When she wakes on Monday; (c) When she wakes on Tuesday; and (d) When she wakes on Wednesday? Standard treatments of the Sleeping Beauty puzzle ignore (d), run together (b) and (c) into one (somewhat ill-formed) question, and then divide theorists into ‘halfers’ or ‘thirders’ depending on how they answer it. Following Stalnaker, I’m going to focus on (b) here, though I’ll have a little to say about (c) and (d) as well. I’ll be following orthodoxy in taking 1 2 to be the clear answer to (a), and in taking the correct answers to (b) and (c) to be independent of how the coin lands, though I’ll briefly question that assumption at the end. An answer to these four questions should respect two different kinds of constraints. The answer for day n should make sense ‘statically’. It should be a sensible answer to the question of what Beauty should do given what information she then has. And the answer should make sense ‘dynamically’. It should be a sensible answer to the question of how Beauty should have updated her credences from some earlier day, given rational credences on the earlier day. As has been fairly clear since the discussion of the problem in Elga (2000), Sleeping Beauty is puzzling because static and dynamic considerations appear to push in different directions.. (shrink)

Nick Bostrom argues that if we accept some plausible assumptions about how the future will unfold, we should believe we are probably not humans. The argument appeals crucially to an indifference principle whose precise content is a little unclear. I set out four possible interpretations of the principle, none of which can be used to support Bostrom’s argument. On the first two interpretations the principle is false, on the third it does not entail the conclusion, and on the fourth it (...) only entails the conclusion given an auxiliary hypothesis that we have no reason to believe. (shrink)

It is argued thatde dicto andde re beliefs are attitudes towards syntactically structured entities (sentences) in the head. In order to identify the content of ade dicto orde re belief, we must be able to match causal relations of belief states to natural language inferences. Such match-ups provide sufficient empirical justification for regarding those causal relations as syntactic transformations, that is, inferences. But only syntactically structured entities are capable of enjoying such inferential relations. Hence,de dicto andde re beliefs must be (...) syntactically structured. Given that beliefs are also brain states, it follows that they are sentences in the brain. The argument presented here is shown to be an improvement over similar arguments advanced by Harman and Fodor. (shrink)

It is argued thatde dicto andde re beliefs are attitudes towards syntactically structured entities (sentences) in the head. In order to identify the content of ade dicto orde re belief, we must be able to match causal relations of belief states to natural language inferences. Such match-ups provide sufficient empirical justification for regarding those causal relations as syntactic transformations, that is, inferences. But only syntactically structured entities are capable of enjoying such inferential relations. Hence,de dicto andde re beliefs must be (...) syntactically structured. Given that beliefs are also brain states, it follows that they are sentences in the brain. The argument presented here is shown to be an improvement over similar arguments advanced by Harman and Fodor. (shrink)

I consider exactly what is involved in a solution to the probability problem of the Everett interpretation, in the light of recent work on applying considerations from decision theory to that problem. I suggest an overall framework for understanding probability in a physical theory, and conclude that this framework, when applied to the Everett interpretation, yields the result that that interpretation satisfactorily solves the measurement problem. Introduction What is probability? 2.1 Objective probability and the Principal Principle 2.2 Three ways of (...) satisfying the functional definition 2.3 Cautious functionalism 2.4 Is the functional definition complete? The Everett interpretation and subjective uncertainty 3.1 Interpreting quantum mechanics 3.2 The need for subjective uncertainty 3.3 Saunders' argument for subjective uncertainty 3.4 Objections to Saunders' argument 3.5 Subjective uncertainty again: arguments from interpretative charity 3.6 Quantum weights and the functional definition of probability Rejecting subjective uncertainty 4.1 The fission program 4.2 Against the fission program Justifying the axioms of decision theory 5.1 The primitive status of the decision-theoretic axioms 5.2 Holistic scepticism 5.3 The role of an explanation of decision theory Conclusion. (shrink)

Recent developments in cosmology indicate that every history having a non-zero probability is realized in infinitely many distinct regions of spacetime. Thus, it appears that the universe contains infinitely many civilizations exactly like our own, as well as infinitely many civilizations that differ from our own in any way permitted by physical laws. We explore the implications of this conclusion for ethical theory and for the doomsday argument. In the infinite universe, we find that the doomsday argument applies only to (...) effects which change the average lifetime of all civilizations, and not those which affect our civilization alone. 1. Introduction2. Physics background2.1The number of possible histories is finite2.2The universe is infinite2.3Every possible history occurs an infinite number of times3. Frequency and probability4. Inflation contrasted4.1Modal realism4.2Actualism4.3Eternal recurrence5. Ethical implications6. Universal doomsday6.1Application to our civilization in particular6.2Universal vs. particular dooms6.3Practical applications7. Concluding remarks. (shrink)