This is a wide-ranging 2004 book about arguments for and against beliefs in God. The arguments for the belief are analysed in the first six chapters and include ontological arguments from Anselm to Gödel, the cosmological arguments of Aquinas and Leibniz, and arguments from evidence for design and miracles. The next two chapters consider arguments against belief. The last chapter examines Pascalian arguments for and against belief in God. There are discussions of Cantorian problems for omniscience, of challenges to divine (...) omnipotence, and of the compatibility of everlasting complete knowledge of the world with free-will. There are appendices that present formal proofs in a system for quantified modal logic, a theory of possible worlds, notes on Cantorian set theory, and remarks concerning non-standard hyperreal numbers. This book will be a valuable resource for philosophers of religion and theologians and will interest logicians and mathematicians as well. (shrink)

J. Howard Sobel has long been recognized as an important figure in philosophical discussions of rational decision. He has done much to help formulate the concept of causal decision theory. In this volume of essays Sobel explores the Bayesian idea that rational actions maximize expected values, where an action's expected value is a weighted average of its agent's values for its possible total outcomes. Newcomb's Problem and The Prisoner's Dilemma are discussed, and Allais-type puzzles are viewed from the perspective of (...) causal world Bayesianism. The author establishes principles for distinguishing options in decision problems, and studies ways in which perfectly rational causal maximizers can be capable of resolute choices. Sobel also views critically Gauthier's revisionist ideas about maximizing rationality. This collection will be a desideratum for anyone working in the field of rational choice theory, whether in philosophy, economics, political science, psychology or statistics. Howard Sobel's work in decision theory is certainly among the most important, interesting and challenging that is being done by philosophers. (shrink)

A BAYESIAN ARTICULATION OF HUME’S VIEWS IS OFFERED BASED ON A FORM OF THE BAYES-LAPLACE THEOREM THAT IS SUPERFICIALLY LIKE A FORMULA OF CONDORCET’S. INFINITESIMAL PROBABILITIES ARE EMPLOYED FOR MIRACLES AGAINST WHICH THERE ARE ’PROOFS’ THAT ARE NOT OPPOSED BY ’PROOFS’. OBJECTIONS MADE BY RICHARD PRICE ARE DEALT WITH, AND RECENT EXPERIMENTS CONDUCTED BY AMOS TVERSKY AND DANIEL KAHNEMAN ARE CONSIDERED IN WHICH PERSONS TEND TO DISCOUNT PRIOR IMPROBABILITIES WHEN ASSESSING REPORTS OF WITNESSES.

Two partition-theorems are proved for a particular causal decision theory. One is restricted to a certain kind of partition of circumstances, and analyzes the utility of an option in terms of its utilities in conjunction with circumstances in this partition. The other analyzes an option's utility in terms of its utilities conditional on circumstances and is quite unrestricted. While the first form seems more useful for applications, the second form may be of theoretical importance in foundational exercises. Comparisons are made (...) with theorems of Richard Jeffrey, Brad Armendt, and Peter Fishburn. (shrink)

According to a familiar argument, iterated prisoner's dilemmas of known finite lengths resolve for ideally rational and well-informed players: They would defect in the last round, anticipate this in the next to last round and so defect in it, and so on. But would they anticipate defections even if they had been cooperating? Not necessarily, say recent critics. These critics "lose" the backward-induction paradox by imposing indicative interpretations on rationality and information conditions. To regain it I propose subjunctive interpretations. To (...) solve it I stress that implications for ordinary imperfect players are limited. (shrink)

To resolve putative liar paradoxes it is sufficient to attend to the distinction between liar-sentences and the propositions they would express, and to exercise the option of turning would-be deductions of paradox (of contradictions) into reductions of the existence of those propositions. Defending the coherence of particular resolutions along these lines, leads to recognition of the non-extensionality of some liar-sentences. In particular, it turns out that exchanges of terms for identicals in the open-sentence '- does not expression a true proposition' (...) are not invariably truth-preserving because they are not invariably proposition-expression preserving. All of this recommends propositions as fruitful subjects of interesting renewed research. (shrink)

Rational actions reflect beliefs and preferences in certain orderly ways. The problem of theory is to explain which beliefs and preferences are relevant to the rationality of particular actions, and exactly how they are relevant. One distinction of interest here is between an agent's beliefs and preferences just before an action's time, and his beliefs and preferences at its time. Theorists do not agree about the times of beliefs and desires that are relevant to the rationality of action. Another distinction (...) is between actions that would, in one sense or another, maximize expected utilities given relevant beliefs and desires, and actions, decisions for which would, in one sense or another, be stable. There is disagreement about the relevance of these things to the rationality of actions. Here, in the first part below, several possible positions on these issues are explained and compared. In the second part, I contrast perspectives on these issues, and comment on arguments that might be brought against the position I favor. In the third part, I restate and elaborate on this position. (shrink)

A person who does not have good intellectual reasons for believing in God can, depending on his probabilities and values for consequences of believing, have good practical reasons. Pascalian wagers founded on a variety of possible probability/value profiles are examined from a Bayesian perspective central to which is the idea that states and options are pragmatically reasonable only if they maximize subjective expected value. Attention is paid to problems posed by representations of values by Cantorian infinities. An appendix attends to (...) Robinsonian hyperreals. Another appendix presents for comparison Newcomb's Problem and a problem in some ways like it suggested, I think, by ideas of John Calvin. (shrink)

Moral properties would supervene upon non-moral properties and be conceptually autonomous. That, according to Simon Blackburn, would make them if not impossible at least mysterious, and evidence for them best explained by theorists who say they are not real. In fact moral properties would not challenge in ways Blackburn has contended. There is, however, something new that can be gathered from his arguments. What would the supervenience of moral properties and their conceptual autonomy from at least total non-moral properties entail (...) not only for Intuitionists, who ‘knew this all along,’ but for all moral realists, that there are synthetic necessary moral principles? There is for all moral realists the problem of explaining ‘what in the world’ makes possible these necessities. (shrink)

This paper is about David Gauthier’s concept of constrained maximization. Attending to his most detailed and careful account, I try to say how constrained maximization works, and how it might be changed to work better. In section I, that detailed account is quoted along with amplifying passages. Difficulties of interpretation are explained in section II. An articulation, a spelling out, of Gauthier's account is offered in section III to deal with these difficulties. Next, in section IV, constrained maximization thus articulated (...) is tested on several choice problems and shown to be seriously wanting. It appears that there are prisoners’ dilemmas in which constrained maximizers would not cooperate to mutual advantage, but would interact sub-optimally just as straight-maximizers would. ‘Coordination problems’ are described with which constrained maximizers might, especially if transparent to one another, not be able to cope–problems in which they might not be able to make up their minds to do anything at all. And I prove that there are prisoners’ dilemmas that, though possible for real agents and for straight maximizers, are not possible for constrained maximizers, so that agents’ internalising dispositions of constrained maximization could not be of help in connection with such possibly impending dilemmas. Taking constrained maximization as it stands, there are many problems for which it does not afford the ‘moral solutions’ with which Gauthier would have it replace Hobbesian political ones. After displaying these shortcomings of constrained maximization as presently designed, I sketch, in section V, possible revisions that would reduce them, stressing that these revisions would not be cost-free. Whether finishing the job of fixing up and making precise constrained maximization would be worth the considerable trouble it would involve lies beyond the issues taken up in this paper. So, of course, do substantive comparisons of constrained maximization, perfected and made precise, and straight maximization. (shrink)

It is plausible that Newcomb problems in which causal maximizers and evidential maximizers would do different things would not be possible for ideal maximizers who are attentive to metatickles. An objection to Eells’s first argument for this makes welcome a second. Against it I argue that even ideal evidential and causal maximizers would do different things in some non-dominance Newcomb problems; and that they would hope for different things in some third-person and non-action problems, which is relevant if a good (...) theory of rational choices of acts should fit smoothly into a good theory of rational desires for facts. (shrink)

David Gauthier stages a competition between two arguments, each of which purports to decide once for all transparent agents which is best, being a straight or being a constrained maximizer. The first argument, which he criticizes and rejects, is for the greater utility, on a certain weak assumption, of straight maximization for all transparent agents. The second, which he endorses, is for the greater utility on the same weak assumption of constrained maximization for all transparent agents.In Section I, Gauthier’s account (...) of constrained maximization is presented, and his use in the two arguments of the idea of choosing a disposition to choose actions is noted. Section II is about the unfortunate argument that Gauthier criticizes. This argument is flawed in ways additional to those he notices, but a less ambitious form of reasoning can, for individuals whose probabilities and values are right, be good for the greater expected utility of straight maximization. Section III takes up the argument that Gauthier endorses and maintains that it is wrong in a way specific to it as well as in ways closely related to all of the first argument’s noted flaws. An Appendix features a three-person prisoners’ dilemma and includes demonstrations of principal conclusions reached in the body of this paper. (shrink)

When causal decision theory was created in the 1970s, access to Howard Sobel’s contribution was available only in a narrowly circulated mimeographed manuscript. After some time, he allowed his ideas to appear in the form of articles. Here we finally have a book length exposition on Sobel’s causal Bayesian point of view consisting of collected, revised, and amplified papers spanning a period of twenty years.

The work is a charitable study on what the internationally renowned presenter and author, Howard Sobel, views to be largely the truth about moral thought and talk. Discussions and observations from David Humes own writings oftentimes reinforce and elaborate the authors notions and there is an assertive attempt to weave logical thinking into the book. Applications to such mathematical concepts as game theory, decision-making, and conditionals are dispersed throughout so as to enlighten the theory behind the ideas.

"It is a general maxim...’ That no testimony is sufficient to establish a miracle, unless the testimony be of such a kind that its falsehood would be more miraculous, than the fact which it endeavors to establish; and even in that case there is a mutual destruction of arguments, and the superior only gives us an assurance suitable to that degree of force, which remains, after deducting the inferior.’" A Bayesian interpretation of the first half is proved as a theorem. (...) A stronger conditional principle, and a biconditional theorem based on it, are substantiated. And a truth that the second part can express is explained. (shrink)

“To this day, partiality approaches to the paradox have been dogged by the so-called ‘Strengthened Liar’. .... The Strengthened Liar observes that if we follow a partiality theorist and declare the Liar sentence* neither true nor false (or failing to express a proposition,. or suffering from some sort of grave semantic defect), then the paradox is only pushed back. For we can go on to conclude that whatever this status may be, it implies that the Liar sentence is not true. (...) This claim is true, but it is just the Liar sentence again.* We are back in paradox.” (Glanzberg 2002, p. 468, bold emphasis added.) Cf.: “We are back in our contradiction,”(Glanzberg 2001, p. 222). *The Liar sentence intended is evidently the sentence ‘the Liar sentence is not true’, and, the Liar sentence = ‘the Liar sentence is not true’. Cf.: “Consider a Liar sentence: ...let us take a sentence l which says l is not true. We can, informally, reason as.. (shrink)

This response to critics includes elaboration of ideas and arguments in ’Logic and Theism’ regarding cumulative arguments for theism, probabilities, ’fine-tuning’ and many worlds, and Gödel’s ontological proof probabilities subjective and objective, and Mackiean doubts concerning the latter, are explained. There is discussion of ’dividing the evidence’ in Bayesian confirmation exercises, with some of it allowed to target ’priors’ of hypotheses, and there is a note on my problems with old evidence. Tentatively explored are Gödel’s considered modal opinions, which may (...) have included that every truth is necessary, and every falsehood impossible. (shrink)

Abstract: A Liar would express a proposition that is true and not true. A Liar Paradox would, per impossibile, demonstrate the reality of a Liar. To resolve a Liar Paradox it is sufficient to make out of its demonstration a reductio of the existence of the proposition that would be true and not true, and to "explain away" the charm of the paradoxical contrary demonstration. Persuasive demonstrations of the Liar Paradox in this paper trade on allusive scope-ambiguities of English definite (...) descriptions, and can seem confirmed by symbolizations in a Fregean theory in which scopes of definite descriptions are determinate. Symbolizing instead in a Russellian description theory in which alternative scopes are possible reveals that however the scope-ambiguities of the demonstration are settled the result is unsound. (shrink)

There are narrowest bounds for P(h) when P(e) = y and P(h/e) = x, which bounds collapse to x as y goes to 1. A theorem for these bounds -- bounds for probable modus ponens -- entails a principle for updating on possibly uncertain evidence subject to these bounds that is a generalization of the principle for updating by conditioning on certain evidence. This way of updating on possibly uncertain evidence is appropriate when updating by ’probability kinematics’ or ’Jeffrey-conditioning’ is, (...) and apparently in countless other cases as well. A more complicated theorem due to Karl Wagner -- bounds for probable modus tollens -- registers narrowest bounds for P(not h) when P(not e) = y and P(e/h) = x. This theorem serves another principle for updating on possibly uncertain evidence that might be termed ’contraditioning’, though it is for a way of updating that seems in practice to be frequently not appropriate. It is definitely not a way of putting down a theory -- for example, a random-chanc. (shrink)

Relations between conditional probabilities, revisions of probabilities in the light of new information, and conditions of ideal rationality are discussed herein. The formal character of conditional probabilities, and their significance for epistemic states of agents is taken up. Then principles are considered that would, under certain conditions, equate rationally revised probabilities on new information with probabilities reached by conditionalizing on this information. And lastly the possibility of kinds of ' books ' against known non-conditionalizers is explored, and the question is (...) taken up, What, if anything, would be wrong with a person against whom such a book could be made? (shrink)

Key words: liar paradoxes, propositions, definite descriptions A Liar would be a sentence or sentence-token that expresses a proposition that is both true and not true. A Liar Paradox is reasoning that would do the impossible and demonstrate the reality of a Liar. It is sufficient, fully to resolve a Liar Paradox, to turn its purported demonstration that some sentence or sentence-token expresses a proposition that is both true and not true into a reductio of the existence of the proposition (...) that would be expressed, while ‘explaining away’ the particular tricks and charm of the purported demonstration of paradox. The interest of these exercises lies in the seductiveness of the would be demonstration of a Liar Paradox, and in the depth and subtlety of logical/grammatical resources that can be tapped and fashioned to dispel it. The Liar taken on in this paper occasions especially seductive reasoning that exploits ‘scope-ambiguities’ of definite descriptions that, not incidentally, survive unscathed when its argument is symbolized in a Fregean description theory in which scopes of definite descriptions are not discriminated. Symbolizing this argument in a Russellian description theory in which scopes are discriminated makes unavoidable that its scope-ambiguities be settled one way or another, and reveals that however the scope ambiguity of a certain premise is settled the resultant unambiguous argument is unsound, either because it is invalid, though this premise comes out true, or because, though it is valid, this premise comes out not true. These results of Russellian analysis pave the way to a formal demonstration, from premises to which a monger of the paradox would be committed, that contrary to his case the Liar of this paper does not express a proposition. This conclusion is confirmed in the Appendix to this paper by a demonstration from a single empirical premise that no one can deny, in a Russellian calculus enhanced for truth of propositions expressed by tokens of sentences.. (shrink)

Moral properties would supervene upon non-moral properties and be conceptually autonomous. That, according to Simon Blackburn, would make them if not impossible at least mysterious, and evidence for them best explained by theorists who say they are not real. In fact moral properties would not challenge in ways Blackburn has contended. There is, however, something new that can be gathered from his arguments. What would the supervenience of moral properties and their conceptual autonomy from at least total non-moral properties entail (...) not only for Intuitionists, who `knew this all along,' but for all moral realists, that there are synthetic necessary moral principles? There is for all moral realists the problem of explaining `what in the world' makes possible these necessities. (shrink)

An example shows that 'pairwise preferences' (certain hypothetical choices) can cycle even when rational. General considerations entail that preferences tout court (certain relations of actual valuations) cannot cycle. A world-bayesian theory is explained that accommodates these two kinds of preference, and a theory for rational actions that would have them maximize and be objects of ratifiable choices. It is observed that choices can be unratifiable either because of troublesome credences or because of troublesome preferences. An appendix comments on a third (...) way in which efforts to maximize can be frustrated. (shrink)

I have maintained that some but not all prisoners' dilemmas are side-by-side Necomb problems. The present paper argues that, similarly, some but not all versions of Newcomb's Problem are prisoners' dilemmas in which Taking Two and Predicting Two make an equilibrium that is dispreferred by both the box-chooser and predictor to the outcome in which only one box is taken and this is predicted. I comment on what kinds of prisoner's dilemmas Newcomb's Problem can be, and on opportunities that results (...) reached may open for kinds of cooperative reasoning in versions of Newcomb's Problem. (shrink)

In his Truth and Probability (1926), Frank Ramsey provides foundations for measures of degrees of belief in propositions and preferences for worlds. Nonquantitative conditions on preferences for worlds, and gambles for worlds and certain near-worlds, are formulated which he says insure that a subject's preferences for worlds are represented by numbers, world values. Numbers, for his degrees of belief in propositions, probabilities, are then defined in terms of his world values. Ramsey does not also propose definitions of desirabilities for propositions, (...) though he is in a position to do this. Given his measures for probabilities of propositions and values of worlds, he can frame natural definitions for both evidential and causal desirabilities that would measure respectively the welcomeness of propositions as items of news, and as facts. His theory is neutral with respect to the evidential/causal division. In the present paper, as Ramsey's foundations are explained, several problems and limitations are noted. Their distinctive virtue – their evidential/causal neutrality – is demonstrated. Comparisons are made with other foundational schemes, and a perspective is recommended from which nonquantitative foundations are not the be all for quantitative theories of ideal preferences and credences. (shrink)

I take two passages in a recent paper by Kent Bach—‘Newcomb's Problem: The $1,000,000 Solution,’ Canadian Journal of Philosophy 17 409-25—as occasions for several observations about practical arguments and senses in which they may ‘work’ and be ‘good.’First Passage…one can only be amused by those advocates of BOTH who…realize that takers of BOTH almost always get but $1K whereas takers of ONE almost always get $1M, and proceed to bemoan the fact that rational people do so much worse than irrational (...) ones. Despite their logical scruples, they seem to have a curiously low standard of what constitutes a good argument. Evidently they would rather be right than rich. One would think that a solution requires not merely a seemingly irrefutable argument but an argument that works, one whose use is likely to pay off to the tune of at least $1M. (shrink)

I take two passages in a recent paper by Kent Bach—‘Newcomb's Problem: The $1,000,000 Solution,’ Canadian Journal of Philosophy 17 409-25—as occasions for several observations about practical arguments and senses in which they may ‘work’ and be ‘good.’First Passage…one can only be amused by those advocates of BOTH who…realize that takers of BOTH almost always get but $1K whereas takers of ONE almost always get $1M, and proceed to bemoan the fact that rational people do so much worse than irrational (...) ones. Despite their logical scruples, they seem to have a curiously low standard of what constitutes a good argument. Evidently they would rather be right than rich. One would think that a solution requires not merely a seemingly irrefutable argument but an argument that works, one whose use is likely to pay off to the tune of at least $1M. (shrink)