Online research in philosophy

In ‘A Non-Pragmatic Vindication of Probabilism’, Jim Joyce attempts to ‘depragmatize’ de Finetti’s prevision argument for the claim that our partial beliefs ought to satisfy the axioms of probability calculus. In this paper, I adapt Joyce’s argument to give a non-pragmatic vindication of various versions of David Lewis’ Principal Principle, such as the version based on Isaac Levi's account of admissibility, Michael Thau and Ned Hall's New Principle, and Jenann Ismael's Generalized Principal Principle. Joyce enumerates (...) properties that must be had by any measure of the distance from a set of partial beliefs to the set of truth values; he shows that, on any such measure, and for any set of partial beliefs that violates the probability axioms, there is a set that satisfies those axioms that is closer to every possible set of truth values. I replace truth values by objective chances in his argument; I show that for any set of partial beliefs that violates the probability axioms or a version of the Principal Principle, there is a set that satisfies them that is closer to every possible set of objective chances. (shrink)

Faced with the paradox of undermining futures, Humeans have resigned themselves to accounts of chance that severely conflict with our intuitions. However, such resignation is premature: The problem is Humean supervenience (HS), not Humeanism. This paper develops a projectivist Humeanism on which chance claims are understood as normative, rather than fact stating. Rationality constraints on the cotenability of norms and factual claims ground a factual-normative worlds semantics that, in addition to solving the Frege-Geach problem, delivers the intuitive set of possibilia (...) for each chance law. Hence, the account does not entail HS, and the paradox does not arise. A confirmation theory is developed, and the 'principal principle' is justified. (shrink)

This paper examines two mistakes regarding David Lewis’ Principal Principle that have appeared in the recent literature. These particular mistakes are worth looking at for several reasons: The thoughts that lead to these mistakes are natural ones, the principles that result from these mistakes are untenable, and these mistakes have led to significant misconceptions regarding the role of admissibility and time. After correcting these mistakes, the paper discusses the correct roles of time and admissibility. With these results in (...) hand, the paper concludes by showing that one way of formulating the chance–credence relation has a distinct advantage over its rivals. (shrink)

Any adequate theory of chance must accommodate some version of David Lewis's ‘Principal Principle’, and Lewis has argued forcibly that believers in primitive propensities have a problem in explaining what makes the Principle true. But Lewis can only derive (a revised version of) the Principle from his own Humean theory by putting constraints on inductive rationality which cannot be given a Humean rationale.

The experimental setup of the self-referential quantum measurement, jovially known as the ‘quantum suicide’ or the ‘quantum Russian roulette’ is analyzed from the point of view of the Principal Principle of David Lewis. It is shown that the apparent violation of this principle – relating objective probabilities and subjective chance – in this type of thought experiment is just an illusion due to the usage of some terms and concepts ill-defined in the quantum context. We conclude that (...) even in the case that Everett’s (or some other ‘no-collapse’) theory is a correct description of reality, we can coherently believe in equating subjective credence with objective chance in quantum-mechanical experiments. This is in agreement with results of the research on personal identity in the quantum context by Parfit and Tappenden. (shrink)

The experimental setup of the self-referential quantum measurement, jovially known as the "quantum suicide" or the "quantum Russian roulette" is analyzed from the point of view of the Principal Principle of David Lewis. It is shown that the apparent violation of this principle---relating objective probabilities and subjective chance---in this type of thought experiment is just an illusion due to the usage of some terms and concepts ill-defined in the quantum context. We conclude that even in the case (...) that Everett's (or some other "no-collapse") theory is a correct description of reality, we can coherently believe in equating subjective credence with objective chance in quantum-mechanical experiments. This is in agreement with results of the research on personal identity in the quantum context by Parfit and Tappenden. (shrink)

The Principal Principle (PP) says that, for any proposition A, given any admissible evidence and the proposition that the chance of A is x%, one's conditional credence in A should be x%. Humean Supervenience (HS) claims that, among possible worlds like ours, no two differ without differing in the spacetime-point-by-spacetime-point arrangement of local properties. David Lewis (1986b, 1994a) has argued that PP contradicts HS, and the validity of his argument has been endorsed by Bigelow et al. (1993), Thau (...) (1994), Hall (1994), Strevens (1995), Ismael (1996), Hoefer (1997), and Black (1998). Against this consensus, I argue that PP might not contradict HS: Lewis's argument is invalid, and every attempt -- within a broad class of attempts -- to amend the argument fails. (shrink)

Jim Joyce has presented an argument for Probabilism based on considerations of epistemic utility [Joyce, 1998]. In a recent paper, I adapted this argument to give an argument for Probablism and the Principal Principle based on similar considerations [Pettigrew, 2012]. Joyce’s argument assumes that a credence in a true proposition is better the closer it is to maximal credence, whilst a credence in a false proposition is better the closer it is to minimal credence. By contrast, my argument (...) in that paper assumed (roughly) that a credence in a proposition is better the closer it is to the objective chance of that proposition. In this paper, I present an epistemic utility argument for Probabilism and the Principal Principle that retains Joyce’s assumption rather than the alternative I endorsed in the earlier paper. I argue that this results in a superior argument for these norms. (shrink)

David Lewis (1980) proposed the Principal Principle (PP) and a “reformulation” which later on he called ‘OP’ (Old Principle). Reacting to his belief that these principles run into trouble, Lewis (1994) concluded that they should be replaced with the New Principle (NP). This conclusion left Lewis uneasy, because he thought that an inverse form of NP is “quite messy”, whereas an inverse form of OP, namely the simple and intuitive PP, is “the key to our concept (...) of chance”. I argue that, even if OP should be discarded, PP need not be. Moreover, far from being messy, an inverse form of NP is a simple and intuitive Conditional Principle (CP). Finally, both PP and CP are special cases of a General Principle (GP); it follows that so are PP and NP, which are thus compatible rather than competing. (shrink)

I show that David Lewis’s principal principle is not preserved under Jeffrey conditionalization. Using this observation, I argue that Lewis’s reason for rejecting the desire as belief thesis and Adams’s thesis applies also to his own principal principle. 1 Introduction2 Adams’s Thesis, the Desire as Belief Thesis, and the Principal Principle3 Jeffrey Conditionalization4 The Principal Principles Not Preserved under Jeffrey Conditionalization5 Inadmissible Experiences.

[1] You have a crystal ball. Unfortunately, it’s defective. Rather than predicting the future, it gives you the chances of future events. Is it then of any use? It certainly seems so. You may not know for sure whether the stock market will crash next week; but if you know for sure that it has an 80% chance of crashing, then you should be 80% confident that it will—and you should plan accordingly. More generally, given that the chance of a (...) proposition A is x%, your conditional credence in A should be x%. This is a chance-credence principle: a principle relating chance (objective probability) with credence (subjective probability, degree of belief). Let’s call it the Minimal Principle (MP). (shrink)

Organizational governance has historically focused around the perspective of principals and managers and has traditionally pursued the goal of maximizing owner wealth. This paper suggests that organizational governance can profitably be viewed from the ethical perspective of organizational followers - employees of the organization to whom important ethical duties are also owed. We present two perspectives of organizational governance: Principal Theory that suggests that organizational owners and managers can often be ethically opportunistic and take advantage of employees who serve (...) them and Principle Theory that focuses on guiding principles that are sometimes taken too far in organizations. In introducing these two new organizational governance perspectives, we offer insights into the value of rethinking ethical duties owed to organizational followers. (shrink)

A chance-credence norm states how an agent's credences in propositions concerning objective chances ought to relate to her credences in other propositions. The most famous such norm is the Principal Principle (PP), due to David Lewis. However, Lewis noticed that PP is inconsistent with many accounts of chance that attempt to reduce chance facts to non-modal facts. Those who defend such accounts of chance have offered two alternative chance-credence norms, both of which are consistent with reductionism about chance: (...) the first is the New Principle (NP), formulated by Ned Hall and Michael Thau and grudgingly accepted by Lewis; and the second is Jenann Ismael's General Recipe (IP). However, while NP and IP are each consistent with the sort of reductionism that conflicts with PP, they are incompatible with one another. Thus, the question arises: Which should the reductionist favour? In this paper, I argue that the consequences of IP when coupled with a reductionist account are unacceptable, so we must accept NP. I conclude by considering two responses to my arguments. (shrink)

In recent work, Callender and Cohen (2009) and Hoefer (2007) have proposed variants of the account of chance proposed by Lewis (1994). One of the ways in which these accounts diverge from Lewis’s is that they allow special sciences and the macroscopic realm to have chances that are autonomous from those of physics and the microscopic realm. A worry for these proposals is that autonomous chances may place incompatible constraints on rational belief. I’ll examine this worry, and attempt to determine (...) (i) what kinds of conflicts would be problematic, and (ii) whether these proposals lead to problematic conflicts. By working through a pair of cases, I’ll suggest that these proposals do give rise to problematic conflicts. (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.

David Lewis, Michael Thau, and Ned Hall have recently argued that the Principal Principle—an inferential rule underlying much of our reasoning about probability—is inadequate in certain respects, and that something called the ‘New Principle’ ought to take its place. This paper argues that the Principle Principal need not be discarded. On the contrary, Lewis et al. can get everything they need—including the New Principle—from the intuitions and inferential habits that inspire the Principal (...) class='Hi'>Principle itself, while avoiding the problems that originally caused them to abandon that principle. (shrink)

Rawls's difference principle contains a certain normative ambiguity, so that opposing views, including strong inegalitarian ones, might find a home under it. The element that introduces this indeterminacy is the absence of an explicit reference to time . Thus, a society that agrees on the difference principle as the proper justification of basic political-economic institutions, might nevertheless disagree on whether their specific institutions are justified by that principle. Such disagreement would most often centre on issues of fact: (...) will a more egalitarian policy in fact prioritize the least well off or will a more libertarian policy do so? But facts are not the only possible points of contention. According to the fundamental indeterminacy, considering merely the sum of advantages to the least well off, the difference principle is indifferent among different flows of equal income over time. It cannot adjudicate among more or less unequal distributions across social groups when the sum income of the least advantaged group is constant. The fundamental indeterminacy lies at the bottom of three derivative indeterminacies: an adequate future discount rate, an acceptable absolute minimum, and a reasonable time interval. These might form the basis of political disagreement among self-proclaimed endorsers of the difference principle of left and right over the way the principal social-economic institutions ought to be structured and the distributions that ensue. Key Words: Rawls • equality • incentives • future discount rate • primary goods • well-being. (shrink)

In Principles I. 53, Descartes states what appears to be an important metaphysical principle: P1: Each substance has one principal property, which constitutes its nature and essence, and to which all its other properties are referred (AT VIIIA 25; CSM I 210).1 Marleen Rozemond calls this Descartes's "Attributes Premise", and it leads directly, as she points out, to Cartesian Dualism, the doctrine that a human mind and a human body, even when they belong to the same human being, (...) are distinct substances (Rozemond forthcoming). (shrink)

This book is a philosophical commentary on Schopenhauer's "Fourfold Root of the Principle of Sufficient Reason," dealing with each of Schopenhauer's principal ...

After his refutation of the doubts concerning Proposition I.7 (in the Book of solving doubts), Ibn al-Haytham mentions three possible ways in which circles may intersect, submitting them to the following “intuitive” argument: one part of one of the two circles is situated inside of the other circle, and its other part is situated outside of it. One is therefore tempted to believe that the commentator accepts the principle of continuity in the case of circles, since his argument has (...) the following meaning: if a circle is divisible into two parts (or, again, passes through two points), one of which (or one of the two points) is situated inside the other circle, and the other outside of it, then the two circles cut one another. The author of this article proposes to establish the limits of this belief, on the basis of the following reflections: 1). It will be noted first of all that what could be called the ‘principle of the intersection of circles’ does not constitute ipso facto a principle in the mind of Ibn al-Haytham: no allusion is made to it in the commentary on Proposition I.1, among others. 2) It will be established later on that if one accepts (according to the explanation of Ibn al-Haytham in his Commentary on the premisses) that a line is the result of the movement of a point, the principle of continuity should be considered by him as something which is obvious by itself, without being stated. This conclusion will be based on an analysis of the notion of continuity in its classical meaning, and on Ibn al-Haytham’s commentary on Proposition X.1. 3) On the other hand, we should note the presence of a ‘sketch’ of topological language, which Ibn al-Haytham develops for the notion of a circle (particularly in the Commentary): one could say in this context that his reflection constitutes an important, if not principal, stage in the process which was to lead to the explicit formulation of the principle of continuity. Footnotes1 Je voudrais remercier chaleureusement Monsieur R. Rashed d'avoir bien voulu lire la première version de cet article, m'envoyer certaines de ses publications et me communiquer ses suggestions dont j'ai essayé de tirer le plus grand profit dans la révision que voici. Toutes les insuffisances qui s'y trouvent ne peuvent que m'être imputées. (shrink)

The aim of this paper is to derive a perfectly general criterion of identity through time from Locke’s Principle, which says that two things of the same kind cannot occupy the same space at the same time. In this way, the paper pursues a suggestion made by Peter F. Strawson almost thirty years ago in an article called ‘Entity and Identity’. The reason why the potential of this suggestion has so far remained unrealized is twofold: firstly, the suggestion was (...) never properly developed by Strawson, and secondly, it seemed vulnerable to an objection that he himself raised against it. Consequently, the paper’s aim is to further develop Strawson’s suggestion, and to show that the result is not vulnerable to the objection that seemed fatal to its underdeveloped predecessor. In addition, the paper aims to defend Locke’s Principle against alleged counterexamples such as those produced by Leibniz, Fine and Hughes. (shrink)

In this paper I argue that the enkratic principle in its classic formulation is not a requirement of rationality. However, it is a requirement of another kind, an agential requirement. I discuss how we can distinguish rational requirements from agential requirements, and why both kinds of requirements are important for understanding our expectations about individual agents.

I argue against Rawls's claim that the liberal principle of legitimacy would be selected in the original position in addition to a democratic principle. Since a religious democracy could satisfy the democratic principle, the parties in the original position would not exclude it as illegitimate.

I make the observation that English sentences such as “You have reason to take the bus or to take the train” do not have the logical form that they superficially appear to have. I find in these sentences a conjunctive use of “or,” as found in sentences like “You can have milk or lemon in your tea,” which gives you a permission to have milk, and a permission to have lemon, though no permission to have both. I argue that a (...) confusion of genuine disjunctions with sentences of the above form has motivated the mistaken acceptance by some philosophers of principles like the one I call “Liberal Transmission.” This is the principle that if you have a reason to do something, then you have a reason to do it in each of the possible ways in which it can be done (though not more than one of them). I argue that Liberal Transmission and its close relatives are false. Wide-scope reasons are defined as reasons that have a conditional or other logical connective within the scope of the reason operator. For example, a wide-scope instrumental reason might be: reason(if you have an end, take the means). By refuting Liberal Transmission, I show that you could have wide-scope instrumental reasons like this while nevertheless lacking any narrow-scope reason to take the means, or narrow-scope reason to not have the end. This enables me to respond to two major objections to the wide-scope approach to the instrumental principle that have been developed by Joseph Raz and by Niko Kolodny. (shrink)

There are at least three core principles that define the chance role: (1) the Principal Principle, (2) the Basic Chance Principle, and (3) the Humean Principle. These principles seem mutually incompatible. At least, no extant account of chance meets more than one of them. I offer an account of chance which meets all three: L*-chance. So the good news is that L*-chance meets (1)–(3). The bad news is that L*-chance turns out unlawful and unstable.

Ever since Copernicus, scientists have continually adjusted their view of human nature, moving it further and further from its ancient position at the center of Creation. But in recent years, a startling new concept has evolved that places it more firmly than ever in a special position. Known as the Anthropic Cosmological Principle, this collection of ideas holds that the existence of intelligent observers determines the fundamental structure of the Universe. In its most radical version, the Anthropic Principle (...) asserts that "intelligent information-processing must come into existence in the Universe, and once it comes into existence, it will never die out." This wide-ranging and detailed book explores the many ramifications of the Anthropic Cosmological Principle, covering the whole spectrum of human inquiry from Aristotle to Z bosons. Bringing a unique combination of skills and knowledge to the subject, John D. Barrow and Frank J. Tipler--two of the world's leading cosmologists--cover the definition and nature of life, the search for extraterrestrial intelligence, and the interpretation of the quantum theory in relation to the existence of observers. The book will be of vital interest to philosophers, theologians, mathematicians, scientists, and historians, as well as to anyone concerned with the connection between the vastness of the universe of stars and galaxies and the existence of life within it on a small planet out in the suburbs of the Milky Way. (shrink)

In this article, I derive a weak version of Kant's categorical imperative within an informal game-theoretic framework. More specifically, I argue that Hobbesian agents would choose what I call the weak principle of universalization, if they had to decide on a rule of conflict resolution in an idealized but empirically defensible hypothetical decision situation. The discussion clarifies (i) the rationality requirements imposed on agents, (ii) the empirical conditions assumed to warrant the conclusion, and (iii) the political institutions that are (...) necessary to implement the derived principle. The analysis demonstrates the moral significance of the weak principle of universalization and its epistemic advantage over the categorical imperative. (shrink)

The term action of consciousness is used to refer to an influence, such as psychokinesis or free will, that produces an effect on matter that is correlated to mental intention, but not completely determined by physical conditions. Such an action could not conserve energy. But in that case, one wonders why, when highly accurate measurements are done, occasions of non-conserved energy (generated perhaps by unconscious PK) are not detected. A possible explanation is that actions of consciousness take place within the (...) limits of the uncertainty principle. Two models are reviewed that, using the latter assumption, propose that consciousness can originate an action potential in the brain. One (that of Eccles) uses the latter assumption only, and the other (that of Burns) additionally assumes that consciousness acts, within those limits, by ordering quantum fluctuations. (shrink)

On the ground of Kant’s reformulation of the principle of con- tradiction, a non-classical logic KC and its extension KC+ are constructed. In KC and KC+, \neg(\phi \wedge \neg\phi),  \phi \rightarrow (\neg\phi \rightarrow \phi), and  \phi \vee \neg\phi are not valid due to specific changes in the meaning of connectives and quantifiers, although there is the explosion of derivable consequences from {\phi, ¬\phi} (the deduc- tion theorem lacking). KC and KC+ are interpreted as fragments of an S5-based (...) first-order modal logic M. The quantification in M is combined with a “subject abstraction” device, which excepts predicate letters from the scope of modal operators. Derivability is defined by an appropriate labelled tableau system rules. Informally, KC is mainly ontologically motivated (in contrast, for example, to Jaśkowski’s discussive logic), relativizing state of affairs with respect to conditions such as time. (shrink)

The paper examines the relationship between the two parts of Rawls’ second principle of justice. More specifically, it explores the ways in which the Difference Principle (DP) may constrain the range of acceptable social arrangements in light of the stated lexical priority of the requirement of fair equality of opportunity (FEO) over the DP. The paper discusses two possibilities. First, it examines the role the DP may play within an institutional scheme that satisfies the requirement of FEO. Second, (...) it discusses the role the principle may play in selecting among different institutional schemes that satisfy FEO. The paper argues that the DP has an important role only if there is a range of institutional arrangements that are equivalent from the point of view of FEO but non-equivalent from the point of view of the DP. Next, it explores the possible sources of the variation among the different FEO-equivalent institutional schemes, and argues that on the most satisfactory reading of the requirement of FEO, there will not be much variation that is relevant from the point of view of the DP. The paper concludes that the role of the Difference Principle is at best very limited in constraining the range of social arrangements that are acceptable from the point of view of justice. (shrink)

The acquaintance principle (AP) and the view it expresses have recently been tied to a debate surrounding the possibility of aesthetic testimony, which, plainly put, deals with the question whether aesthetic knowledge can be acquired through testimony—typically aesthetic and non-aesthetic descriptions communicated from person to person. In this context a number of suggestions have been put forward opting for a restricted acceptance of AP. This paper is an attempt to restrict AP even more.

Davies argues that the ontology of artworks as performances offers a principled way of explaining work-relativity of modality. Object oriented contextualist ontologies of art (Levinson) cannot adequately address the problem of work-relativity of modal properties because they understand looseness in what counts as the same context as a view that slight differences in the work-constitutive features of provenance are work-relative. I argue that it is more in the spirit of contextualism to understand looseness as context-dependent. This points to the general (...) problem—the context of appreciation is not robust enough to ground modal intuitions about objective entities. In general, when epistemology dictates ontology there is always a threat of anti-realism, scepticism and relativism. Davies also appeals to the modality principle—an entity’s essential properties are all and only its constitutive properties. Davies understands essentiality in a traditional way: a property P is an essential property of an object o iff o could not exist and lack P. Kit Fine has recently made a convincing case for the view that the notion of essence is not to be understood in modal terms. I explore some of the implications of this view for Davies’ modal argument for the performance theory. (shrink)

The precautionary principle has its origins in debates about environmental policy, but is increasingly invoked in bioethical contexts. John Harris and Søren Holm argue that the principle should be rejected as incoherent, irrational, and representing a fundamental threat to scientific advance and technological progress. This article argues that while there are problems with standard formulations of the principle, Harris and Holm's rejection of all its forms is mistaken. In particular, they focus on strong versions of the (...) class='Hi'>principle and fail to recognize that weaker forms, which may escape their criticisms, are both possible and advocated in the literature. (shrink)

The Pareto principle states that if the members of society express the same preference judgment between two options, this judgment is compelling for society. A building block of normative economics and social choice theory, and often borrowed by contemporary political philosophy, the principle has rarely been subjected to philosophical criticism. The paper objects to it on the ground that it indifferently applies to those cases in which the individuals agree on both their expressed preferences and their reasons for (...) entertaining them, and those cases in which they agree on their expressed preferences, while differing on their reasons. The latter are cases of "spurious unanimity", and it is normatively inappropriate, or so the paper argues, to defend unanimity preservation at the social level for them, so the Pareto principle is formulated much too broadly. The objection seems especially powerful when the principle is applied in an ex ante context of uncertainty, in which individuals can disagree on both their probabilities and utilities, and nonetheless agree on their preferences over prospects. (shrink)

Lewis’ Principal Principle (PP) aims at clarifying the connection between chance (i.e. objective probability) and credence (i.e. subjective probability). It is generally assumed that the chance that an event will occur does not depend on our credence in the occurrence of that event. Nevertheless, chances constrain our credence, and Lewis’ PP is an attempt to capture this connection.

The “puzzle of the unmarked clock” derives from a conflict between the following: (1) a plausible principle of epistemic modesty, and (2) “Rational Reflection”, a principle saying how one’s beliefs about what it is rational to believe constrain the rest of one’s beliefs. An independently motivated improvement to Rational Reflection preserves its spirit while resolving the conflict.

In this paper, I argue that the ‘modified youngest first’ principle provides a morally appropriate criterion for making decisions regarding the distribution of scarce medical resources, and that it is morally preferable to the simple ‘youngest first’ principle. Based on the complete lives system's goal of maximizing complete lives rather than individual life episodes, I argue that essential to the value we see in complete lives is the first person value attributed by the experiencer of that life. For (...) a life to be ‘complete’ or ‘incomplete,’ the subject of that life must be able to understand the concept of a complete life, to have started goals and projects, and to know what it would be for that life to be complete. As the very young are not able to do this, it can reasonably be said that their characteristically human lives have not yet begun, giving those accepting a complete lives approach good reason to accept the modified youngest first principle over a simple ‘youngest first’ approach. (shrink)

In Psychosemantics Fodor presents three arguments for preferring the language of thought over mere intentional realism - arguments for the conclusion that intentional causes of behavior have constituent structure. The first of these, relying on the methodological 'Principle P', is considered in detail here and is found wanting. This principle does not prefer the language of thought to those very connectionist systems which Fodor criticizes; and it rests on dubious theoretical and empirical assumptions.

The aim of this work is to analyse the diffrerences between the formal structure of anticipation of perception in classical and in quantum context. I argue that a transcendental point of view can be supported in quantum context if objectivity is defined by an invariant anticipative structure, which has only a predictive character. The classical objectivity, which defined a set of properties having a descriptive meaning must be abandoned in quantum context. I will focus my analysis on Kant's Principle (...) of the Anticipations of Perception. (shrink)

Let the chain antichain principle (CAC) be the statement that each partial order on $\mathbb{N}$ possesses an infinite chain or an infinite antichain. Chong, Slaman, and Yang recently proved using forcing over nonstandard models of arithmetic that CAC is $\Pi^1_1$-conservative over $\text{RCA}_0+\Pi^0_1\text{-CP}$ and so in particular that CAC does not imply $\Sigma^0_2$-induction. We provide here a different purely syntactical and constructive proof of the statement that CAC (even together with WKL) does not imply $\Sigma^0_2$-induction. In detail we show using (...) a refinement of Howard's ordinal analysis of bar recursion that $\text{WKL}_0^\omega+\text{CAC}$ is $\Pi^0_2$-conservative over PRA and that one can extract primitive recursive realizers for such statements. Moreover, our proof is finitary in the sense of Hilbert's program. CAC implies that every sequence of $\mathbb{R}$ has a monotone subsequence. This Bolzano-Weierstraß}-like principle is commonly used in proofs. Our result makes it possible to extract primitive recursive terms from such proofs. We also discuss the Erdős-Moser principle, which—taken together with CAC—is equivalent to $\text{RT}^2_2$. (shrink)

The debate concerning the moral permissibility of using human embryos in human embryonic stem cell (hESC) research has long centred on the question of the embryo's supposed right to life. However, in focussing only on this question, many opponents to hESC research have escaped rigorous scrutiny by making vague and unfounded appeals to the concept of moral respect in order to justify their opposition to certain hESC practices. In this paper, I offer a critical analysis of the concept of moral (...) respect, and its use to support the intuitively appealing principle of proportionality in hESC research. I argue that if proponents of this principle are to justify its adoption by appealing to the concept of moral respect, they must explain two things concerning the nature of the moral respect owed to embryos. First, they must explain which particular aspect of the embryo is morally relevant, and why. Second, they must explain why some uses of embryos in research fail to acknowledge what is morally relevant about the embryo, and thereby involve a violation of the moral respect that they are due. I shall show that providing such explanations may be more difficult than it first appears. (shrink)

In broad outline, the chapter proceeds as follows. As indicated above, the Voluntary Act Principle has two components. The first part, the act component, claims that criminal liability can be imposed on an accused only for the performance of an act. The second part, the voluntariness component, claims that criminal liability can be imposed on an accused only for the voluntary performance of an act. I will argue that both components of the Voluntary Act Principle are in need (...) of amendment. I will first indicate why I think the act component of the Voluntary Act Principle is in tension with the criminal law’s own conception of the necessary conditions for criminal liability, and suggest a relatively simple fix. I will then argue that what is really at work in the voluntariness component of the Voluntary Act Principle is not so much voluntariness but rather what some authors have called the practical agency condition. In making my argument I will appeal to Harry Frankfurt’s hierarchical account of the will in the hopes of illuminating what it means for an action to belong to an agent, and thus, what it means for an agent to be responsible for something she has done. (shrink)

According to Principles of Sufficient Reason, every truth (in some relevant group) has an explanation. One of the most popular defenses of Principles of Sufficient Reason has been the presupposition of reason defense, which takes endorsement of the defended PSR to play a crucial role in our theory selection. According to recent presentations of this defense, our method of theory selection often depends on the assumption that, if a given proposition is true, then it has an explanation, and this will (...) only be justified if we think this holds for all propositions in the relevant group. I argue that this argument fails even when restricted to contingent propositions, and even if we grant that there is no non-arbitrary way to divide true propositions that have explanations from those that lack them. Further, we can give an alternate explanation of what justifies our selecting theories on the basis of explanatory features: the crucial role is not played by an endorsement of a PSR, but rather by our belief that, prima facie, we should prefer theories that exemplify explanatory power to greater degrees than their rivals. This guides our theory selection in a manner similar to ontological parsimony and theoretical simplicity. Unlike a PSR, our belief about explanatory power gives us a prima facie guiding principle, which provides justification in the cases where we think we have it, and not in the cases where we think we don't. (shrink)

We offer a review of some of the most influential views on the status of Reichenbach’s Principle of the Common Cause (RPCC) for genuinely indeterministic systems. We first argue that the RPCC is properly a conjunction of two distinct claims, one metaphysical and another methodological. Both claims can and have been contested in the literature, but here we simply assume that the metaphysical claim is correct, in order to focus our analysis on the status of the methodological claim. We (...) briefly review the most entrenched or classical positions, including Salmon’s ‘interactive forks’, van Fraassen’s scepticism, and Cartwright’s generalisation of the fork criterion. We then go on to review the results of the ‘Budapest school’ on the existence of formally defined screening­ off events for any correlation —by means of the ideas of probability space extensibility and (Reichenbachian common cause) completability. We distinguish the Budapest doctrine clearly from any of the classical conceptions, and thus present an overall framework for discussions of causal inference in quantum mechanics. We argue that this review is preliminary essential work for a thorough assessment of the conditions under which RCCP may be a reliable tool for causal inference in a genuinely probabilistic (indeterministic) context. (shrink)

Many alternatives or supplements to principalism seek to reconnect medical ethics with the thoughts, feelings, and motivations of the persons directly involved in ethically troublesome situations. This shift of attention, from deeds to doers, from principles to principals, acknowledges the importance of the moral agents involved in the situation — particular practitioners, patients, and families. Taking into account the subjective, lived experience of moral decision-making parallels recent efforts in the teaching of medicine to give the patient''s subjectivity — his or (...) her personal experience of being sick or disabled — epistemological parity with scientific medicine''s objective, biomedically-oriented view of the person''s sickness or disability.Moreover, the shift from principalism to principals signals a growing realization that ethical problems in the profession of medicine are inseparable from its practice. Philosophers and other humanists working in medicine should resist the temptation to institutionalize a professional role as solver of ethical problems, clarifier of values, or mediator of disputes and work instead to help practitioners practice medicine reflectively. (shrink)

David Lewis’s ‘Humean Supervenience’ (henceforth ‘HS’) combines realism about laws, chances, and dispositions with a sparse ontology according to which everything supervenes on the overall spatiotemporal distribution of non-dispositional properties (Lewis 1986a, Philosophical papers: Volume II, pp. ix–xvii, New York: Oxford Univesity Press, 1994, Mind 103:473–490). HS faces a serious problem—a “big bad bug” (Lewis 1986a, p. xiv): it contradicts the Principal Principle, a seemingly obvious norm of rational credence. Two authors have tried to rescue Lewis’s ontology from (...) the ‘big bad bug’ (henceforth ‘the Bug’) by rejecting realism about laws, chances, and dispositions (Halpin 1994, Aust J Phil 72:317–338, 1998, Phil Sci 65:349–360; Ward 2005, Phil Sci 71:241–261). I will argue that this strategy cannot possibly work: it is the ontology, not the realist thesis, that lies at the root of the problem. (shrink)

David Lewis's influential work on the epistemology and metaphysics of objective chance has convinced many philosophers of the central importance of the following two claims: First, it is a serious cost of reductionist positions about chance (such as that occupied by Lewis) that they are, apparently, forced to modify the Principal Principle--the central principle relating objective chance to rational subjective probability--in order to avoid contradiction. Second, it is a perhaps more serious cost of the rival non-reductionist position (...) that, unlike reductionism, it can give no coherent explanation for why the Principal Principle should hold. I argue that both of these claims are fundamentally mistaken. (shrink)

one's subjective probability for a proposition should conform to one's beliefs about that proposition's objective chance of coming true. David Lewis has argued (i) that this principle provides the defining role for chance; (ii) that it conflicts with his reductionist thesis of Humean supervenience, and so must be replaced by an amended version that avoids the conflict; hence (iii) that nothing perfectly deserves the name ‘chance’, although something can come close enough by playing the role picked out by the (...) amended principle. We show that in fact there must be ‘chances’ that perfectly play what Lewis takes to be the defining role. But this is not the happy conclusion it might seem, since these ‘chances’ behave too strangely to deserve the name. The lesson is simple: much more than the Principal Principle—more to the point, much more than the connection between chance and credence—informs our understanding of objective chance. 1 Introduction 2 Preliminaries 3 Undermining futures and the New Principle 4 The Old Principle rescued? 5 The New Bug 6 Conclusion. (shrink)

The goal of this paper is to sketch and defend a new interpretation or 'theory' of objective chance, one that lets us be sure such chances exist and shows how they can play the roles we traditionally grant them. The account is 'Humean' in claiming that objective chances supervene on the totality of actual events, but does not imply or presuppose a Humean approach to other metaphysical issues such as laws or causation. Like Lewis (1994) I take the Principal (...) Principle (PP) to be the key to understanding objective chance. After describing the main features of Humean objective chance (HOC), I deduce the validity of PP for Humean chances, and end by exploring the limitations of Humean chance. (shrink)

In this paper I want to do two things. One concerns Mill’s attitude to public indecency. In On Liberty Mill expresses the conventional view that certain actions, if conducted in public, are an affront to good manners, and can properly be prohibited. I want to come to an understanding of Mill’s position so that it allows him to defend this part of conventional morality, but does not disrupt certain of his liberal convictions: principally the conviction that what consenting adults do (...) in private is no-one ‘s concern but their own. The difficulty is to find an argument that Mill could have used to defend the position that some things which, though acceptable in private, can rightly be stopped if attempted in public. The other thing I want to do is consider the impact of Mill’s view of indecency on the interpretation of the Liberty Principle. There remain difficulties here which, to my knowledge, have not been adequately explored. So I want to look at a range of interpretative alternatives. In the first part of the paper I shall raise and explore the issue of the interpretative problems. In the second part I shall look at some ways of trying to justify Mill’s view of indecency on characteristically Millian grounds. And in the final part I shall explore the somewhat surprising consequences of the discussion of the second part for the interpretative questions raised in the first. (shrink)

This article focuses on the ethical implications of so-called ‘collateral damage’. It develops a moral typology of collateral harm to innocents which occurs as a side effect of military or quasi-military action. Distinguishing between accidental and incidental collateral damage, it introduces four categories of such damage: negligent, oblivious, knowing, and reckless collateral damage. Objecting mainstream versions of the doctrine of double effect, in the article it is argued that in order for any collateral damage to be morally permissible, violent agents (...) must comply with high standards of care. In order for incidental harm to be permissible, an agent must take pains to avoid such harm even at higher cost to him. Adding to the doctrine, it is argued that accidentally, but negligently caused collateral damage may be just as difficult to excuse as incidental harm. Only if high precautionary standards of care are met, unintended harm to innocents – incidental or accidental – can be permissible. In practice, such a strong commitment to avoiding harm to civilians may well lead us to question more generally and rethink more radically how violent conflicts ought to be fought, how military violence ought to be used and whether there are better ways of achieving those aims that we think are legitimate than those we are currently taking. (shrink)

I argue that the theory of chance proposed by David Lewis has three problems: (i) it is time asymmetric in a manner incompatible with some of the chance theories of physics, (ii) it is incompatible with statistical mechanical chances, and (iii) the content of Lewis's Principal Principle depends on how admissibility is cashed out, but there is no agreement as to what admissible evidence should be. I proposes two modifications of Lewis's theory which resolve these difficulties. I conclude (...) by tentatively proposing a third modification of Lewis's theory, one which explains many of the common features shared by the chance theories of physics. (shrink)

Recent work on probability in the Everett interpretation of quantum mechanics yields a decision-theoretic derivation of David Lewis’ Principal Principle, and hence a general metaphysical theory of probability; part 1 is a discussion of this remarkable result. I defend the claim that the ‘subjective uncertainty’ principle is required for the derivation to succeed, arguing that it amounts to a theoretical identification of chance. In part 2, I generalize this account, and suggest that the Everett interpretation, in combination (...) with a plausible view of natural laws, has the potential to provide a reductive theory of metaphysical modality. I defend the resulting naturalistic modal realism, and outline some of its implications for other parts of metaphysics. (shrink)

All parties to the Sleeping Beauty debate agree that it shows that some cherished principle of rationality has to go. Thirders think that it is Conditionalization and Reflection that must be given up or modified; halfers think that it is the Principal Principle. I offer an analysis of the Sleeping Beauty puzzle that allows us to retain all three principles. In brief, I argue that Sleeping Beauty’s credence in the uncentered proposition that the coin came up heads (...) should be 1/2, but her credence in the centered proposition that the coin came up heads and it is Monday should be 1/3. I trace the source of the earlier mistakes to an unquestioned assumption in the debate, namely that an uncentered proposition is just a special kind of centered proposition. I argue that the falsity of this assumption is the real lesson of the Sleeping Beauty case. (shrink)

The relation between chance and actuality gives rise to a puzzle. On the one hand, it may be a chancy matter what will actually happen. On the other hand, the standard semantics for ‘actually’ implies that sentences beginning with ‘actually’ are never contingent. To elucidate the puzzle, I defend a kind of objective semantic indeterminacy: in a chancy world, it may be a chancy matter which proposition is expressed by sentences containing ‘actually’. I bring this thesis to bear on certain (...) counter-examples, proposed by Hawthorne and Lasonen-Aarnio, to Lewis' ‘principal principle’. (shrink)

This article challenges the view most recently expounded by Emily Jackson that ‘decisional privacy’ ought to be respected in the realm of artificial reproduction (AR). On this view, it is considered an unjust infringement of individual liberty for the state to interfere with individual or group freedom artificially to produce a child. It is our contention that a proper evaluation of AR and of the relevance of welfare will be sensitive not only to the rights of ‘commissioning parties’ to AR (...) but also to public policy considerations. We argue that AR has implications for the common good, by involving matters of human reproduction, kinship, race, parenthood and identity. In this paper we challenge presuppositions concerning decisional privacy. We examine the essential commodification of human life implicit in AR and the systematicity that makes this possible. We address the objection that it is an ethically neutral way of having children and consider the problem of ‘existential debt’. After examining objections to the thesis that AR is illegitimate for reasons of public policy and the common good, we return to the issue of decisional privacy in the light of considerations concerning the legitimate role of the state in matters affecting human reproduction. (shrink)

The recent publication of a third anthology of Donald Davidson’s articles, and anticipated publication of two more, encourages a consideration of themes binding together Davidson’s lifetime of research. One such theme is the principle of charity (PC). In light of the mileage Davidson gets out of PC, I propose a careful examination of PC itself. In Part 1, I consider some ways in which Davidson articulates PC. In Part 2, I show that the articulation that Davidson requires in his (...) work on epistemology is untenable given what Davidson says in his work on semanties. I conclude that Davidson can use PC only in his work on semantics or not at all.La parution récente du troisième recueil d’articles de Donald Davidson, lequel devrait être suivi de deux autres, incite à examiner les thèmes qui traversent tous ses travaux. Parmi ces thèmes se trouve le principe de charité (PC). Considérant tout le parti que Davidson a tiré du PC, je me propose d’en faire un examen attentif. Dans la première partie, j’examine diverses formulations du PC par Davidson. Dansla seconde partie, je montre que la formulation qu’exigent ses travaux d’épistémologie est intenable étant donné ce qu’ll en dit dans ses travaux de sémantique. De là, je conclus que Davidson ne peut se servir du PC que dans ses travaux de sémantique ou pas du tout. (shrink)

GRW Theory postulates a stochastic mechanism assuring that every so often the wave function of a quantum system is `hit', which leaves it in a localised state. How are we to interpret the probabilities built into this mechanism? GRW theory is a firmly realist proposal and it is therefore clear that these probabilities are objective probabilities (i.e. chances). A discussion of the major theories of chance leads us to the conclusion that GRW probabilities can be understood only as either single (...) case propensities or Humean objective chances. Although single case propensities have some intuitive appeal in the context of GRW theory, on balance it seems that Humean objective chances are preferable on conceptual grounds because single case propensities suffer from various well know problems such as unlimited frequency tolerance and lack of a rationalisation of the principal principle. (shrink)

According to principles of probability coordination, such as Miller's Principle or Lewis's Principal Principle, you ought to set your subjective probability for an event equal to what you take to be the objective probability of the event. For example, you should expect events with a very high probability to occur and those with a very low probability not to occur. This paper examines the grounds of such principles. It is argued that any attempt to justify a (...) class='Hi'>principle of probability coordination encounters the same difficulties as attempts to justify induction. As a result, no justification can be found. (shrink)

Jules Coleman, one of the world's leading philosophers of law, here presents his most mature work so far on substantive issues in legal theory and the appropriate methodology for legal theorizing. In doing so, he takes on the views of highly respected contemporaries such as Brian Leiter, Stephen Perry, and Ronald Dworkin.

I develop a general framework with a rationality constraint that shows how coherently to represent and deal with second-order information about one's own judgmental reliability. It is a rejection of and generalization away from the typical Bayesian requirements of unconditional judgmental self-respect and perfect knowledge of one's own beliefs, and is defended by appeal to the Principal Principle. This yields consequences about maintaining unity of the self, about symmetries and asymmetries between the first- and third-person, and a principled (...) way of knowing when to stop second-guessing oneself. Peer disagreement is treated as a special case where one doubts oneself because of news that an intellectual equal disagrees. This framework, and variants of it, imply that the typically stated belief that an equally reliably peer disagrees is incoherent, and thus that pure rationality constraints without further substantive information cannot give an answer as to what to do. The framework also shows that treating both ourselves and others as thermometers in the disagreement situation does not imply the Equal Weight view. (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)

This paper explores how the Bayesian program benefits from allowing for objective chance as well as subjective degree of belief. It applies David Lewis’s Principal Principle and David Christensen’s principle of informed preference to defend Howard Raiffa’s appeal to preferences between reference lotteries and scaling lotteries to represent degrees of belief. It goes on to outline the role of objective lotteries in an application of rationality axioms equivalent to the existence of a utility assignment to represent preferences (...) in Savage’s famous omelet example of a rational choice problem. An example motivating causal decision theory illustrates the need for representing subjunctive dependencies to do justice to intuitive examples where epistemic and causal independence come apart. We argue to extend Lewis’s account of chance as a guide to epistemic probability to include De Finetti’s convergence results. We explore Diachronic Dutch book arguments as illustrating commitments for treating transitions as learning experiences. Finally, we explore implications for Martingale convergence results for motivating commitment to objective chances. (shrink)

Newcomb problems turn on a tension between two principles of choice: roughly, a principle sensitive to the causal features of the relevant situation, and a principle sensitive only to evidential factors. Two-boxers give priority to causal beliefs, and one-boxers to evidential beliefs. A similar issue can arise when the modality in question is chance, rather than causation. In this case, the conflict is between decision rules based on credences guided solely by chances, and rules based on credences guided (...) by other sorts of probabilistic evidence. Far from excluding cases of the latter kind, Lewis’s Principal Principle explicitly allows for them, in the form of the caveat that credences should only follow beliefs about chances in the absence of "inadmissible evidence". In this paper I exhibit a tension in Lewis’s views on these two matters. I present a class of decision problems –- actually, I argue, a species of Newcomb problem –- in which Lewis’s view of the relevance of inadmissible evidence seems to recommend one-boxing, while his causal decision theory recommends two-boxing. I propose a diagnosis for this dilemma, and suggest a remedy, based on an extension of a proposal due to Ned Hall and others from the case of chance to that of causation. The remedy dissolves many apparent Newcomb problems, and makes one-boxing non-controversial in those that remain. (shrink)

It is a standard view that the concept of chance is inextricably related to the technical concept of credence . One influential version of this view is that the chance role is specified by (something in the neighborhood of) David Lewis's Principal Principle, which asserts a certain definite relation between chance and credence. If this view is right, then one cannot coherently affirm that there are chance processes in the physical world while rejecting the theoretical framework in which (...) credence is defined, namely the Bayesian framework. This is surprising; why should adopting a theory that says there are chances at work in nature put any particular constraints on our theorizing about epistemology and rational choice? It is quite plausible that in order for anything to count as the referent of our concept chance , it would have to be related to epistemic rationality in a certain way—roughly, it is rational to have more confidence that something will happen the greater you think its chance is. But this commonsensical idea does not seem to be inherently committed to any particular theoretical approach to rationality, so why should we think that adopting the Bayesian approach is a prerequisite for thinking coherently about chance? I propose and defend a replacement for the Principal Principle which makes no use of the concept of credence. I also argue that this replacement is advantageous for the project of theorizing about the nature of chance. (shrink)

An extended analysis is given of the program, originally suggested by Deutsch, of solving the probability problem in the Everett interpretation by means of decision theory. Deutsch's own proof is discussed, and alternatives are presented which are based upon different decision theories and upon Gleason's Theorem. It is argued that decision theory gives Everettians most or all of what they need from `probability'. Contact is made with Lewis's Principal Principle linking subjective credence with objective chance: an Everettian (...) class='Hi'>Principal Principle is formulated, and shown to be at least as defensible as the usual Principle. Some consequences of (Everettian) quantum mechanics for decision theory itself are also discussed. -/- [NB: this this long (70 pages) and occasionally rambling online-only paper has been almost entirely superseded by material in subsequent; if something is not included in them it usually means that I have had second thoughts. I include it for completeness only. (shrink)

Does the Bayesian theory of confirmation put real constraints on our inductive behavior? Or is it just a framework for systematizing whatever kind of inductive behavior we prefer? Colin Howson (Hume's Problem) has recently championed the second view. I argue that he is wrong, in that the Bayesian apparatus as it is usually deployed does constrain our judgments of inductive import, but also that he is right, in that the source of Bayesianism's inductive prescriptions is not the Bayesian machinery itself, (...) but rather what David Lewis calls the ``Principal Principle''. (shrink)

The Doomsday argument purports to show that the risk of the human species going extinct soon has been systematically underestimated. This argument has something in common with controversial forms of reasoning in other areas, including: game theoretic problems with imperfect recall, the methodology of cosmology, the epistemology of indexical belief, and the debate over so-called fine-tuning arguments for the design hypothesis. The common denominator is a certain premiss: the Self-Sampling Assumption. We present two strands of argument in favor of this (...) assumption. Through a series of thought experiments we then investigate some bizarre prima facie consequences – backward causation, psychic powers, and an apparent conflict with the Principal Principle. (shrink)

Taking precautions to prevent harm. Whether principe de précaution, Vorsorgeprinzip, føre-var prinsippet, or försiktighetsprincip, etc., the precautionary principle embodies the idea that public and private interests should act to prevent harm. Furthermore, the precautionary principle suggests that action should be taken to limit, regulate, or prevent potentially dangerous undertakings even in the absence of absolute scientific proof. Such measures also naturally entail taking economic costs into account. With the environmental disasters of the 1980s, the precautionary principle established (...) itself as an operational concept. On the eve of the 1997 Climate Summit in Kyoto, precaution, as the precautionary principle is often referred to, has now become a key legal principle in environmental law, in general, and in current international climate negotiations, in particular, attempts to understand why. It examines in turn the natural affinity between the precautionary principle and climate change, reviews a series of issues which the principle raises, and discusses avenues which it opens paper, climate change fulfills the theoretical requirements set for the application of the precautionary principle. It comes as no surprise that the actual application of the precautionary principle in the context of climate change raises high political stakes. As a result, climate change science, in particular, and science, in general, is under the fire of politically-motivated scientific skeptics. Thus, by way of the counter-measures which must be put into effect, the precautionary principle calls for a greater sense of responsibility on the part of scientists and the public at large. Specifically, from scientists, it demands perseverance in rigor, excellence in communication, and committment to education. However, even if special efforts are made to implement the precautionary principle in the context of climate change, the success of climate change mitigation will constitute no test of the validity, the usefulness, or the efficiency of the precautionary principle. Indeed, the degree to which climate change mitigation succeeds only provides a measure of our kind's ability to manage responsibly the global commons which we inherited from our ancestors and which our generation enjoys, the global commons which we will pass on to today's children and to generations to come. (shrink)

Probab ility (probability; subjective and objective probability; the Principal Principle; independence and correlation; conditional probability; material, indicative and subjunctive conditionals; correlation and causation; screening off; Simpson’s paradox; Bayes’ theorem; Bayesian updating).

In “A Subjectivist’s Guide to Objective Chance,” David Lewis says that he is “led to wonder whether anyone but a subjectivist is in a position to understand objective chance.” The present essay aims to motivate this same Lewisean attitude, and a similar degree of modest subjectivism, with respect to objective causation. The essay begins with Newcomb problems, which turn on an apparent tension between two principles of choice: roughly, a principle sensitive to the causal features of the relevant situation, (...) and a principle sensitive only to evidential factors. Two-boxers give priority to causal beliefs, and one-boxers to evidential beliefs. The essay notes that a similar issue can arise when the modality in question is chance, rather than causation. In this case, the conflict is between decision rules based on credences guided solely by chances, and rules based on credences guided by other sorts of probabilistic evidence. Far from excluding cases of the latter kind, Lewis’s Principal Principle explicitly allows for them, in the form of the caveat that credences should follow beliefs about chances only in the absence of “inadmissible evidence.” The essay then exhibits a tension in Lewis’s views on these two matters, by presenting a class of decision problems—some of them themselves Newcomb problems—in which Lewis’s view of the relevance of inadmissible evidence seems in tension with his causal decision theory. It offers a diagnosis for this dilemma and proposes a remedy, based on an extension of a proposal due to Ned Hall and others from the case of chance to that of causation. The remedy suggests a new view of the relation between causal decision theory and evidential decision theory, namely, that they stand to each other much as chance stands to credence, being objective and subjective faces of the same practical coin. This has much the same metaphysical benefits as Lewis’s own view of chance and also throws interesting new light on Newcomb problems, providing an irenic resolution of the apparent disagreement between causal and evidential decision rules. (shrink)

The story of the fall and rise of Zahavi’s handicap principle is one of a battle between models. Early attempts at formal modeling produced negative results and, unsurprisingly, scepticism about the principle. A major change came in 1990 with Grafen’s production of coherent models of a handicap mechanism of honest signalling. This paper’s first claim is that acceptance of the principle, and its dissemination into other disciplines, has been driven principally by that, and subsequent modeling, rather than (...) by empirical results. Secondly, there is a vast literature on biological signalling but few studies that make all of the observations necessary to diagnose the handicap mechanism. My final claim is that many of the applications of costly signalling theory in other disciplines are conceptually confused. Misinterpretations of what is meant by costly signalling are common. Demonstrating that a signal is costly is insufficient and is not always necessary in order to prove that, and explain why, a signal is honest. In addition to the biological modelling of signals, there is an economic literature on the same subject. The two run in parallel in the sense that they have had little mutual interaction. Additionally, it is the biological modelling that has been picked up, and often misapplied, by other disciplines. (shrink)

Although Bayesian methods are widely used in phylogenetic systematics today, the foundations of this methodology are still debated among both biologists and philosophers. The Bayesian approach to phylogenetic inference requires the assignment of prior probabilities to phylogenetic trees. As in other applications of Bayesian epistemology, the question of whether there is an objective way to assign these prior probabilities is a contested issue. This paper discusses the strategy of constraining the prior probabilities of phylogenetic trees by means of the (...) class='Hi'>Principal Principle. In particular, I discuss a proposal due to Velasco (Biol Philos 23:455–473, 2008) of assigning prior probabilities to tree topologies based on the Yule process. By invoking the Principal Principle I argue that prior probabilities of tree topologies should rather be assigned a weighted mixture of probability distributions based on Pinelis’ (P Roy Soc Lond B Bio 270:1425–1431, 2003) multi-rate branching process including both the Yule distribution and the uniform distribution. However, I argue that this solves the problem of the priors of phylogenetic trees only in a weak form. (shrink)

The existence of "undermining futures" appears to show that a contradiction can be deduced from the conjunction of Humean supervenience (HS) about chance and the Principal Principle. A number of strategies for rescuing HS from this problem have been proposed recently. In this paper, a novel way of defending HS from the threat is presented, and it is argued that this defense has advantages not shared by others. In particular, it requires no revisionism about chance, and it is (...) equally available to defenders of HS who hold HS to be necessary and those who hold it to be contingent. (shrink)

I follow Hájek (Synthese 137:273–323, 2003c) by taking objective probability to be a function of two propositional arguments—that is, I take conditional probability as primitive. Writing the objective probability of q given r as P(q, r), I argue that r may be chosen to provide less than a complete and exact description of the world’s history or of its state at any time. It follows that nontrivial objective probabilities are possible in deterministic worlds and about the past. A very simple (...) chance–credence relation is also then natural, namely that reasonable credence equals objective probability. In other words, we should set our actual credence in a proposition equal to the proposition’s objective probability conditional on available background information. One advantage of that approach is that the background information is not subject to an admissibility requirement, as it is in standard formulations of the Principal Principle. Another advantage is that the “undermining” usually thought to follow from Humean supervenience can be avoided. Taking objective probability to be a two-argument function is not merely a technical matter, but provides us with vital flexibility in addressing significant philosophical issues. (shrink)

considers what I call free-floating chances—objective chances that obtain at a given time despite the fact that their values are not determined by the laws of nature together with the full history of non-chancy facts up to that time. I offer an intuitive example of this phenomenon, and use it to argue that free-floating chances are indeed possible. Their possibility violates three quite widely held principles about chances: the lawful magnitude principle, the principle that chances evolve by conditionalization (...) and a version of David Lewis' principal principle. I argue that we should reject common formulations of each of these principles, though I offer revised understandings of each which retain much of the intuitive attractiveness of the originals and are consistent with the possibility of free-floating chances. I conclude by arguing that, while considerations of free-floating chances are important, they will not sustain the extravagant conclusions Lange attempts to draw from them. Introduction First- and Higher-Order Chances Free-Floating Chances Support for the Intuitive Assessment Three Principles Violated What to do? COND as a Default Hypothesis A More Principled Principal Principle Conclusion. (shrink)

This paper offers some reflections on the concepts of objective and subjective probability and Lewis' Principal Principle.

I consider Dutch Book arguments for three principles of classical Bayesianism: (i) agents' belief-probabilities are consistent only if they obey the probability axioms. (ii) beliefs are updated by Bayesian conditionalisation. (iii) that the so-called Principal Principle connects statistical and belief probabilities. I argue that while there is a sound Dutch Book argument for (i), the standard ones for (ii) based on the Lewis-Teller strategy are unsound, for reasons pointed out by Christensen. I consider a type of Dutch Book (...) argument for (iii), where the statistical probability is a von Mises one. (shrink)

In this bracing book, Fish argues that there is no realm of higher order impartiality--no neutral or fair territory on which to stake a claim--and that those ...

A principle is a starting point of departure as well as a rule. In science principles are either alleged evident rules or generalizations of already accepted laws, or formal determinations for objects tn a given domam. Thus two problems arise: first, does their nature have a conventional character? and sencond, what kind of truth is to be assigned to them. In philosophy principles are taken as a method of thinking as well as fundamental experiences. Even though they are points (...) of departure, their true meaning is known only after a philosophical job is done. Thus, paradoxically enough, we can say that in both science and philosophy a principle is at the same time in the begining and in the end. (shrink)

The Principal Principle (PP) says that,for any proposition A, given any admissible evidenceand the proposition that the chance of A is x%,one's conditional credence in A should be x%. HumeanSupervenience (HS) claims that, among possible worldslike ours, no two differ without differing inthe spacetime-point-by-spacetime-point arrangement oflocal properties. David Lewis (1986b, 1994a)has argued that PP contradicts HS, and thevalidity of his argument has been endorsed byBigelow et al. (1993),Thau (1994),Hall (1994),Strevens (1995),Ismael (1996),Hoefer (1997), and Black (1998).Against this consensus, I (...) argue thatPP might not contradict HS: Lewis'sargument is invalid, and every attempt – withina broad class of attempts – toamend the argument fails. (shrink)

It is widely acknowledged that moral principles are not sufficient to guide moral thought and action: they need to be supplemented by a capacity for judgement. However, why can we not rely on this capacity for moral judgement alone? Why do moral principles need to be supplemented, but are not supplanted, by judgement? So-called moral particularists argue that we can, and should, make moral decisions on a case-by-case basis without any principles. According to particularists, the person of moral judgement is (...) a person of empathy, sensibility and virtue, rather than a person of principle. In this paper I argue that this is a false dichotomy. The person of good moral judgement is a person of principle. I propose that we think of moral principles as internalised long-term commitments that form our moral character and sensitivity, and, as such, are constitutive of moral judgement. (shrink)

I carry out in this paper a philosophical analysis of the principle of excluded middle (or, as it is often called in the version I favor here, principle of bivalence: any meaningful assertion is either true or false). This principle has been criticized, and sometimes rejected, on the charge that its validity depends on presuppositions that are not, some believe, universally obtainable; in particular, that any well-posed problem is solvable. My goal here is to show that, although (...) excluded middle does indeed rest on certain presuppositions, they do not have the character of hypotheses that may or may not be true, or matters of fact that may or may not be the case. These presuppositions have, I claim, a transcendental character. Hence, the acceptance of excluded middle does not necessarily require, as some have claimed, an allegiance to ontological realism or some sort of cognitive optimism, construed as factual theses concerning the ontological status of domains of objects and our capability of accessing them cognitively. DOI:10.5007/1808-1711.2011v15n2p333. (shrink)

It is argued that recent discussion of the principle of the identity of indiscernibles (PII) and quantum mechanics has lost sight of the broader philosophical motivation and significance of PII and that the `received view' of the status of PII in the light of quantum mechanics survives recent criticisms of it by Muller, Saunders, and Seevinck.

The goals of this paper are two-fold: I wish to clarify the Aristotelian conception of the law of non-contradiction as a metaphysical rather than a semantic or logical principle, and to defend the truth of the principle in this sense. First I will explain what it in fact means that the law of non-contradiction is a metaphysical principle. The core idea is that the law of non-contradiction is a general principle derived from how things are in (...) the world. For example, there are certain constraints as to what kind of properties an object can have, and especially: some of these properties are mutually exclusive. Given this characterisation, I will advance to examine what kind of challenges the law of non-contradiction faces; the main opponent here is Graham Priest. I will consider these challenges and conclude that they do not threaten the truth of the law of non-contradiction understood as a metaphysical principle. (shrink)

According to Parfit, the best version of Kantian ethics takes as its central principle Kantian Contractualism: the thesis that everyone ought to follow the principles whose universal acceptance everyone could rationally will. This paper examines that thesis, identifies a class of annoying counterexamples, and suggests that when Kantian Contractualism is modified in response to these examples, the resulting principle is too complex and ad hoc to serve as the 'supreme principle of morality'.

It is often argued that higher-level special-science properties cannot be causally efficacious since the lower-level physical properties on which they supervene are doing all the causal work. This claim is usually derived from an exclusion principle stating that if a higher-level property F supervenes on a physical property F* that is causally sufficient for a property G, then F cannot cause G. We employ an account of causation as difference-making to show that the truth or falsity of this (...) class='Hi'>principle is a contingent matter and derive necessary and sufficient conditions under which a version of it holds. We argue that one important instance of the principle, far from undermining non-reductive physicalism, actually supports the causal autonomy of certain higher-level properties. (shrink)

In 1969 Harry Frankfurt published his hugely influential paper 'Alternate Possibilities and Moral Responsibility' in which he claimed to present a counterexample to the so-called 'Principle of Alternate Possibilities' ('a person is morally responsible for what he has done only if he could have done otherwise'). The success of Frankfurt-style cases as counterexamples to the Principle has been much debated since. I present an objection to these cases that, in questioning their conceptual cogency, undercuts many of those debates. (...) Such cases all require a counterfactual mechanism that could cause an agent to perform an action that he cannot avoid performing. I argue that, given our concept of what it is for someone to act, this requirement is inconsistent. Frankfurt-style alleged counterexamples are cases where an agent is morally responsible for an action he performs even though, the claim goes, he could not have avoided performing that action. However, it has recently been argued, e.g. by John Fischer, that a counterexample to the Principle could be a 'Fischer-style case', i.e. a case where the agent can either perform the action or do nothing else. I argue that, although Fischer-style cases do not share the conceptual flaw common to all Frankfurt-style cases, they also fail as counterexamples to the Principle. The paper finishes with a brief discussion of the significance of the Principle of Alternate Possibilities. (shrink)