Ioannis G. Ntagkas

People with the kind of preferences that give rise to the St. Petersburg paradox are problematic---but not because there is anything wrong with infinite utilities. Rather, such people cannot assign the St. Petersburg gamble any value that any kind of outcome could possibly have. Their preferences also violate an infinitary generalization of Savage's Sure Thing Principle, which we call the *Countable Sure Thing Principle*, as well as an infinitary generalization of von Neumann and Morgenstern's Independence axiom, which we call *Countable Independence*. In violating these principles, they display foibles like those of people who deviate from standard expected utility theory in more mundane cases: they choose dominated strategies, pay to avoid information, and reject expert advice. We precisely characterize the preference relations that satisfy Countable Independence in several equivalent ways: a structural constraint on preferences, a representation theorem, and the principle we began with, that every prospect has a value that some outcome could have.

Is the fact that our universe contains fine-tuned life evidence that we live in a multiverse? Ian Hacking and Roger White influentially argue that it is not. We approach this question through a systematic framework for self-locating epistemology. As it turns out, leading approaches to self-locating evidence agree that the fact that our own universe contains fine-tuned life indeed confirms the existence of a multiverse. This convergence is no accident: we present two theorems showing that, in this setting, any updating rule that satisfies a few reasonable conditions will have the same feature. The conclusion that fine-tuned life provides evidence for a multiverse is hard to escape.

Should we make significant sacrifices to ever-so-slightly lower the chance of extremely bad outcomes, or to ever-so-slightly raise the chance of extremely good outcomes? *Fanaticism* says yes: for every bad outcome, there is a tiny chance of extreme disaster that is even worse, and for every good outcome, there is a tiny chance of an enormous good that is even better. I consider two related recent arguments for Fanaticism: Beckstead and Thomas's argument from *strange dependence on space and time*, and Wilkinson's *Indology* argument. While both arguments are instructive, neither is persuasive. In fact, the general principles that underwrite the arguments (a *separability* principle in the first case, and a *reflection* principle in the second) are *inconsistent* with Fanaticism. In both cases, though, it is possible to rehabilitate arguments for Fanaticism based on restricted versions of those principles. The situation is unstable: plausible general principles tell *against* Fanaticism, but restrictions of those same principles (with strengthened auxiliary assumptions) *support* Fanaticism. All of the consistent views that emerge are very strange.

ABSTRACT This paper explores the idea that it is instrumentally valuable to learn normative truths. We consider an argument for ‘normative hedging’ based on this principle, and examine the structure of decision-making under moral uncertainty that arises from it. But it also turns out that the value of normative information is inconsistent with the principle that learning empirical truths is instrumentally valuable. Along the way, we develop a unified framework for modeling normative and empirical uncertainty, and we conclude with a brief comment on ‘metanormative regress’.

This paper argues that the obvious validity of certain inferences involving indirect speech reports as premises and truth or falsity ascriptions as conclusions is incompatible with Davidson's so-called "paratactic" analysis of the logical form of indirect discourse. Besides disqualifying that analysis, this problem is also claimed to indicate that the analysis is doubly in tension with Davidson's metasemantic views. Specifically, it can be reconciled neither with one of Davidson's key assumptions regarding the adequacy of the kind of semantic theory he recommends nor with one of his key assumptions regarding the inadequacy of a kind of semantic theory he rejects.

Timothy Williamson has argued that, unless the speech act of assertion were supposed to be governed by his so-called Knowledge Rule, one could not explain why sentences of the form "A and I do not know that A" are unassertable. This paper advances three objections against that argument, of which the first two aim to show that, even assuming that Williamson's explanandum has been properly circumscribed, his explanation would not be correct, and the third aims to show that his explanandum has not been properly circumscribed.

Foundations of Speech Act Theoryoffers a timely, thorough and, above all, compelling examination of the complexities of illocutionary acts, performatives, and their phenomenological basis. Savas Tsohatzidis has collected an impressive range of international scholars on the subject. Clearly demonstrating the relevance of speech act theory to semantic theory, the collection further interrogates the inability of pragmatic theories of illocution to properly locate such speech acts within the logic of phenomenology and intersubjectivity.

This is a volume of original essays on key aspects of John Searle's philosophy of language. It examines Searle's work in relation to current issues of central significance, including internalism versus externalism about mental and linguistic content, truth-conditional versus non-truth-conditional conceptions of content, the relative priorities of thought and language in the explanation of intentionality, the status of the distinction between force and sense in the theory of meaning, the issue of meaning scepticism in relation to rule-following, and the proper characterization of ‘what is said’ in relation to the semantics/pragmatics distinction. Written by a distinguished team of contemporary philosophers, and prefaced by an illuminating essay by Searle, the volume aims to contribute to a deeper understanding of Searle's work in philosophy of language, and to suggest innovative approaches to fundamental questions in that area.

In this volume, Savas L. Tsohatzidis brings together a team of leading experts to provide up-to-date perspectives on the work of J. L. Austin, a major figure in twentieth-century philosophy and an important contributor to theories of language, truth, perception, and knowledge. Focusing on aspects of Austin's writings in these four areas, the volume's ten original essays critically examine central elements of his philosophy, exploring their interrelationships, their historical context, their reception, and their implications for key issues of contemporary philosophical research. The volume deepens our understanding of Austin's philosophy while illustrating its continuing significance, and will appeal to students and scholars of modern philosophy, particularly to those interested in the philosophy of language and epistemology.

The paper is a critique of the widespread conception of logic as a neutral arbiter between metaphysical theories, one that makes no `substantive’ claims of its own (David Kaplan and John Etchemendy are two recent examples). A familiar observation is that virtually every putatively fundamental principle of logic has been challenged over the last century on broadly metaphysical grounds (however mistaken), with a consequent proliferation of alternative logics. However, this apparent contentiousness of logic is often treated as though it were neutralized by the possibility of studying all these alternative logics within an agreed metalogical framework, typically that of first-order logic with set theory. In effect, metalogic is given the role of neutral arbiter. The paper will consider a variety of examples in which deep logical disputes re-emerge at the meta-level. One case is quantified modal logic, where some varieties of actualism require a modal meta-language (as opposed to the usual non-modal language of possible worlds model theory) in order not to make their denial of the Barcan formula self-defeating. Similarly, on some views the intended model theory for second-order logic can only be given in a second-order metalanguage—this may be needed to avoid versions of Russell’s paradox when the first-order quantifiers are read as absolutely unrestricted. It can be shown that the phenomenon of higher-order vagueness eventually forces fuzzy logical treatments of vagueness to use a fuzzy metalanguage, with consequent repercussions for what first-order principles are validated. The difficulty of proving the completeness of first-order intuitionistic logic on its intended interpretation by intuitionistically rather than just classically valid means is a more familiar example. These case studies will be discussed in some detail to reveal a variety of ways in which even metalogic is metaphysically contested, substantial and non-neutral.

The so-called expertise defence against sceptical challenges from experimental philosophy has recently come under attack: there are several studies claiming to have found direct evidence that philosophers’ judgments in thought experiments are susceptible to erroneous effects. In this paper, we distinguish between the customary ‘immune experts’ version of the expertise defence and an ‘informed experts’ version. On the informed expertise defence, we argue, philosophers’ judgments in thought experiments could be preferable to those by the folk even if it were true that philosophers’ judgments are no less immune to confounders than judgments by the folk are. We present results from an experimental study comparing philosophers and non-philosophers (n = 484), which support this version of the expertise defence.

In the last few decades of the twentieth century there was a revolution in metaphysics: the intensional revolution. Many metaphysicians rejected the doctrine, associated with Quine and Davidson, that extensional analyses and theoretical resources were the only acceptable ones. Metaphysicians embraced tools like modal and counterfactual analyses, claims of modal and counterfactual dependence, and entities such as possible worlds and intensionally individuated properties and relations. The twenty-first century is seeing a hypterintensional revolution. Theoretical tools in common use carve more finely than by necessary equivalence: two pieces of language can apply to the same entities across all possible worlds but not be equivalent; thoughts can be necessarily equivalent in truth value but not synonymous. This paper argues that hyperintensional resources are valuable in metaphysics outside theories of representation, and discusses some promising areas of hyperintensional metaphysics

What is conceptual art? Is it really a kind of art in its own right? Is it clever – or too clever? Of all the different art forms it is perhaps conceptual art which at once fascinates and infuriates the most. In this much-needed book Peter Goldie and Elisabeth Schellekens demystify conceptual art using the sharp tools of philosophy. They explain how conceptual art is driven by ideas rather than the manipulation of paint and physical materials; how it challenges the very basis of what we can know about art, as well as our received ideas of beauty; and why conceptual art requires us to rethink concepts fundamental to art and aesthetics, such as artistic interpretation and appreciation. Including helpful illustrations of the work of celebrated conceptual artists from Marcel Duchamp, Joseph Kosuth and Piero Manzoni to Dan Perjovschi and Martin Creed, Who’s Afraid of Conceptual Art? is a superb starting point for anyone intrigued but perplexed by conceptual art - and by art in general. It will be particularly helpful to students of philosophy, art and visual studies seeking an introduction not only to conceptual art but fundamental topics in art and aesthetics.

The procreation asymmetry is a widely held view in ethics, claiming that one should make existing people happy but has no reason to make happy people. Here, I shall present a new objection demonstrating from modest premises that one has a reason to take a sequence of actions that simply creates a happy person; yet this judgment in combination with plausible principles about sequences of actions entails that one has some reason to simply create a happy person. Additionally, I will argue that one's reasons to create a happy person are quite strong.

The self-indication assumption (SIA) claims that given that one exists, one should think that the universe has many people, for a universe that has more people is more likely to contain any particular person. SIA is attractive to many because it diffuses the infamous doomsday argument, and avoids the problems of its main rival, the self-sampling assumption (SSA), which instructs one to reason as if they’re randomly selected from the people in their reference class. Here, I will go further than the traditional argument for SIA from its ability to avoid the doomsday argument: I will show that any view other than SIA must accept the soundness of the doomsday argument and certain even stranger conclusions. Additionally, I’ll argue that the main objection to SIA, the presumptuous philosopher case, is unconvincing. Together then, these considerations give one a strong reason to adopt SIA.

Two individuals can both be ethical vegans but disagree on the normative basis of their moral beliefs. This article will look at the development of two competing theories that hold prominence in debates among animal advocates: utilitarianism and deontology. Next, we turn toward their divergence in epistemology, the moral status of experiences and individuals, and the limits of permissibility. Last, we unite utilitarianism and deontology by noting where they converge. This union comes from enlightenment thinking, the postulation of direct duties to animals, disapproval of factory farming conditions, and, most importantly, the goal of improving the lives of many animals.

This paper advances an account of truth that has as its starting point Aristotle’s comments about truth at Metaphysics 1011b1. It argues that there are two key ideas in the Aristotelian account: that truth belongs to ‘sayings that’; and that truth involves both what is said and what is. Beginning with the second of these apparent truisms, the paper argues for the crucial role of the distinction between ‘what is said’ and ‘what is’ in the understanding of truth, on the grounds that it is essential to the distinction between truth and falsity and, indeed, to the very possibility of any critical assessment of statements. However, this distinction cannot be used to ground any account of truth in terms that refer to anything other than truth—there is thus no relation that underlies truth even though truth may be construed (in a certain limited sense) relationally. Returning to the first point, it is argued that while truth should indeed be understood as belonging to statements, it should not be construed as attaching to ‘propositions’, but to uttered sentences. The account of truth advanced is minimalist, and yet not deflationist; objectivist, and yet not independent of actual linguistic practice.

Essences have been assigned important but controversial explanatory roles in philosophical, scientific, and social theorizing. Is it possible for the same organism to be first a caterpillar and then a butterfly? Is it impossible for a human being to transform into an insect like Gregor Samsa does in Franz Kafka’s The Metamorphosis? Is it impossible for Lot’s wife to survive being turned into a pillar of salt? Traditionally, essences (or natures) have been thought to help answer such central questions about existence, identity, persistence, and modality. These questions are not only of great philosophical interest, they also are of great interest to society at large. This Handbook surveys the state of the art on essence. Core issues about essence are discussed in 33 chapters, all of them written exclusively for this volume by leading experts.

In this paper I apply the concept of _inter-Model Inconsistency in Set Theory_ (MIST), introduced by Carolin Antos (this volume), to select positions in the current universe-multiverse debate in philosophy of set theory: I reinterpret H. Woodin’s _Ultimate L_, J. D. Hamkins’ multiverse, S.-D. Friedman’s hyperuniverse and the algebraic multiverse as normative strategies to deal with the situation of de facto inconsistency toleration in set theory as described by MIST. In particular, my aim is to situate these positions on the spectrum from inconsistency avoidance to inconsistency toleration. By doing so, I connect a debate in philosophy of set theory with a debate in philosophy of science about the role of inconsistencies in the natural sciences. While there are important differences, like the lack of threatening explosive inferences, I show how specific philosophical positions in the philosophy of set theory can be interpreted as reactions to a state of inconsistency similar to analogous reactions studied in the philosophy of science literature. My hope is that this transfer operation from philosophy of science to mathematics sheds a new light on the current discussion in philosophy of set theory; and that it can help to bring philosophy of mathematics and philosophy of science closer together.