Objective Bayesianism is a methodological theory that is currently applied in statistics, philosophy, artificial intelligence, physics and other sciences. This book develops the formal and philosophical foundations of the theory, at a level accessible to a graduate student with some familiarity with mathematical notation.

The Problem of Iterated Ground is to explain what grounds truths about ground: if Γ grounds φ, what grounds that Γ grounds φ? This paper develops a novel solution to this problem. The basic idea is to connect ground to explanatory arguments. By developing a rigorous account of explanatory arguments we can equip operators for factive and non-factive ground with natural introduction and elimination rules. A satisfactory account of iterated ground falls directly out of the resulting logic: non- factive grounding (...) claims, if true, are zero-grounded in the sense of Fine. (shrink)

Most authors on metaphysical grounding have taken full grounding to be an internal relation in the sense that it's necessary that if the grounds and the grounded both obtain, then the grounds ground the grounded. The negative part of this essay exploits empirical and provably nonparadoxical self-reference to prove conclusively that even immediate full grounding isn't an internal relation in this sense. The positive, second part of this essay uses the notion of a “completely satisfactory explanation” to shed light on (...) the logic of ground in the presence of self-reference. This allows us to develop a satisfactory logic of ground and recover a sense in which grounding is still an internal relation. (shrink)

A collection of essays on rationality - its scope, its limitations and its failures.

I systematically defend a novel account of the grounds for identity and distinctness facts: they are all uniquely zero‐grounded. First, this Null Account is shown to avoid a range of problems facing other accounts: a relation satisfying the Null Account would be an excellent candidate for being the identity relation. Second, a plenitudinist view of relations suggests that there is such a relation. To flesh out this plenitudinist view I sketch a novel framework for expressing real definitions, use this framework (...) to give a definition of identity, and show how the central features of the identity relation can be deduced from this definition. (shrink)

This article explores the nature and theoretical import of a hitherto neglected class of fictions which we term ‘self-involving interactive fictions’. SIIFs are interactive fictions, but they differ from standard examples of interactive fictions by being, in some important sense, about those who consume them. In order to better understand the nature of SIIFs, and the ways in which they differ from other fictions, we focus primarily on the most prominent example of the category: video-game fictions. We argue that appreciating (...) the self-involving nature of video-game fictions is key to understanding various otherwise puzzling phenomena concerning the ways in which consumers respond to them. Video-game fictions are, however, far from being the only extant example of this class; and we suggest that the recent philosophical interest in video games would be better focused on the wider class of self-involving interactive fictions. (shrink)

A logic of grounding where what is grounded can be a collection of truths is a “many-many” logic of ground. The idea that grounding might be irreducibly many-many has recently been suggested by Dasgupta. In this paper I present a range of novel philosophical and logical reasons for being interested in many-many logics of ground. I then show how Fine’s State-Space semantics for the Pure Logic of Ground can be extended to the many-many case, giving rise to the Pure Logic (...) of Many-Many Ground. In the second, more technical, part of the paper, I do two things. First, I present an alternative formalization of plg; this allows us to simplify Fine’s completeness proof for plg. Second, I formalize plmmg using an infinitary sequent calculus and prove that this formalization is sound and complete. (shrink)

Fine (2012) is a pluralist about grounding. He holds that there are three fundamentally distinct notions of grounding: metaphysical, normative, and natural. Berker (2017) argues for monism on the grounds that the pluralist cannot account for certain principles describing how the distinct notions of grounding interact. This paper defends pluralism. By building on work by Fine (2010) and Litland (2015) I show how the pluralist can systematically account for Berker's interaction principles.

The study of intrapersonal economic relations, or economics , is still at the programmatic stage. There is no generally accepted paradigm, or even as well-defined set of problems that constitute it as a subdiscipline within economics. Some questions are, however, emerging as foci of interest for a small but increasing number of writers, not just in economics, but also in psychology and philosophy. The writings of Thomas Schelling on self-management, of George Ainslie on self-control, and of Derik Parfit on personal (...) identity testify to this convergence. (shrink)

Wilhelm has recently shown that widely accepted principles about immediate ground are inconsistent with some principles of propositional identity. This note responds to this inconsistency by developing two ground-theoretic accounts of propositional individuation. On one account some of the grounding principles are incorrect; on the other account, the principles of propositional individuation are incorrect.

In arguments in support of capitalism, the following propositions are sometimes advanced or presupposed: the best life for the individual is one of consumption, understood in a broad sense that includes aesthetic pleasures and entertainment as well as consumption of goods in the ordinary sense; consumption is to be valued because it promotes happiness or welfare, which is the ultimate good; since there are not enough opportunities for consumption to provide satiation for everybody, some principles of distributive justice must be (...) chosen to decide who gets what; the total to be distributed has first to be produced. What is produced depends, among other things, on the motivation and information of the producers. The theory of justice must take account of the fact that different principles of distribution have different effects on motivation and information; economic theory tells us that the motivational and informational consequences of private ownership of the means of production are superior to those of the various forms of collective ownerships. In the traditional controversy over the relative merits of capitalism and economic systems, the focus has been on proposition. In this paper, I consider instead propositions and. Before one can even begin to discuss how values are to be allocated, one must consider what they are – what it is that ought to be valued. I shall argue that at the center of Marxism is a specific conception of the good life as one of active self-realization, rather than passive consumption. (shrink)

In recent years much effort has gone into the study of languages which strengthen the classical first-order predicate calculus in various ways. This effort has been motivated by the desire to find a language which is(I) strong enough to express interesting properties not expressible by the classical language, but(II) still simple enough to yield interesting general results. Languages investigated include second-order logic, weak second-order logic, ω-logic, languages with generalized quantifiers, and infinitary logic.

This paper evaluates the proof-theoretic definition of ground developed by Poggiolesi in a range of recent publications and argues that her proposed definition fails. The paper then outlines an alternative approach where logical consequence relations and the logical operations are defined in terms of ground.

The semeiotic of Charles Sanders Peirce is irreducibly triadic, positing that a sign mediates between the object that determines it and the interpretant that it determines. He eventually holds that each sign has two objects and three interpretants, standardizing quickly on immediate and dynamical for the objects but experimenting with a variety of names for the interpretants. The two most prominent terminologies are immediate/dynamical/final and emotional/energetic/logical, and scholars have long debated how they are related to each other. This paper seeks (...) to shed new light on the matter by reviewing the numerous manuscript drafts where Peirce develops the latter nomenclature while attempting to introduce his pragmatism to a general audience. It then goes on to examine an additional set of interpretants, intentional/effectual/communicational, and shows that the three different trichotomies can be understood as complementary, rather than redundant or conflicting. (shrink)

Could φ’s partially grounding ψ itself be a partial ground for ψ? I show that it follows from commonly accepted principles in the logic of ground that this sometimes happens. It also follows from commonly accepted principles that this never happens. I show that this inconsistency turns on different principles than the puzzles of ground already discussed in the literature, and I propose a way of resolving the inconsistency.

This paper develops a novel theory of abstraction—what we call collective abstraction. The theory solves a notorious problem for noneliminative structuralism. The noneliminative structuralist holds that in addition to various isomorphic systems there is a pure structure that can be abstracted from each of these systems; but existing accounts of abstraction fail for nonrigid systems like the complex numbers. The problem with the existing accounts is that they attempt to define a unique abstraction operation. The theory of collective abstraction instead (...) simultaneously defines a collection of distinct abstraction operations, each of which maps a system to its corresponding pure structure. The theory is precisely formulated in an essentialist language. This allows us to throw new light on the question to what extent structuralists are committed to symmetric dependence. Finally, we apply the theory of collective abstraction to solve a problem about converse relations. (shrink)

Why is it that we cannot legitimately make certain aesthetic assertions – for instance that ‘Guernica is harrowing’ or that ‘The Rite of Spring is strangely beautiful’ – on the basis of testimony alone? In this paper I consider a species of argument intended to demonstrate that the best explanation for the impermissibility of such assertions is that a particular view of the norms of aesthetic belief – pessimism concerning aesthetic testimony – is correct. I begin by outlining the strongest (...) instance of such ‘arguments from assertion’ and demonstrating that it presents a powerful motivation for embracing pessimism; the view that it is illegitimate to form aesthetic beliefs on the basis of testimony alone. I then go on to argue that, appearances notwithstanding, the pessimist’s opponents – optimists concerning aesthetic testimony – are able to provide an explanation for the impermissibility of these assertions which is at least as good as, and in some respects better than, that offered by their pessimist. The explanation I propose draws on some important work on signalling in aesthetics, by Denis Dutton and others, to argue that the problem with such assertions is closely parallel to the problem Dutton claims is generated by forgeries. Those making such assertions misrepresent a piece of aesthetic labour as their own, when, in fact, it is the work of another. I also explore the wider implications of this view for debates in aesthetic epistemology and beyond. (shrink)

Grounding is bicollective if it is possible for some truths δ,δ,... to be grounded in the some truths γ,γ,... without its being the case that each δi is grounded in some subcollection of γ,γ,.... In this paper I show how to do develop a hypergraph-theoretic account of bicollective ground, taking the notion of immediate ground as basic. I also indicate how bicollective ground helps with formulating mathematical structuralism.

Although he is best known as the founder of pragmatism, the name that Charles Sanders Peirce prefers to use for his comprehensive system of thought is "synechism" because the principle of continuity is its central thesis. This paper arranges and summarizes numerous quotations and citations from his voluminous writings to formalize and explicate his distinctive mathematical conceptions of hyperbolic and topical continuity, both of which are derived from the direct observation of time as their paradigmatic manifestation, and then apply them (...) in normative science and metaphysics, especially logic as semeiotic and cosmology. The resulting conclusion is that the intelligibility of the universe is plausibly explained by conceiving it as one immense sign, a vast inferential process: a semiosic continuum whose connected constituent signs are indefinite until deliberately marked off, with God the Creator as its overall dynamical object in the infinite past and God completely revealed as its overall final interpretant in the infinite future. (shrink)

Peirce is best known as the founder of pragmatism, but his dissatisfaction with how others understood and appropriated it prompted him to rename his own doctrine “pragmaticism” and to compose several variants of his original maxim defining it, as well as numerous restatements and elaborations. This paper presents an extensive selection of such formulations, followed by analysis and commentary demonstrating that for Peirce the ultimate meaning of an intellectual concept is properly expressed as a conditional proposition about the deliberate, self-controlled (...) conduct of its interpreters, not the law-governed behavior of its object. (shrink)

Unusability pessimism has recently emerged as an appealing new option for pessimists about aesthetic testimony—those who deny the legitimacy of forming aesthetic beliefs on the basis of testimony. Unusability pessimists argue that we should reject the traditional pessimistic stance that knowledge of aesthetic matters is unavailable via testimony in favour of the view that while such knowledge is available to us, it is unusable. This unusability stems from the fact that accepting such testimony would violate an important non-epistemic norm of (...) belief formation. In this article I present an objection to unusability pessimism and argue that Robert Hopkins, the view's most prominent defender, fails to motivate adequately the claim that there are such non-epistemic belief norms. The cases which putatively legitimize usability norms can be explained by appeal to more familiar norm types: epistemic norms of belief formation, and non-epistemic norms which govern action other than belief formation. The intent of this article is not primarily negative, however, and I will also argue that understanding why the unusability position fails helps us to identify a promising new direction for the pessimist's opponents who wish to defend the legitimacy of forming aesthetic beliefs on the basis of testimony. (shrink)

Bayesian probability is normally defined over a fixed language or eventspace. But in practice language is susceptible to change, and thequestion naturally arises as to how Bayesian degrees of belief shouldchange as language changes. I argue here that this question poses aserious challenge to Bayesianism. The Bayesian may be able to meet thischallenge however, and I outline a practical method for changing degreesof belief over changes in finite propositional languages.

Using only uncontentious principles from the logic of ground I construct an infinitely descending chain of ground without a lower bound. I then compare the construction to the constructions due to Dixon and Rabin and Rabern.

Biomedical innovations are making possible the enhancement of human capabilities. There are two philosophical stances on the role that medicine should play in this respect. On the one hand, naturalism rejects every medical intervention that goes beyond preventing and treating disease. On the other hand, welfarism advocates enhancements that foster subjective well-being. We will show that both positions have considerable shortcomings. Consequently, we will introduce a third characterization in which therapies and enhancements can be reconciled with the legitimate objectives of (...) medicine inasmuch as they improve the capabilities that enable the freedom to pursue personal well-being. (shrink)

The term “virtual reality” was first coined by Antonin Artaud to describe a value-adding characteristic of certain types of theatrical performances. The expression has more recently come to refer to a broad range of incipient digital technologies that many current philosophers regard as a serious threat to human autonomy and well-being. Their concerns, which are formulated most succinctly in “brain in a vat”-type thought experiments and in Robert Nozick's famous “experience machine” argument, reflect a fundamental misunderstanding of the way that (...) such technologies would probably have to work. They also considerably underestimate the positive contributions that virtual reality technologies could make to the growth of human knowledge. Here, we examine and critique Nozick's claim that no reasonable person would want to plug into his hypothetical experience machine in light of a broadly enactivist understanding of how future VR technologies might be expected to function. We then sketch out a tentative theory of the phenomenon of truth in fiction, in order to characterize some of the distinct epistemic opportunities that VR technologies promise to provide. (shrink)

Debates over adaptationism can be clarified and partially resolved by careful consideration of the ‘grain’ at which evolutionary processes are described. The framework of ‘adaptive landscapes’ can be used to illustrate and facilitate this investigation. We argue that natural selection may have special status at an intermediate grain of analysis of evolutionary processes. The cases of sickle-cell disease and genomic imprinting are used as case studies.

Standard accounts of semantics for counterfactuals confront the true–true problem: when the antecedent and consequent of a counterfactual are both actually true, the counterfactual is automatically true. This problem presents a challenge to safety-based accounts of knowledge. In this paper, drawing on work by Angelika Kratzer, Alan Penczek, and Duncan Pritchard, we propose a revised understanding of semantics for counterfactuals utilizing machinery from generalized quantifier theory which enables safety theorists to meet the challenge of the true–true problem.

When a proposition is established, it can be taken as evidence for other propositions. Can the Bayesian theory of rational belief and action provide an account of establishing? I argue that it can, but only if the Bayesian is willing to endorse objective constraints on both probabilities and utilities, and willing to deny that it is rationally permissible to defer wholesale to expert opinion. I develop a new account of deference that accommodates this latter requirement.