Carl Hoefer

Classical statistical mechanics posits probabilities for various events to occur, and these probabilities seem to be objective chances. This does not seem to sit well with the fact that the theory’s time evolution is deterministic. We argue that the tension between the two is only apparent. We present a theory of Humean objective chance and show that chances thus understood are compatible with underlying determinism and provide an interpretation of the probabilities we find in Boltzmannian statistical mechanics.

In his contribution to this volume, Christopher Meacham identifies a possibly serious defect of the pragmatic Humean approach to laws and chance, compared to the more fundamentalist/reductionist approaches of Lewis and Loewer: a potential inconsistency in the credences that rational agents are advised to have, when two or more different objective chances are ascribed to the same event by distinct parts of the pragmatist’s chance theory. This chapter discusses Meacham’s objections, some of which apply to Hoefer’s approach to objective chance, and some of which apply to Callender and Cohen’s Better Best System account of laws. In the course of defending Hoefer’s account of chance from the inconsistency objection, the chapter also discusses some contentious issues regarding how we should understand the Principal Principle, and in particular whether it should include an ‘admissibility clause’.

Since the death of strong reductionism, philosophers of science have expanded the horizons of their understandings of the physical, mental, and social worlds, and the complex relations among them. To give one interesting example, John Dupre has endorsed a notion of downward causation: ‘higher-level’ events causing events at a ‘lower’ ontological level. For example, my intention to type the letter ‘t’ causes the particular motions experienced by all the atoms in my left forefinger as I type it. The proper explanation of the motions of an atom at the tip of my forefinger primarily involves my intentions, rather than the immediately preceding motions of other nearby atoms, or any other such particle–level events.

Our main aim in this paper is to evaluate from a critical historical-philosophical standpoint the intellectualIntellectual origins of ‘Landauer’s principlePrinciple’, a thesis formulated in 1961 by the IBM researcher Rolf Landauer[aut]Landauer, Rolf. He asserted that any physicalPhysical implementation of a logically irreversibleIrreversible operation such as erasing a bit of information leads to an entropy increase in the systemSystem computing that operation. Contrary to the popular narratives from the thermodynamicsThermodynamics of computation about the genesis of Landauer’s principle, we argue that this ideaIdeas was influenced, firstly, by Léon Brillouin’s[aut]Brillouin, Leon Negentropy principle, theoretically connecting information and entropy. Secondly, Landauer found in John von Neumann’s[aut]Neumann, John, vonideasIdeas in 1949 the path to connect informational processesProcess and thermal effects through the logical irreversibilityIrreversibility of computational operations. Interestingly, both Brillouin and von Neumann also gave general and ill-defined formulations of this ideaIdeas previous to the work of Landauer. Finally, alongside these two main intellectualIntellectual sources one should include, complementing historiographic proposals such as Wright, the influence of the potential double-well model of the IBM researcher John Swanson in developing a concrete model to apply this thesis. Finally, we defend reconceiving the intellectual genesis of Landauer’s principlePrinciple as a direct historical heir to a rich multiplicity of physical, informational, and computational trends of thought during the 1950s.

The authors survey some debates about the nature and structure of physical theories and about the connections between our physical theories and naturalized metaphysics. The discussion is organized around an “ideal view” of physical theories and criticisms that can be raised against it. This view includes controversial commitments regarding the best analysis of physical modalities and intertheory relations. The authors consider the case in favor of taking laws as the primary modal notion, discussing objections related to alleged violations of the laws, the apparent need to appeal to causality, and the status of probability. The “ideal view” includes a commitment that fundamental physical theories are explanatorily sufficient. The authors discuss several challenges to recovering the manifest image from fundamental physics, along with a distinct challenge to reductionism based on acknowledging the contributions of less fundamental theories in physical explanations.

A widespread view among physicists is that Bell’s theorem rests on an implicit assumption of “classicality,” in addition to locality. According to this understanding, the violation of Bell’s inequalities poses no challenge to locality, but simply reinforces the fact that quantum mechanics is not classical. The paper provides a critical analysis of this view. First we characterize the notion of classicality in probabilistic terms. We argue that classicality thus construed has nothing to do with the validity of classical physics, nor of classical probability theory, contrary to what many believe. At the same time, we show that the probabilistic notion of classicality is not an additional premise of Bell’s theorem, but a mathematical corollary of locality in conjunction with the standard auxiliary assumptions of Bell. Accordingly, any theory that claims to get around the derivation of Bell’s inequalities by giving up classicality, in fact has to give up one of those standard assumptions. As an illustration of this, we look at two recent interpretations of quantum mechanics, Reinhard Werner’s operational quantum mechanics and Robert Griffiths’ consistent histories approach, that are claimed to be local and non-classical, and identify which of the standard assumptions of Bell’s theorem each of them is forced to give up. We claim that while in operational quantum mechanics the Common Cause Principle is violated, the consistent histories approach is conspiratorial. Finally, we relate these two options to the idea of realism, a notion that is also often identified as an implicit assumption of Bell’s theorem.

One currently popular view about the nature of objective probabilities, or objective chances, is that they – or some of them, at least – are primitive features of the physical world, not reducible to anything else nor explicable in terms of frequencies, degrees of belief, or anything else. In this paper I explore the question of what the semantic content of primitive chance claims could be. Every attempt I look at to supply such content either comes up empty-handed, or begs important questions against the skeptic who doubts the meaningfulness of primitive chance claims. In the second half of the paper I show that, by contrast, there are clear, and clearly contentful, ways to understand objective chance claims if we ground them on deterministic physical underpinnings.

Scientific realists often say that there should be belief in the approximate truth of ‘our best scientific theories.’ It is hard to hear the phrase ‘our best scientific theories’ without thinking of quantum mechanics and quantum field theories. But as numerous chapters in this collection make clear, it is unclear that some experts even know how to make sense of being a realist about quantum theories. They provide recipes for calculating incredibly precise predictions for observations, but beyond the recipes, they do not seem to offer a clear-cut or unambiguous picture of what physical reality is like at the fundamental level. After giving an overview of the problems that beset any attempt to believe in the truth or approximate truth of quantum theories, Chapter 2 turns to the question of how to protect scientific realism from the ills of the quantum. The aim is to show that it is possible to quarantine the worst of those ills, freeing us to adopt a robustly realistic attitude toward many other extremely successful areas of contemporary science, such as (parts of) geology, microbiology, and chemistry. The quarantine barrier may be imperfect and permeable in places, but is strong enough (the chapter argues) to help the cause of scientific realism.

Biomedical research, especially pharmaceutical research, has been criticised for engaging in practices that lead to over-estimations of the effectiveness of medical treatments. A central issue concerns the reporting of absolute and relative measures of medical effectiveness. In this paper we critically examine proposals made by Jacob Stegenga to (a) give priority to the reporting of absolute measures over relative measures, and (b) downgrade the measures of effectiveness (effect sizes) of the treatments tested in clinical trials (Stegenga, 2015a). After exposing significant flaws in a central case study used by Stegenga to bolster his first proposal (a), we go on to argue that neither of these proposals is defensible (a or b). We defend the practice, in line with the New England Journal of Medicine, of reporting both absolute and relative measures whenever feasible.

In this paper we critically review Correia’s and Rosenkranz’s Nothing to Come. A Defence of the Growing Block Theory of Time, published by Springer in 2018. By taking into account the essential reliance of the book on tense logic, we bring out the existence of a conflict between their logical axioms, that presuppose truth bivalence even for statements concerning future contingents, and the principle of groundedness that they also advocate. According to this principle, a proposition Q is now groundedly true as long as sometimes in the future it will be the case that there exists something that makes Q true. However, if the events that occur in 2060 do not exist unrestrictedly (for us, here in 2021), what, in reality, can possibly ground the truth (or falsity) of Q? In the second part of the paper, we concentrate on some conceptual difficulties raised by their brilliant attempt to adapt the growing block view of reality to a relativistic setting, based on what they call bow-tie presentism, according to which for each spacetime point s only s plus the spacelike-related region with respect to s exists. By extending temporal logic into a relativity-friendly spatiotemporal logic, we conclude by noting that Correia and Rosenkranz’s Nothing to Come makes very important strides in showing that there are technical ways to develop the growing block of reality into an ontology that coheres with relativity theories perfectly well, while retaining most of the distinctive content of classical growing block theory.

We offer a novel argument for one-boxing in Newcomb’s Problem. The intentional states of a rational person are psychologically coherent across time, and rational decisions are made against this backdrop. We compare this coherence constraint with a golf swing, which to be effective must include a follow-through after the ball is in flight. Decisions, like golf swings, are extended processes, and their coherence with other psychological states of a player in the Newcomb scenario links her choice with the way she is predicted in a common cause structure. As a result, the standard argument for two-boxing is mistaken.

This paper continues the defense of a version of scientific realism, Tautological Scientific Realism, that rests on the claim that, excluding some areas of fundamental physics about which doubts are entirely justified, many areas of contemporary science cannot be coherently imagined to be false other than via postulation of radically skeptical scenarios, which are not relevant to the realism debate in philosophy of science. In this paper we discuss, specifically, the threats of meaning change and reference failure associated with the Kuhnian tradition, which depend on a descriptivist approach to meaning, and we argue that descriptivism is not the right account of the meaning and reference of theoretical terms. We suggest that an account along the lines of the causal-historical theory of reference provides a more faithful picture of how terms for unobservable theoretical entities and properties come to refer; we argue that this picture works particularly well for TSR. In the last section we discuss how our account raises concerns specifically for perspectival forms of scientific realism.

Nancy Cartwright is one of the most distinguished and influential contemporary philosophers of science. Despite the profound impact of her work, there is neither a systematic exposition of Cartwright’s philosophy of science nor a collection of articles that contains in-depth discussions of the major themes of her philosophy. This book is devoted to a critical assessment of Cartwright’s philosophy of science and contains contributions from Cartwright's champions and critics. Broken into three parts, the book begins by addressing Cartwright's views on the practice of model building in science and the question of how models represent the world before moving on to a detailed discussion of methodologically and metaphysically challenging problems. Finally, the book addresses Cartwright's original attempts to clarify profound questions concerning the metaphysics of science. With contributions from leading scholars, such as Ronald N. Giere and Paul Teller, this unique volume will be extremely useful to philosophers of science the world over.

In recent years attacks on the Kripke-Putnam approach to natural kinds and natural kind terms have proliferated. In a recent paper, Häggqvist and Wikforss (The British Journal for the Philosophy of Science, 1–23, 2017) attack the once-dominant essentialist account of natural kinds. Häggqvist & Wikforss also suggest that it is time to return to some sort of cluster-based descriptivist semantics for natural kind terms, thus targeting both the metaphysical and semantic tenets that underpin the Kripke-Putnam approach. In our paper we want to challenge both parts of Häggqvist and Wikforss’ project. We will argue that the anti-essentialist considerations and arguments they raise against the Kripke-Putnam view are far from compelling in some cases, and certainly not decisive against a reasonable form of the view. On the semantic side, although Häggqvist and Wikforss give few details about what a viable cluster-based descriptivist theory should look like, we will argue that one can already see the approach to be a non-starter. Ignorance and error arguments of the kinds provided by Kripke and Putnam continue to be decisive objections. The only way we can see to save the cluster descriptivist approach is to make the essential properties postulated by Kripke and Putnam become essential features of the descriptive cluster. But this makes the success of the approach parasitic on the correctness of the Kripke-Putnam view.

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

The paper investigates the kind of dependence relation that best portrays Machian frame-dragging in general relativity. The question is tricky because frame-dragging relates local inertial frames to distant distributions of matter in a time-independent way, thus establishing some sort of non-local link between the two. For this reason, a plain causal interpretation of frame-dragging faces huge challenges. The paper will shed light on the issue by using a generalized structural equation model analysis in terms of manipulationist counterfactuals recently applied in the context of metaphysical enquiry by Schaffer (2016) and Wilson (2017). The verdict of the analysis will be that frame-dragging is best understood in terms of a novel type of dependence relation that is half-way between causation and grounding.