It is often claimed that the greatest value of the Bayesian framework in cognitive science consists in its unifying power. Several Bayesian cognitive scientists assume that unification is obviously linked to explanatory power. But this link is not obvious, as unification in science is a heterogeneous notion, which may have little to do with explanation. While a crucial feature of most adequate explanations in cognitive science is that they reveal aspects of the causal mechanism that produces the phenomenon to be (...) explained, the kind of unification afforded by the Bayesian framework to cognitive science does not necessarily reveal aspects of a mechanism. Bayesian unification, nonetheless, can place fruitful constraints on causal–mechanical explanation. 1 Introduction2 What a Great Many Phenomena Bayesian Decision Theory Can Model3 The Case of Information Integration4 How Do Bayesian Models Unify?5 Bayesian Unification: What Constraints Are There on Mechanistic Explanation?5.1 Unification constrains mechanism discovery5.2 Unification constrains the identification of relevant mechanistic factors5.3 Unification constrains confirmation of competitive mechanistic models6 ConclusionAppendix. (shrink)

One stark difference between the past and the future lies in our ability to shape the future in a way in which we are unable to shape the past. This paper investigates what kind of beliefs about the future serve as premises in our reasoning about how to act. If we think about belief in terms of agents representing the world, we cannot lose sight of the fact that agents are part of, and shape, the same world they represent. Beliefs (...) about the future appear to have a circularity about them: on the one hand, they serve as premises for deciding what we will do. On the other hand, what we decide we will do determines what we believe about the future. I argue that beliefs in future-directed counterfactuals play a central role in our practical reasoning and in how we conceptualize the actual future. I defend a robust distinction between future-directed counterfactuals and future-directed indicatives, and, contra Keith DeRose (2010), argue that it is future-directed counterfactuals that we use in deliberation about how to act. I argue that we construe the actual future in hypothetical terms and dependent on what we do now, in contrast to how we construe the actual past. This asymmetry in our belief content about the past versus the future fits well with an account of the open future in terms of counterfactual dependence. (shrink)

Belief polarization is said to occur when two people respond to the same evidence by updating their beliefs in opposite directions. This response is considered to be “irrational” because it involves contrary updating, a form of belief updating that appears to violate normatively optimal responding, as for example dictated by Bayes' theorem. In light of much evidence that people are capable of normatively optimal behavior, belief polarization presents a puzzling exception. We show that Bayesian networks, or Bayes nets, can simulate (...) rational belief updating. When fit to experimental data, Bayes nets can help identify the factors that contribute to polarization. We present a study into belief updating concerning the reality of climate change in response to information about the scientific consensus on anthropogenic global warming. The study used representative samples of Australian and U.S. participants. Among Australians, consensus information partially neutralized the influence of worldview, with free-market supporters showing a greater increase in acceptance of human-caused global warming relative to free-market opponents. In contrast, while consensus information overall had a positive effect on perceived consensus among U.S. participants, there was a reduction in perceived consensus and acceptance of human-caused global warming for strong supporters of unregulated free markets. Fitting a Bayes net model to the data indicated that under a Bayesian framework, free-market support is a significant driver of beliefs about climate change and trust in climate scientists. Further, active distrust of climate scientists among a small number of U.S. conservatives drives contrary updating in response to consensus information among this particular group. (shrink)

This comprehensive new book introduces the core history of phenomenology and assesses its relevance to contemporary psychology, philosophy of mind, and cognitive science. From critiques of artificial intelligence research programs to ongoing work on embodiment and enactivism, the authors trace how phenomenology has produced a valuable framework for analyzing cognition and perception, whose impact on contemporary psychological and scientific research, and philosophical debates continues to grow. The first part of _An Introduction to Phenomenology_ is an extended overview of the history (...) and development of phenomenology, looking at its key thinkers, focusing particularly on Husserl, Heidegger and Merleau-Ponty, as well as its cultural and intellectual precursors. In the second half Chemero and Käufer turn their attention to the contemporary interpretations and uses of phenomenology in cognitive science, showing that phenomenology is a living source of inspiration in contemporary interdisciplinary studies of the mind. Käufer and Chemero have written a clear, jargon-free account of phenomenology, providing abundant examples and anecdotes to illustrate and to entertain. This book is an ideal introduction to phenomenology and cognitive science for the uninitiated, as well as for philosophy and psychology students keen to deepen their knowledge. (shrink)

This paper focuses on the question of how to resolve disagreement and uses the Lehrer-Wagner model as a formal tool for investigating consensual decision-making. The main result consists in a general definition of when agents treat each other as epistemic peers (Kelly 2005; Elga 2007), and a theorem vindicating the “equal weight view” to resolve disagreement among epistemic peers. We apply our findings to an analysis of the impact of social network structures on group deliberation processes, and we demonstrate their (...) stability with the help of numerical simulations. (shrink)

Bayes nets are a powerful tool for researchers in statistics and artificial intelligence. This chapter demonstrates that they are also of much use for philosophers and psychologists interested in (Bayesian) rationality. To do so, we outline the general methodology of Bayes nets modeling in rationality research and illustrate it with several examples from the philosophy and psychology of reasoning and argumentation. Along the way, we discuss the normative foundations of Bayes nets modeling and address some of the methodological problems it (...) raises. (shrink)

In the past decade well-designed research studies have shown that the practice of collaborative philosophical inquiry in schools can have marked cognitive and social benefits. Student academic performance improves, and so too does the social dimension of schooling. These findings are timely, as many countries in Asia and the Pacific are now contemplating introducing Philosophy into their curricula. This paper gives a brief history of collaborative philosophical inquiry before surveying the evidence as to its effectiveness. The evidence is canvassed under (...) two categories: schooling and thinking skills; and schooling, socialisation and values. In both categories there is clear evidence that even short-term teaching of collaborative philosophical inquiry has marked positive effects on students. The paper concludes with suggestions for further research and a final claim that the presently-available research evidence is strong enough to warrant implementing collaborative philosophical inquiry as part of a long-term policy. (shrink)

The reported birth of genetically modified twins in late 2018 has given new fuel to debates about the ethics of germline genome editing (GGE). There is a broad consensus among stakeholders that clinical uses of GGE should be temporarily banned as the technology is not yet deemed safe for use in humans. However, the idea of a complete ban is dismissed by many based on the expectation that more research will eventually allow scientists to make the technology safe without having (...) to put humans at risk first. In this article, I will analyse this assumption and argue that it is undermined by recent developments in the postgenomic life sciences. In particular, I will argue that in a postgenomic view of germline editing a complete ban on specific uses of the technology is warranted, because the research needed to assess the safety of these interventions would not be morally defensible. (shrink)

Effective field theories have been a very popular tool in quantum physics for almost two decades. And there are good reasons for this. I will argue that effective field theories share many of the advantages of both fundamental theories and phenomenological models, while avoiding their respective shortcomings. They are, for example, flexible enough to cover a wide range of phenomena, and concrete enough to provide a detailed story of the specific mechanisms at work at a given energy scale. So will (...) all of physics eventually converge on effective field theories? This paper argues that good scientific research can be characterised by a fruitful interaction between fundamental theories, phenomenological models and effective field theories. All of them have their appropriate functions in the research process, and all of them are indispensable. They complement each other and hang together in a coherent way which I shall characterise in some detail. To illustrate all this I will present a case study from nuclear and particle physics. The resulting view about scientific theorising is inherently pluralistic, and has implications for the debates about reductionism and scientific explanation. (shrink)

There has been much concern with the abundance of misinformation in public discourse. Although misinformation has always played a role in political debate, its character has shifted from support fo...

De se attitudes seem to play a special role in action and cognition. This raises a challenge to the traditional way in which mental attitudes have been understood. In this chapter, we review the case for thinking that de se attitudes require special theoretical treatment and discuss various ways in which the traditional theory can be modified to accommodate de se attitudes.

Scientific theories are used for a variety of purposes. For example, physical theories such as classical mechanics and electrodynamics have important applications in engineering and technology, and we trust that this results in useful machines, stable bridges, and the like. Similarly, theories such as quantum mechanics and relativity theory have many applications as well. Beyond that, these theories provide us with an understanding of the world and address fundamental questions about space, time, and matter. Here we trust that the answers (...) scientific theories give are reliable and that we have good reason to believe that the features of the world are similar to what the theories say about them. But why do we trust scientific theories, and what counts as evidence in favor of them? (shrink)

Will it rain tomorrow? Will there be a sea battle tomorrow? Will my death be painful? Wondering about the future plays a central role in our cognitive lives. It is integral to our inquiries, our planning, our hopes, and our fears. The aim of this paper is to consider various accounts of future contingents and the implications that they have for wondering about the future. I argue that reflecting on the nature of wondering about the future supports an Ockhamist account (...) of future contingents according to which many of them are true. Alternative accounts which maintain that no future contingents are true, either by claiming that they are all false or by claiming that they are neither true nor false, face difficulties concerning why it is appropriate to wonder about them. Reflecting on wondering in general, and wondering about the future in particular, suggests that in wondering how the future will go, we implicitly assume that there is a determinate fact of the matter. After presenting an attractive account of interrogative attitudes that has been recently proposed by Jane Friedman and outlining some norms governing wondering, I argue that all accounts of future contingents except Ockhamism face difficulties concerning why it is appropriate to wonder about them. (shrink)

The authors challenge the reigning “causal power framework” as an explanation for whether a particular outcome was actually caused by a specific potential cause. They test a new measure of causal attribution in two experiments by embedding the measure within the Structure Induction model of Singular Causation (SISC, Stephan & Waldmann, 2016).

In this discussion note, we explain how to relax some of the standard assumptions made in Garber-style solutions to the Problem of Old Evidence. The result is a more general and explanatory Bayesian approach.

Under the standard modal explication of consequence, a conclusion is a consequence of some premises just in case necessarily, if the latter are true, so is the former. Notoriously, this explication yields some results that at first glance are counter-intuitive. In particular, a necessary truth is a consequence of arbitrary premises, and premises that cannot all be true together entail arbitrary conclusions. In his paper ‘On Ground and Consequence’ (Synthese, 2021), Benjamin Schnieder introduces a novel notion of web consequence, defined (...) on the basis of the concept of ground, which, he argues, fits our intuitive conception better. Building on his idea, the present paper examines the concept of web consequence in more detail. In particular, I provide three alternative, and simpler semantic characterizations of Schnieder’s propositional logic of web consequence, two within a form of truthmaker semantics, one within a many-valued setting. I then consider some natural variations on that logic and establish their connections to well-known subclassical logics such as FDE, $$\hbox {K}_3$$ K 3, and LP. Finally, I provide sound and complete tableaux-based proof systems for each of the logics of web consequence so obtained. (shrink)

Anthropology of Consciousness, Volume 32, Issue 2, Page 129-153, Autumn 2021.

What is the relationship between Frege’s puzzle and the puzzle of the de se? An increasingly influential view claims that the de se puzzle is merely an instance of Frege’s puzzle and that the idea that de se attitudes pose a distinctive theoretical challenge rests on a myth. Here we argue that this view is misguided. There are important differences between the two puzzles. First, unlike Frege puzzle cases, de se puzzle cases involve unshareable Fregean senses. Second, unlike Frege puzzle (...) cases, de se puzzle cases cannot be resolved by objective information alone. Further, there seem to be pure cases of each puzzle: instances of the de se puzzle which do not have a Fregean structure, and instances of Frege’s puzzle, which do not involve de se attitudes. We conclude that the two puzzles are fundamentally different and that the traditional theory of attitudes needs to be amended. (shrink)

In the Groundwork of the Metaphysics of Morals, Kant explains a perfect duty as one that “admits no exception in favor of inclination”. An imperfect duty must then, in turn, be one which does admit such exceptions. However, according to Kant, all duties are valid without exception, and so there has been broad agreement among Kantians and Kant interpreters from the beginning that perfect duties cannot be characterized by exceptionless validity. I would thus like to argue in favor of a (...) different reading of Kant’s explanation. My thesis is that he uses the term ‘exception’ in quite different ways, as can be documented, for instance, in the Metaphysics of Morals and the Critique of Pure Reason. The term then has another meaning, and this is also the case in the passage in question in the Groundwork. (shrink)

Conditionals pervade every aspect of our thinking, from the mundane and everyday such as ‘if you eat too much cheese, you will have nightmares’ to the most fundamental concerns as in ‘if global warming isn’t halted, sea levels will rise dramatically’. Many decades of research have focussed on the semantics of conditionals and how people reason from conditionals in everyday life. Here it has been rather overlooked how we come to such conditionals in the first place. In many cases, they (...) are learned through testimony: someone warns us about the ill-effects of cheese. Any full account of the conditional must consequently incorporate such learning. Here, we provide a new formal account of belief change in response to a testimonial conditional. (shrink)

In Nothing to Come, Fabrice Correia and Sven Rosenkranz provide a sophisticated, compelling, and thoroughly defended account of the growing block theory. This note critically evaluates two aspects of this account. First, it evaluates Correia and Rosenkranz’s attempt at providing a grounding principle for future truths and argues that this principle fails to make progress in explaining why future truths are true. Second, it evaluates Correia and Rosenkranz’s construal of the open future arguing that the asymmetry in openness with respect (...) to the past and future is not plausibly understood in terms of determinism and indeterminism, and in the final section, it evaluates their claim that a growing block theorist is able to maintain that the future is open in a stronger sense than the block theorist. (shrink)

Models are of central importance in many scientific contexts. The roles the MIT bag model of the nucleon, the billiard ball model of a gas, the Bohr model of the atom, the Gaussian-chain model of a polymer, the Lorenz model of the atmosphere, the Lotka- Volterra model of predator-prey interaction, agent-based and evolutionary models of social interaction, or general equilibrium models of markets play in their respective domains are cases in point.

Conditionals and conditional reasoning have been a long-standing focus of research across a number of disciplines, ranging from psychology through linguistics to philosophy. But almost no work has concerned itself with the question of how hearing or reading a conditional changes our beliefs. Given that we acquire much—perhaps most—of what we believe through the testimony of others, the simple matter of acquiring conditionals via others’ assertion of a conditional seems integral to any full understanding of the conditional and conditional reasoning. (...) In this paper we detail a number of basic intuitions about how beliefs might change in response to a conditional being uttered, and show how these are backed by behavioral data. In the remainder of the paper, we then show how these deceptively simple phenomena pose a fundamental challenge to present theoretical accounts of the conditional and conditional reasoning – a challenge which no account presently fully meets. (shrink)

The relation of global supervenience is widely appealed to in philosophy. In slogan form, it is explained as follows: a class of properties A supervenes on a class of properties B if no two worlds differ in the distribution of A-properties without differing in the distribution of B-properties. It turns out, though, that there are several ways to cash out that slogan. Three different proposals have been discussed in the literature. In this paper, I argue that none of them is (...) adequate. Furthermore, I present a puzzle that reveals a tension in our concept of global supervenience. (shrink)

Plastids and mitochondria arose through endosymbiotic acquisition of formerly free-living bacteria. During more than a billion years of subsequent concerted evolution, the three genomes of plant cells have undergone dramatic structural changes to optimize the expression of the compartmentalized genetic material and to fine-tune the communication between the nucleus and the organelles. The chimeric composition of many multiprotein complexes in plastids and mitochondria (one part of the subunits being nuclear encoded and another one being encoded in the organellar genome) provides (...) a paradigm for co-evolution at the cellular level. In this paper, we discuss the co-evolution of nuclear and organellar genomes in the context of environmental adaptation in species and populations. We highlight emerging genetic model systems and new experimental approaches that are particularly suitable to elucidate the molecular basis of co-adaptation processes and describe how nuclear-cytoplasmic co-evolution can cause genetic incompatibilities that contribute to the establishment of hybridization barriers, ultimately leading to the formation of new species. (shrink)

We often care not just whether an account of some subject matter is correct, but also whether it is complete—the whole truth, as we might say. This chapter criticizes extant intensional explications of the notion of a whole truth by showing that they yield implausible results in an important range of cases. The difficulty is traced to the inability of an intensional framework to adequately capture constraints of relevance imposed by an intuitive understanding of the whole truth. I go on (...) to develop and defend a novel account of what it is for a truth P to be the whole truth with respect to a subject matter: roughly speaking, it is for every fact pertaining to the subject matter to be relevant to making P true, or equivalently, for P to relevantly entail every truth pertaining to the subject matter. The proposal is formally spelled out within the framework of truthmaker semantics as developed by Kit Fine in a series of recent publications. As part of this, a novel, truthmaker-based semantics for the totality operator ‘...and that’s it’ is sketched and argued to be superior to previous intensional accounts. (shrink)

This paper is an essay review of Steven French and Harmke Kamminga (eds.), Correspondence, Invariance and Heuristics. Essays in Honour of Heinz Post (Dordrecht: Kluwer, 1993). I distinguish a varity of correspondence relations between scientific theories (exemplified by cases from the book under review) and examine how one can make sense of the the prevailing continuity in scientific theorizing.

Say that two sentences are ground-theoretically equivalent iff they are interchangeable salva veritate in grounding contexts. Notoriously, ground-theoretic equivalence is a hyperintensional matter: even logically equivalent sentences may fail to be interchangeable in grounding contexts. Still, there seem to be some substantive, general principles of ground-theoretic equivalence. For example, it seems plausible that any sentences of the form A∧B\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$A \wedge B$$\end{document} and B∧A\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$B (...) \wedge A$$\end{document} are ground-theoretically equivalent. What, then, are in general the conditions for two sentences to stand in the relation of ground-theoretic equivalence, and what are the logical features of that relation? This paper develops and defends an answer to these questions based on the mode-ified truthmaker theory of content presented in my recent paper ‘Towards a theory of ground-theoretic content’ :785–814, 2018). (shrink)

An argument with roots in ancient Greek philosophy claims that only humans are capable of a certain class of thought termed conceptual, as opposed to perceptual thought, which is common to humans, the higher animals, and some machines. We outline the most detailed modern version of this argument due to Mortimer Adler, who in the 1960s argued for the uniqueness of the human power of conceptual thought. He also admitted that if conceptual thought were ever manifested by machines, such an (...) achievement would contradict his conclusion. We revisit Adler’s criterion in the light of the past five decades of artificial-intelligence research, and refine it in view of the classical definitions of perceptual and conceptual thought. We then examine two well-publicized examples of creative works produced by AI systems and show that evidence for conceptual thought appears to be lacking in them. Although clearer evidence for conceptual thought on the part of AI systems may arise in the near future, especially if the global neuronal workspace theory of consciousness prevails over its rival, integrated information theory, the question of whether AI systems can engage in conceptual thought appears to be still open. (shrink)

The parts-based engineering approach in synthetic biology aims to create pre-characterised biological parts that can be used for the rational design of novel functional systems. Given the context-sensitivity of biological entities, a key question synthetic biologists have to address is what properties these parts should have so that they give a predictable output even when they are used in different contexts. In the first part of this paper I will analyse some of the answers that synthetic biologists have given to (...) this question and claim that the focus of these answers on parts and their properties does not allow us to tackle the problem of context-sensitivity. In the second part of the paper, I will argue that we might have to abandon the notions of parts and their properties in order to understand how independence in biology could be achieved. Using Robert Cummins’ account of functional analysis, I will then develop the notion of a capacity and its condition space and show how these notions can help to tackle the problem of context-sensitivity in biology. (shrink)

RNA is central to the COVID-19 pandemic—it shapes how the SARS Coronavirus 2 (SARS-CoV-2) behaves, and how researchers investigate and fight it. However, RNA has received relatively little attention in the history and philosophy of the life sciences. By analysing RNA biology in more detail, philosophers and historians of science could gain new and powerful tools to assess the current pandemic, and the biological sciences more generally.

A lot of research has recently been done on the topic of ground, and in particular on the logic of ground. According to a broad consensus in that debate, ground is hyperintensional in the sense that even logically equivalent truths may differ with respect to what grounds them, and what they ground. This renders pressing the question of what we may take to be the ground-theoretic content of a true statement, i.e. that aspect of the statement’s overall content to which (...) ground is sensitive. I propose a novel answer to this question, namely that ground tracks how, rather than just by what, a statement is made true. I develop that answer in the form of a formal theory of ground-theoretic content and show how the resulting framework may be used to articulate plausible theories of ground, including in particular a popular account of the grounds of truth-functionally complex truths that has proved difficult to accommodate on alternative views of content. (shrink)

Belief revision theories standardly endorse a principle of intensionality to the effect that ideal doxastic agents do not discriminate between pieces of information that are equivalent within classical logic. I argue that this principle should be rejected. Its failure, on my view, does not require failures of logical omniscience on the part of the agent, but results from a view of the update as _mighty_: as encoding what the agent learns might be the case, as well as what must be. (...) The view is motivated by consideration of a puzzle case, obtained by transposing into the context of belief revision a kind of scenario that Kit Fine has used to argue against intensionalism about counterfactuals. Employing the framework of truthmaker semantics, I go on to develop a novel account of belief revision, based on a conception of the update as mighty, which validates natural hyperintensional counterparts of the usual AGM postulates. (shrink)

Loss of self is widely regarded to be a consequence of dementia, and this perceived loss presents a variety of problems - not least because a clear understanding of the concept of self is elusive. This paper suggests a way to cut through problems that arise because we rely on conceptions of self in our understanding of the effects of dementia. It is proposed that we can avoid reliance on the concept of self through an approach based in in bio-phenomenology. (...) Such an approach would help us better understand the inner life of those with dementia and assist us to recognize that even in late stage dementia they are semiotic subjects with unique value. (shrink)

BackgroundNarrative reviews are the commonest type of articles in the medical literature. However, unlike systematic reviews and randomized controlled trials (RCT) articles, for which formal instruments exist to evaluate quality, there is currently no instrument available to assess the quality of narrative reviews. In response to this gap, we developed SANRA, the Scale for the Assessment of Narrative Review Articles.MethodsA team of three experienced journal editors modified or deleted items in an earlier SANRA version based on face validity, item-total correlations, (...) and reliability scores from previous tests. We deleted an item which addressed a manuscript’s writing and accessibility due to poor inter-rater reliability. The six items which form the revised scale are rated from 0 (low standard) to 2 (high standard) and cover the following topics: explanation of (1) the importance and (2) the aims of the review, (3) literature search and (4) referencing and presentation of (5) evidence level and (6) relevant endpoint data. For all items, we developed anchor definitions and examples to guide users in filling out the form. The revised scale was tested by the same editors (blinded to each other’s ratings) in a group of 30 consecutive non-systematic review manuscripts submitted to a general medical journal.ResultsRaters confirmed that completing the scale is feasible in everyday editorial work. The mean sum score across all 30 manuscripts was 6.0 out of 12 possible points (SD 2.6, range 1–12). Corrected item-total correlations ranged from 0.33 (item 3) to 0.58 (item 6), and Cronbach’s alpha was 0.68 (internal consistency). The intra-class correlation coefficient (average measure) was 0.77 [95% CI 0.57, 0.88] (inter-rater reliability). Raters often disagreed on items 1 and 4.ConclusionsSANRA’s feasibility, inter-rater reliability, homogeneity of items, and internal consistency are sufficient for a scale of six items. Further field testing, particularly of validity, is desirable. We recommend rater training based on the “explanations and instructions” document provided with SANRA. In editorial decision-making, SANRA may complement journal-specific evaluation of manuscripts—pertaining to, e.g., audience, originality or difficulty—and may contribute to improving the standard of non-systematic reviews. (shrink)

On one important notion of irrelevance, evidence that is irrelevant in an inquiry may rationally be discarded, and attempts to obtain evidence amount to a waste of resources if they are directed at irrelevant evidence. The familiar Bayesian criterion of irrelevance, whatever its merits, is not adequate with respect to this notion. I show that a modification of the criterion due to Ken Gemes, though a significant improvement, still has highly implausible consequences. To make progress, I argue, we need to (...) adopt a hyperintensional conception of content. I go on to formulate a better, hyperintensional criterion of irrelevance, drawing heavily on the framework of the truthmaker conception of propositions as recently developed by Kit Fine. (shrink)

Philosophy and Phenomenological Research, EarlyView.

Alongside science and law, argumentation is also of central importance in everyday life. But what characterizes a good argument? This question has occupied philosophers and psychologists for centuries. The theory of Bayesian argumentation is particularly suitable for clarifying it, because it allows us to take into account in a natural way the role of uncertainty, which is central to much argumentation. Moreover, it offers the possibility of measuring the strength of an argument in probabilistic terms. One way to do this, (...) implicit in much work, is to identify the strength of an argument with the degree to which the premises of the argument confirm the conclusion. We criticize this prima facie plausible proposal and suggest instead that the strength of an argument has something to do with how much the premises and the conclusion of the argument cohere with each other. This leads to a new probabilistic measure whose properties we examine in more detail. (shrink)