While the epistemic significance of disagreement has been a popular topic in epistemology for at least a decade, little attention has been paid to logical disagreement. This monograph is meant as a remedy. The text starts with an extensive literature review of the epistemology of (peer) disagreement and sets the stage for an epistemological study of logical disagreement. The guiding thread for the rest of the work is then three distinct readings of the ambiguous term ‘logical disagreement’. Chapters 1 and (...) 2 focus on the Ad Hoc Reading according to which logical disagreements occur when two subjects take incompatible doxastic attitudes toward a specific proposition in or about logic. Chapter 2 presents a new counterexample to the widely discussed Uniqueness Thesis. Chapters 3 and 4 focus on the Theory Choice Reading of ‘logical disagreement’. According to this interpretation, logical disagreements occur at the level of entire logical theories rather than individual entailment-claims. Chapter 4 concerns a key question from the philosophy of logic, viz., how we have epistemic justification for claims about logical consequence. In Chapters 5 and 6 we turn to the Akrasia Reading. On this reading, logical disagreements occur when there is a mismatch between the deductive strength of one’s background logic and the logical theory one prefers (officially). Chapter 6 introduces logical akrasia by analogy to epistemic akrasia and presents a novel dilemma. Chapter 7 revisits the epistemology of peer disagreement and argues that the epistemic significance of central principles from the literature are at best deflated in the context of logical disagreement. The chapter also develops a simple formal model of deep disagreement in Default Logic, relating this to our general discussion of logical disagreement. The monograph ends in an epilogue with some reflections on the potential epistemic significance of convergence in logical theorizing. (shrink)

This paper explores the application of hinge epistemology to deep disagreement. Hinge epistemology holds that there is a class of commitments—hinge commitments—which play a fundamental role in the structure of belief and rational evaluation: they are the most basic general ‘presuppositions’ of our world views which make it possible for us to evaluate certain beliefs or doubts as rational. Deep disagreements seem to crucially involve disagreements over such fundamental commitments. In this paper, I consider pessimism about deep disagreement, the thesis (...) that such disagreements are rationally irresolvable, and ask whether the Wittgensteinian account of deep disagreement—according to which such disagreements are disagreements over hinge commitments—provides adequate support for pessimism. I argue that the answer to this question depends on what hinge commitments are and what our epistemic relation to them is supposed to be. I argue for two core claims. First, that non-epistemic theories of hinge commitments provide adequate support for pessimism. Nevertheless, such theories have highly implausible consequences in the context of deep disagreement. Secondly, at least one epistemic theory of hinge commitments, the entitlement theory, permits optimism about such disagreements. As such, while hinge epistemology is mainly pessimistic about deep disagreement, it doesn’t have to be. (shrink)

What is the nature of deep disagreement? In this paper, I consider two similar albeit seemingly rival answers to this question: the Wittgensteinian theory, according to which deep disagreements are disagreements over hinge propositions, and the fundamental epistemic principle theory, according to which deep disagreements are disagreements over fundamental epistemic principles. I assess these theories against a set of desiderata for a satisfactory theory of deep disagreement, and argue that while the fundamental epistemic principle theory does better than the Wittgensteinian (...) theory on this score, the fundamental epistemic principle theory nevertheless struggles to explain the variety of deep disagreement. (shrink)

This paper explores the application of hinge epistemology to deep disagreement. Hinge epistemology holds that there is a class of commitments—hinge commitments—which play a fundamental role in the structure of belief and rational evaluation: they are the most basic general ‘presuppositions’ of our world views which make it possible for us to evaluate certain beliefs or doubts as rational. Deep disagreements seem to crucially involve disagreements over such fundamental commitments. In this paper, I consider pessimism about deep disagreement, the thesis (...) that such disagreements are rationally irresolvable, and ask whether the Wittgensteinian account of deep disagreement—according to which such disagreements are disagreements over hinge commitments—provides adequate support for pessimism. I argue that the answer to this question depends on what hinge commitments are and what our epistemic relation to them is supposed to be. I argue for two core claims. First, that non-epistemic theories of hinge commitments provide adequate support for pessimism. Nevertheless, such theories have highly implausible consequences in the context of deep disagreement. Secondly, at least one epistemic theory of hinge commitments, the entitlement theory, permits optimism about such disagreements. As such, while hinge epistemology is mainly pessimistic about deep disagreement, it doesn’t have to be. (shrink)

Should scientific facts and methods have an epistemically privileged status in public reason? In Rawls’s public reason account he asserts what we will label the Scientific Standard Stricture: citizens engaged in public reason must be guided by non-controversial scientific methods, and public reason must be in line with non-controversial scientific conclusions. The Scientific Standard Stricture is meant to fulfill important tasks such as enabling the determinateness and publicity of the public reason framework. However, Rawls leaves us without elucidation with regard (...) to when science is and is not ‘non-controversial’ and more importantly, we are left without a justification for a stricture which excludes certain controversial beliefs and methods of inquiry from the realm of political justification. In this article, we offer what we deem to be the most plausible interpretation of Rawls’s Scientific Standards Stricture. We then use Rawls’s general theoretical framework to examine various potential justifications for privileging these ‘non-controversial’ scientific methods and conclusions. We conclude that no viable justification is available to Rawls. (shrink)

The relationship between the necessity to ensure that information is shared in the stages of deliberation and the overcoming of what Dryzek (2001) called constriction of deliberative economy is directly related to the proponents and opponents’ propensity to submit and add information differently, in a plural manner. This article describes the salient features of the deliberative turn in order to defend that this propensity is not individual. The evolution of the public space in science and in politics are both paradigmatic (...) examples to appreciate that individual deliberation, and even mere aggregation of opinions, are consistently interpreted only if they are part of social practices and collective institutions aimed at defending tolerance towards positions, beliefs and interpretations that are different or even confronted. This paper argues that the so called model of contestatory deliberative democracy contributes to the acquisition of knowledge precisely because it fosters a plurality of epistemic states associated with practices as consensus and dissent. (shrink)

We all agree that democratic decision-making requires a factual input, and most of us assume that when the pertinent facts are not in plain view they should be furnished by well-functioning scientific institutions. But how should liberal democracy respond when apparently sincere, rational and well-informed citizens object to coercive legislation because it is based on what they consider a misguided trust in certain parts of science? Cases are familiar, the most prominent concerning climate science and evolution, but one may also (...) count GMO-skepticism and vaccine-skepticism, and there are plenty of others. The paper defends what I, borrowing an expression from Badiola, call Science as Public Reason, asserting roughly that some policy-relevant factual proposition P is part of public reason if and only if there is consensus about P among scientific experts in the relevant well-functioning scientific institutions. I defend this view against the controversiality objection claiming that scientific findings cannot in this general way pass as public reason as they are sometimes controversial among reasonable citizens. My preferred line of defense is what I call Dogmatism about Science as Public Reason, which roughly amounts to insisting on Science as Public Reason on the ground that it is a philosophically well-motivated view, while conceding that it may not be acceptable to all minimally rational and well-informed individuals. (shrink)

ABSTRACTIn his account of public reason Rawls assumes that some facts ought to be treated as ‘fixed’, or beyond reasonable disagreement. These include, for him, facts upon which there is a scientif...

Suppose we have a persistent disagreement about a particular set of policy options, not because of an underlying moral disagreement, or a mere conflict of interest, but rather because we disagree about a crucial non-normative factual assumption underlying the justification of the policy choices. The main question in the paper is what political legitimacy requires in such cases, or indeed whether there are defensible answers to that question. The problem of political legitimacy in fact-dependent policy disagreements has received almost no (...) attention in political philosophy, which has focused mostly on value disagreements and proposed theories of legitimate coercive legislation in valuedependent disagreements. The paper presents an argument showing that under certain plausible assumptions regarding legitimacy, there are serious difficulties in identifying legitimate choices in fact-dependent policy disagreements. This may be unsurprising to political philosophers preoccupied with value-based disagreements, perhaps because it has been assumed that legitimacy-related concerns are irrelevant to fact-dependent policy disagreements. The paper argues that this response is premature. If we should care about legitimacy et al.l, then it is by no means clear why we should ignore issues of legitimacy in policy-disputes that depend on factual disagreements. The paper ends by defining a set of possibilities that merit further exploration in search of a theory of legitimacy in fact-dependent policy disagreements. (shrink)