Checking is a very common concept for describing a subject's epistemic goals and actions. Surprisingly, there has been no philosophical attention paid to the notion of checking. This is the fi rst book to develop a comprehensive epistemic theory of checking. The author argues that sensitivity is necessary for checking but not for knowing, thereby fi nding a new home for the much discussed modal sensitivity principle. He then uses the distinction between checking and knowing to explain central puzzles about knowledge, particularly those concerning knowledge closure, bootstrapping, and the skeptical puzzle. Knowing and Checking: An Epistemological Investigation will be of interest to epistemologists and other philosophers looking for a general theory of checking and testing or for new solutions to central epistemological problems. Guido Melchior is Privatdozent and project leader at the University of Graz and recurring visiting scholar at the University of Arizona. He has previously published in Philosophical Studies , Erkenntnis , and Episteme, among other journals. Knowing and Checking First published 2019 by Routledge 52 Vanderbilt Avenue, New York, NY 10017 and by Routledge 2 Park Square, Milton Park, Abingdon, Oxon OX14 4RN Routledge is an imprint of the Taylor & Francis Group, an informa business © 2019 Taylor & Francis The right of Guido Melchior to be identifi ed as author of this work has been asserted by him/ in accordance with sections 77 and 78 of the Copyright, Designs and Patents Act 1988. All rights reserved. No part of this book may be reprinted or reproduced or utilised in any form or by any electronic, mechanical, or other means, now known or hereafter invented, including photocopying and recording, or in any information storage or retrieval system, without permission in writing from the publishers. Trademark notice : Product or corporate names may be trademarks or registered trademarks, and are used only for identifi cation and explanation without intent to infringe. Library of Congress Cataloging-in-Publication Data Names: Melchior, Guido, author. Title: Knowing and checking : an epistemological investigation / Guido Melchior. Description: 1 [edition]. | New York : Taylor & Francis, 2019. | Series: Routledge studies in epistemology ; 3 | Includes bibliographical references and index. Identifi ers: LCCN 2019006701 | ISBN 9780367141127 (hardback) Subjects: LCSH: Knowledge, Theory of. Classifi cation: LCC BD161 .M398 2019 | DDC 121-dc23 LC record available at https://lccn.loc.gov/2019006701 Wi ISBN: 978-0-367-14112-7 (hbk) ISBN: 978-0-429-03023-9 (ebk) Typeset in Sabon by Apex CoVantage, LLC Contents Acknowledgments vii PART I Checking 1 1 Introduction: The Methodological Approach 3 2 Modal Knowledge Accounts 9 2.1 Nozick's Modal Knowledge Account 9 2.2 Problems for Nozick's Modal Knowledge Account 15 2.3 Sensitivity Accounts: The Second Wave 20 2.4 Safety 22 3 SAC: A Sensitivity Account of Checking 29 3.1 Checking and Other Epistemic Actions 29 3.2 Modality: From Beliefs to Methods 37 3.3 Perfect Checking Methods 45 3.4 Checking and Sensitivity 48 3.5 Checking and Safety 55 3.6 Asymmetric Methods, Adherence, and Negative Safety 58 3.7 Checking and Knowing 66 3.8 Resolving the Generality Problem 73 3.9 Resolving Kripke's Closure Problem 76 4 Checking, Alternatives, and Discrimination 89 4.1 Checking and Alternatives 89 4.2 Checking and Discriminating 103 5 Checking, Inferences, and Necessities 111 5.1 Nozick on Inferential Knowledge 111 5.2 Checking and Inferences 118 5.3 Checking and Necessary Truths 125 vi Contents PART II Checking and Knowledge Puzzles 139 6 SAC and Knowledge Puzzles 141 6.1 SAC and Knowledge Puzzles: The Core Connection 141 6.2 Low-Stakes/High-Stakes Puzzles 149 6.3 Closure Puzzles 159 6.3.1 KSAC-Explanations of Closure Puzzles 164 6.3.2 KSAC-Solutions to Closure Puzzles 170 6.3.3 KSAC-Explanations of Closure Puzzles and Alternative Explanations 179 7 Checking and Bootstrapping 193 7.1 Bootstrapping and Checking 193 7.2 Bootstrapping and Knowing 203 7.2.1 Explaining the Bootstrapping Puzzle 203 7.2.2 Solutions to the Bootstrapping Puzzle 208 8 SAC and the Skeptical Puzzle 214 8.1 The Skeptical Puzzle and the Moorean Puzzle 214 8.2 Explaining the Skeptical Puzzle 220 8.2.1 Doubting and Checking One's Own Beliefs 220 8.2.2 Varieties and Limits of Checking Beliefs 223 8.2.3 Explaining and Solving the Moorean Puzzle 231 8.3 The Heterogeneity Problem 241 8.3.1 The Heterogeneity Problem for Higher-Level Beliefs 241 8.3.2 The Heterogeneity Problem for Moorean Reasoning 245 8.3.3 The Heterogeneity Problem for Existing Sensitivity Accounts of Knowledge 249 8.3.4 Resolving the Heterogeneity Problem 254 8.3.5 Resolving a Generality Problem for Moorean Reasoning 256 Appendix 264 References 268 Index 277 Knowing and Checking: An Epistemological Investigation Guido Melchior Chapter 1, Introduction This introductory Chapter provides an overview of "Knowing and Checking: An Epistemological Investigation" and its methodological approach. In Part I of the book, I develop a sensitivity account of checking. In Part II, I use this theory for explaining central puzzles about knowledge, for example the skeptical puzzle. Against orthodox epistemology, and especially against knowledge-first epistemology, my methodological approach is to provide an analysis of common but philosophically neglected epistemic concepts such as checking and to use this analysis to explain puzzles about knowledge. ________________________________________________________________ Chapter 2, Modal Knowledge Accounts This Chapter provides an overview of modal knowledge accounts. In section 2.1, it present Nozick's sensitivity based knowledge account and, in section 2.2, three well known problems for this account: insensitive inductive knowledge, implausible closure failure, and the problem of one-sided methods. In section 2.3, it discusses alternative sensitivity accounts as proposed by DeRose, Black, Roush and Becker that attempt to handle problems of insensitive knowledge and/or closure failure better than Nozick's account does. Section 2.4 is devoted to the alternative modal principle of safety and problems for safety accounts of knowledge. ________________________________________________________________ Chapter 3, SAC: A Sensitivity Account of Checking This Chapter develops a sensitivity account of checking. It begins by sketching two necessary conditions on checking, first that S uses the method with the intention of determining whether p is true and second that M is an appropriate method with respect to p. In section 3.1, it discusses the first condition, which specifies the intentional features of the checking subject. Furthermore, it introduces some terminology and distinguishes between ex ante reports about checking and ex post reports along with defining the technical notion of checking that p is true. Section 3.1 ends by providing a natural language analysis concerning 'checking' and related concepts such as 'determining,' 'checking out,' 'double-checking,' 'testing,' and 'settling a question.' In the following sections, 3.2-3.9, this chapter discusses the second condition on checking, which concerns the modal features of the method used. It defines any method that is appropriate with respect to p as a checking method for p. First, it provides a detailed account of modal features of methods instead of modal features of beliefs. Second, it sketches the features of ideal methods for checking whether p. Third, it argues that sensitivity is necessary for checking and, fourth, it explains why safety is not sufficient. Fifth, it contends that a sensitivity based checking account does not suffer from Luper-Foy's problem of one-sided methods. Sixth, it elaborates necessary and sufficient conditions for checking methods that are asymmetric with respect to p and p. Seventh, it analyzes the relations between the provided account of checking and existing knowledge accounts. Finally, it is argued that the proposed checking account does not suffer from the generality problem and that Kripke's barn façade example does not pose a counter-example. Chapter 4, Checking, Alternatives, and Discrimination The first part of Chapter 4, extends the account of checking, developed in Chapter 3. First, Chapter 4 provides a more fine-grained analysis of checking by distinguishing between cases like checking that it is true that Peter cleaned, checking that Peter (and not somebody else) cleaned the kitchen or checking that Peter cleaned the kitchen (and not something else). Second, it investigates checking with regard to particular alternatives, e.g. checking that Peter and not Frank cleaned the kitchen. Third, it analyzes checking plus wh-clauses, e.g. checking who cleaned the kitchen. In the second part of Chapter 4, it is shown how we can elaborate a theory of discriminating in analogy to the modal theory of checking viz. a theory about the conditions for having the capacity to discriminate Fs from Gs. The reader will see that sensitivity is not only necessary for checking but also for discriminating, i.e. S cannot discriminate Fs from Gs via M if, in the nearest possible worlds where x is G, M indicates that x is F. ________________________________________________________________ Chapter 5, Checking, Inferences, and Necessities Observation and the uses of technical devices are paradigmatic methods for checking. In these cases, the method often directly indicates that the target proposition is true (or indicates that it is false). However, in many cases we want to check a proposition whose truth or falsity observation or technical devices cannot indicate directly. In these cases, inferences may be involved in the checking processes. This chapter investigates which kinds of inferences can be involved in checking methods. In the first section, it presents Nozick's sensitivity based account of inferential knowledge and its consequences for deduction, induction and abduction. The reader will see that some instances of deduction can yield knowledge but some others cannot. This is in line with Nozick's take on knowledge closure. Moreover, some instances of induction cannot yield knowledge, as critics of Nozick point out, though some others can, a rather neglected fact. Abduction can yield inferential knowledge, on Nozick's account, if the inference is one to the best explanation. Here Nozick's account of inferential knowledge fits well with our intuitive understanding of proper abductive inferences. In the second section, it is shown that we get the same results for checking and it is argued that this does not pose a problem for SAC. The last section investigates checking of necessary truths. Orthodox semantics of counterfactual conditionals has it that any method trivially fulfills the sensitivity and safety condition for necessary truths. Thus, one should be able to check necessary truths by using any method, which is highly implausible. It is argued that non-orthodox semantics for counterfactuals that also takes into account impossible worlds avoids this problem and provides a natural extension of SAC to necessary truths. ________________________________________________________________ Chapter 6, SAC and Knowledge Puzzles Part I of 'Knowing and Checking' presents SAC, a sensitivity account of checking. Part II investigates how SAC can contribute to explaining and solving existing philosophical puzzles about knowledge. This part will not defend a particular account of knowledge. Consequently, it cannot and will not explicate the actual connections between checking and knowing. Nevertheless, SAC can be used for explaining existing puzzles about knowledge. This can be done by revealing the connections between checking and our intuitions about knowing, thereby leaving open whether our knowledge intuitions are actually right or wrong. Chapter 6 first develops the core connection between checking and intuitions about knowing. Second, it presents low-stakes/high-stakes puzzles and closure puzzles, along with existing solutions to these puzzles. Third, it discusses how SAC can explain low-stakes/high-stakes puzzles and contribute to existing solutions. Fourth, it undertakes this investigation for closure puzzles and compares the SAC-based explanation of closure puzzles to alternatives. It will be shown that our intuitions about checking and knowing can only explain some lowstakes/high-stakes puzzles, but they provide the best explanation for closure puzzles. Various existing solutions to closure puzzles, such as strict and moderate invariantism and contextualism, are compatible with the SAC-based explanation. ________________________________________________________________ Chapter 7, Checking and Bootstrapping The first section of Chapter 7 contains a theory about checking and bootstrapping. The second section investigates how this theory can be used to explain and to solve knowledge puzzles about bootstrapping. It is first shown that inductive bootstrapping is a monotonous method that always indicates that the source in question is reliable regardless of whether it actually is reliable or not. For this reason, bootstrapping fails to be a method of checking a source's reliability. This is also true for deductive bootstrapping and bootstrapping about the accuracy of a source's indications. Some alternative ways of checking the reliability or accuracy of a source are investigated and it is concluded that these possibilities have certain limitations. Second, it is argued that we have to distinguish between checking that p, checking that a source O truly indicates that p and checking of O's indication that p that it is true. This distinction will also be relevant in Chapter 8 when various ways of checking whether one's own beliefs are true are investigated. We will see that each of these checking processes has different sensitivity conditions and, consequently, different limitations. The second section of Chapter 7 investigates how SAC and KSAC can explain knowledge puzzles about bootstrapping and how they can contribute to solving them. ________________________________________________________________ Chapter 8, SAC and the Skeptical Puzzle This final chapter provides an explanation of the skeptical puzzle and the Moorean puzzle that is based on a sensitivity account of checking, SAC. Section 8.1 surveys the contemporary debate about skepticism and Mooreanism. Section 8.2 presents a SAC-based explanation of the skeptical puzzle and the Moorean puzzle. It begins by discussing doubting and its relationship to checking one's own beliefs, contrasting them with ordinary self-reflection. It argues that Moorean reasoning is a way of acquiring higher-level knowledge and knowledge that the skeptical hypotheses are false. However, it is not a way of checking of one's beliefs in the denials of the skeptical hypotheses that they are true. This explanation of the Moorean puzzle fits well with moderate invariantism and with a SAC-based version of contextualism. Section 8.3 discusses a heterogeneity problem concerning bootstrapping and Mooreanism that existing sensitivity accounts of knowledge are faced with along with a generality problem about higher-level knowledge. It is shown that a SAC-based solution suffers neither from the heterogeneity problem nor from the generality problem.