The Routledge Handbook of Metaphysical Grounding 9781351258838, 1351258834

Table of contents :
Cover
Half Title
Series
Title
Copyright
Dedication
Contents
Notes on Contributors
Acknowledgments
Introduction
Part I History
Introduction
1 Ancient
2 Aristotelian Demonstration
3 Medieval and Early Modern
4 Principle of Sufficient Reason
5 Bolzano
6 Austro-German Phenomenologists
Part II Explanation and Determination
Introduction
7 Dependence
8 Explanation
9 Meta-Ground
10 Necessity
11 Skeptical Doubts
12 Anti-Skeptical Rejoinders
13 Varieties
Part III Logic and Structure
Introduction
14 Logics
15 Granularity
16 Infinite Descent
17 Strict Partial Order
18 Puzzles
Part IV Connections
Introduction
19 Analyticity
20 Cause
21 Emergence
22 Essence
23 Fundamentality
24 Modality
25 Ontology
26 Realism
27 Structure
28 Truthmaking
Part V Applications
Introduction
29 Identity
30 Laws of Metaphysics
31 Laws of Nature
32 Logic
33 Mind
34 Normativity
35 Physicalism
36 Semantics
37 Social Entities
The Essential Glossary of Ground
Index

Citation preview

“Grounding is one of the central topics in contemporary metaphysics.This collection represents the cutting edge of work in this fast-developing area, and is a must have both for veterans of debates about grounding and philosophers wanting to explore how thinking about grounding interacts with their favourite philosophical problems.” —Daniel Nolan, University of Notre Dame

THE ROUTLEDGE HANDBOOK OF

METAPHYSICAL GROUNDING

Some of philosophy’s biggest questions, both historically and today, are in-virtue-of questions: In virtue of what is an action right or wrong? In virtue of what am I the same person my mother bore? In virtue of what is an artwork beautiful? Philosophers attempt to answer many of these types of in-virtue-of questions, but philosophers are also increasingly focusing on what an in-virtue-of question is in the first place. Many assume, at least as a working hypothesis, that in-virtue-of questions involve a distinctively metaphysical kind of determinative explanation called “ground.” This Handbook surveys the state of the art on ground as well as its connections and applications to other topics. The central issues of ground are discussed in 37 chapters, all written exclusively for this volume by a wide range of leading experts.The chapters are organized into the following sections: I. II. III. IV. V.

History Explanation and Determination Logic and Structure Connections Applications

Introductions at the start of each section provide an overview of the section’s contents, and a list of Related Topics at the end of each chapter points readers to other germane areas throughout the volume. The resulting volume is accessible enough for advanced students and informative enough for researchers. It is essential reading for anyone hoping to get clearer on what the biggest questions of philosophy are really asking. Michael J. Raven is Associate Professor of philosophy at the University of Victoria and Affiliate Associate Professor of philosophy at the University of Washington, Co-Chief Editor of Metaphysics, and a founding member of the Canadian Metaphysics Collaborative. His research focuses on metaphysics, philosophy of language and mind, and epistemology.

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Also available: THE ROUTLEDGE HANDBOOK OF PHILOSOPHY OF THE CITY Edited by Sharon M. Meagher, Samantha Noll, and Joseph S. Biehl THE ROUTLEDGE HANDBOOK OF PANPSYCHISM Edited by William Seager THE ROUTLEDGE HANDBOOK OF PHILOSOPHY OF RELATIVISM Edited by Martin Kusch THE ROUTLEDGE HANDBOOK OF PHILOSOPHY OF COLOUR Edited by Derek H. Brown and Fiona Macpherson THE ROUTLEDGE HANDBOOK OF METAPHYSICAL GROUNDING Edited by Michael J. Raven THE ROUTLEDGE HANDBOOK OF COLLECTIVE RESPONSIBILITY Edited by Saba Bazargan-Forward and Deborah Tollefsen For more information about this series, please visit: www.routledge.com/Routledge-Handbooksin-Philosophy/book-series/RHP

THE ROUTLEDGE HANDBOOK

OF METAPHYSICAL

GROUNDING

Edited by Michael J. Raven

First published 2020

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 © 2020 Taylor & Francis The right of Michael J. Raven to be identified as the author of the editorial material, and of the authors for their individual chapters, has been asserted 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 identification and explanation without intent to infringe. Library of Congress Cataloging-in-Publication Data A catalog record for this book has been requested

ISBN: 978-0-8153-6649-2 (hbk)

ISBN: 978-1-351-25884-5 (ebk)

Typeset in Bembo

by Apex CoVantage, LLC

Justin Zylstra (1987–2019), author of the chapter “Essence”, died shortly after

this volume was delivered to the publisher. Justin was a promising and prolific young

philosopher with a bright future. Many of the other authors had the good fortune

to know him and his work.The imprint left by Justin’s insights and his thoughtful,

gently tenacious commitment to philosophy will continue influencing us, even

while his presence is sorely missed.This volume is dedicated with admiration

and affection to Justin.

CONTENTS

Notes on Contributors Acknowledgments

xiii xvii

Introduction Michael J. Raven

1

PART I

History

15

Introduction Michael J. Raven

17

1 Ancient Phil Corkum

20

2 Aristotelian Demonstration Marko Malink

33

3 Medieval and Early Modern Margaret Cameron

49

4 Principle of Sufficient Reason Fatema Amijee

63

5 Bolzano Stefan Roski

76

ix

Contents

6 Austro-German Phenomenologists Kevin Mulligan

90

PART II

Explanation and Determination

103

Introduction Michael J. Raven

105

7 Dependence Benjamin Schnieder

107

8 Explanation Martin Glazier

121

9 Meta-Ground Jon Erling Litland

133

10 Necessity Alexander Skiles

148

11 Skeptical Doubts Kathrin Koslicki

164

12 Anti-Skeptical Rejoinders Louis deRosset

180

13 Varieties Kevin Richardson

194

PART III

Logic and Structure

209

Introduction Michael J. Raven

211

14 Logics Francesca Poggiolesi

213

15 Granularity Fabrice Correia

228

x

Contents

16 Infinite Descent T. Scott Dixon

244

17 Strict Partial Order Naomi Thompson

259

18 Puzzles Stephan Krämer

271

PART IV

Connections

283

Introduction Michael J. Raven

285

19 Analyticity Tom Donaldson

288

20 Cause Jennifer Wang

300

21 Emergence Stephan Leuenberger

312

22 Essence Justin Zylstra

324

23 Fundamentality Ricki Bliss

336

24 Modality David Mark Kovacs

348

25 Ontology Noël B. Saenz

361

26 Realism Olla Solomyak

375

27 Structure Tuomas E.Tahko

387

xi

Contents

396

28 Truthmaking Kelly Trogdon PART V

Applications

409

Introduction Michael J. Raven

411

29 Identity Erica Shumener

413

30 Laws of Metaphysics Tobias Wilsch

425

31 Laws of Nature Nina Emery

437

32 Logic Michaela M. McSweeney

449

33 Mind Alyssa Ney

460

34 Normativity Stephanie Leary

472

35 Physicalism Amanda Bryant

484

36 Semantics Kit Fine

501

37 Social Entities Asya Passinsky

510

The Essential Glossary of Ground Index

521 523

xii

NOTES ON CONTRIBUTORS

Fatema Amijee is Assistant Professor in the Department of Philosophy at the National Uni­ versity of Singapore. Ricki Bliss is an Assistant Professor of philosophy at Lehigh University. Prior to this, she was an Alexander von Humboldt Research Fellow at the University of Hamburg, Germany, and a Japan Society for the Promotion of Sciences Research Fellow at Kyoto University, Japan. Amanda Bryant is a postdoctoral research fellow, working on the FCT-funded project Emer­ gence in the Natural Sciences (EITNS), based at the Centre of Philosophy at the University of Lisbon. Her work primarily concerns naturalism and its application to metaphysics. Margaret Cameron is Professor of philosophy and Head of the School of Historical and Philosophical Studies at the University of Melbourne. She has published in the areas of medieval and early modern philosophy as well as the history of the philosophy of language and mind. Phil Corkum is Associate Professor of philosophy at the University of Alberta. He works in both ancient philosophy and contemporary metaphysics, and has published in Phronesis, the Brit­ ish Journal for the History of Philosophy, and Synthese, among other journals. Fabrice Correia is Professor of analytic philosophy at the University of Geneva, Switzerland. He is the author of Existential Dependence and Cognate Notions (2005) and a co-author (with Benjamin Schnieder) of Grounding: Understanding the Structure of Reality (2012). Louis deRosset is Professor of philosophy at the University of Vermont. Scott Dixon is Assistant Professor of philosophy at Ashoka University near New Delhi, India, and a Kit Fine Fellow at Universität Hamburg. Tom Donaldson is Assistant Professor in the Philosophy Department at Simon Fraser Uni­ versity, Canada.With Stephen Stich, he wrote the textbook Philosophy:Asking Questions, Seeking Answers (2018). He is working on a book on analyticity and arithmetic. xiii

Notes on Contributors

Nina Emery is Assistant Professor of philosophy at Mount Holyoke College. Her research takes up questions at the intersection of metaphysics and philosophy of physics. Her recent publica­ tions include “Laws and their Instances” in Philosophical Studies. Kit Fine is University Professor and Silver Professor of Philosophy and Mathematics at New York University. He is the author of Reasoning with Arbitrary Objects (1985), The Limits of Abstrac­ tion (2002), Modality and Tense (2005), and Semantic Relationism (2007). Martin Glazier is Research Assistant in philosophy at the University of Hamburg. He is the author of several papers in metaphysics. Kathrin Koslicki is Professor and Tier 1 Canada Research Chair in Epistemology and Meta­ physics in the Department of Philosophy at the University of Alberta, Canada. Her research interests in philosophy lie mainly in metaphysics, the philosophy of language, and ancient Greek philosophy, especially Aristotle. In her two books (The Structure of Objects, 2008; and Form, Mat­ ter, Substance, 2018), she defends a neo-Aristotelian hylomorphic analysis of concrete particular objects as compounds of matter (hūlē) and form (morphē or eidos). David Mark Kovacs is Lecturer in philosophy at Tel Aviv University, Israel. Stephan Krämer is Lecturer in Philosophy at the University of Hamburg, Germany. He is the author of On What There Is For Things to Be (2014) and has published several articles on grounding. Stephanie Leary is Assistant Professor in the Department of Philosophy at McGill University, Montreal, Quebec, Canada. Stephan Leuenberger is Senior Lecturer in philosophy at the University of Glasgow. His pub­ lications on issues in interlevel metaphysics include “Grounding and Necessity” (Inquiry, 2014), “From Grounding to Supervenience?” (Erkenntnis, 2014), and “Global Supervenience without Reducibility” (Journal of Philosophy, 2018). Jon Erling Litland is Assistant Professor of philosophy at the University of Texas at Austin. He has written numerous articles about ground and its logic and is working on a book manuscript about ground and paradox. Marko Malink is Professor of philosophy and classics at New York University. He is the author of Aristotle’s Modal Syllogistic (2013). He has published articles on the logic and metaphysics of Aristotle and Leibniz. Some of his articles have been included in the Philosopher’s Annual (2013, 2016, 2018). Michaela M. McSweeney is Assistant Professor of philosophy at Boston University, Boston, Massachusetts. Kevin Mulligan is Professor of philosophy, University of Italian Switzerland, Director of Research, Institute of Philosophical Studies, Lugano, and Honorary Professor of Analytic Phi­ losophy, University of Geneva. He is a member of the Royal Swedish Academy of Letters and the Academia Europaea. xiv

Notes on Contributors

Alyssa Ney is Professor of philosophy at the University of California, Davis. She is the author of Metaphysics: An Introduction (2014) and The World in the Wave Function (forthcoming). She works in metaphysics, philosophy of physics, and the philosophy of mind. Asya Passinsky is Lecturer in philosophy at Dartmouth College in Hanover, New Hampshire. She works on topics including the metaphysics of social objects, grounding in the social realm, and feminist metaphysics. She is the author of “Social Objects, Response-Dependence, and Realism” and “Finean Feminist Metaphysics.” Francesca Poggiolesi is Senior Researcher at IHPST-CNRS, Paris, France. Her last mono­ graph is Gentzen Calculi for Modal Propositional Logic, 2010; she is also the author of many articles published in international reviews. Michael J. Raven is Associate Professor of philosophy at the University of Victoria and Affili­ ate Associate Professor of philosophy at the University of Washington, Co-Chief Editor of Meta­ physics, and a founding member of the Canadian Metaphysics Collaborative. His research focuses on metaphysics, philosophy of language and mind, and epistemology. Kevin Richardson is Assistant Professor of philosophy at North Carolina State University. He works on metaphysics and philosophy of language. Stefan Roski is Research Associate at the University of Hamburg. He is the author of Bolzano’s Conception of Grounding and has published on grounding, Bolzano, and explanation. Noël B. Saenz is Assistant Professor in the Philosophy Department at the University of Illinois Urbana-Champaign. Benjamin Schnieder is Professor for Theoretical Philosophy at the Department of Philoso­ phy, University of Hamburg, Germany. Together with Fabrice Correia, he edited Metaphysical Grounding, and he authored several papers on grounding. Erica Shumener is Assistant Professor in the Philosophy Department at the University of Pittsburgh in the United States. Alexander Skiles is Assistant Teaching Professor at Rutgers University. His research mostly focuses on three topics: (i) noncausal explanation in metaphysics and the sciences, (ii) the meta­ physics, epistemology, and logic of identity, essence, and individuation, and (iii) the nature of existence. He is also interested in various logic and metaphysical issues that arise in classical Hindu and Buddhist thought. Olla Solomyak is Polonsky Postdoctoral Fellow at the Van Leer Jerusalem Institute. She works on the metaphysics of perspectives and on questions surrounding realism, ground, time, modal­ ity, and the first person. Tuomas E. Tahko is Reader in Metaphysics of Science at the University of Bristol, UK. He is the author of An Introduction to Metametaphysics (CUP, 2015) and editor of Contemporary Aristo­ telian Metaphysics (CUP, 2012), and has published numerous articles on metaphysics, philosophy of science, and philosophical logic. xv

Notes on Contributors

Naomi Thompson is Lecturer in philosophy at the University of Southampton in the UK. From 2017 to 2020, she is also a core member of the Metaphysical Explanation research group based at the University of Gothenburg in Sweden. Kelly Trogdon is Associate Professor at Virginia Tech in Blacksburg,VA, USA. Recent publi­ cations include “Prioritizing Platonism” with Sam Cowling (Philosophical Studies 176/8, 2019: 2029–2042) and “Grounding-Mechanical Explanation” (Philosophical Studies 175/6, 2018: 1289–1309). Jennifer Wang is Assistant Professor of philosophy at Simon Fraser University in Canada. She works primarily on metaphysical issues concerning modality. Tobias Wilsch is a junior faculty member in the Department of Philosophy at the University of Tübingen, Germany. Justin Zylstra (1987–2019) was Visiting Research Associate at Trinity College, University of Toronto, and Visiting Faculty in the Institute of Philosophy and Semiotics at the University of Tartu.

xvi

ACKNOWLEDGMENTS

My interest in ground (at least by name) was sparked by Kit Fine’s brilliantly original and enormously influential article “The Question of Realism” during my first academic year as a graduate student at New York University (2003–2004). Kit was on leave that year, and I was busy writing seminar papers on other topics when he returned. But around 2005, my focus on ground intensified. When I started writing my dissertation a year later, ground played a prominent role at the outset.At the time, few were aware of ground as such, and little had been published on it. Even in those lonely times, I often felt excitement that we in the know were on the cusp of something important (and sometimes—when the distinctive pessimism of a gradu­ ate student dug in—that we were on a precipice staring down at the abyss). I could not have imagined back then the torrent of interest in ground that would soon follow.And I certainly did not envision later editing an entire volume on the topic. I am grateful to Daniel Nolan, Routledge, and especially Andrew Beck for the opportunity to do so. My initial plans for the volume benefited greatly from Andrew’s advice as well as the advice from three anonymous referees. My thanks to them all. Since first getting interested in ground, I have learned a great deal from many others also interested in ground, whether as friends or as foes. Although they are too numerous for me to list or recollect fully, I still wish to express my gratitude to them collectively. I was fortunate enough to recruit many of them individually to contribute to this volume. Each of the volume’s contributors deserves my great thanks. Their essays are testaments to their considerable philo­ sophical energy and insight. And the timely publication of this volume is a testament to their diligence. It was a pleasure and a privilege working with them all. The volume not only benefitted from the individual labors of each contributor but also from two joint efforts.The first of these was the Hamburg Workshop on Metaphysical Ground. This workshop united most contributors and helped coordinate the preparation of their essays. Robert Schwartzkopff organized this workshop. Organizing is often an invisible and underap­ preciated task. My sincere thanks to Robert for doing such a terrific job. Funding was provided by Kit Fine’s Anneliese Maier Research Prize from the Alexander von Humboldt Foundation, by a Connection Grant from the Social Sciences and Humanities Research Council of Canada, and by the University of Victoria and its Philosophy Department. I am grateful for their financial support.

xvii

Acknowledgments

The other joint effort also benefitted many of the volume’s essays. Kit Fine taught a master class on this volume at the Università della Svizzera italiana (Lugano). Kit and his students dis­ cussed many of the essays and provided authors and me with detailed comments and advice. On behalf of these authors, I am grateful to Kit and his students for their feedback. Writing the volume’s introduction was a challenge. On the one hand, it was exciting to reflect on the state of the art and to frame the volume’s essays. On the other hand, it was nervewracking trying to accessibly and fairly characterize issues and controversies still in development.The introduction benefitted greatly from encouragement and feedback from Kit Fine, Jon Erling Litland, Colin Marshall, Conor Mayo-Wilson, and Ryan Tonkin. Ryan Tonkin also served as an editorial assistant in the preparation of the manuscript. Many improvements stemmed directly from his diligence, sensible advice, and keen eye for detail. I would like to thank Ryan for his excellent work. I would also like to thank Rose Choi for the beautiful cover art. Her creative mind allowed her to conceive of it merely from my vague rambles about levels, foundations, hierarchies, and structures. I am grateful for the hard work she put into its design and for the much harder work of being my partner. In addition to the debts already owed to Kit Fine, there are still two more to add. One debt is personal. Kit has been a continual source of encouragement, inspiration, and support to me during the editing of this volume as well as throughout my academic career. Thanks, Kit. The other debt is philosophical.Without the background of Kit’s pioneering work on ground, one struggles to imagine there being an art in a state worth surveying.

xviii

INTRODUCTION

Michael J. Raven

Some of philosophy’s biggest questions are in-virtue-of questions. Examples include: In virtue of what is a society just or unjust? In virtue of what does a sentence mean what it does? In virtue of what does someone possess knowledge? In virtue of what is an action good or bad? In virtue of what is a creature conscious? In virtue of what is an artwork beautiful? In virtue of what is something in motion? Many more examples could easily be given.These in-virtue-of questions are also among philoso­ phy’s oldest.Attempts to answer them stretch back to antiquity.And in-virtue-of questions are also among philosophy’s most enduring. Philosophers still try to answer them today. Their focus is usually on answering particular in-virtue-of questions rather than on the kind of question being asked. But in the new millennium, philosophers have increasingly focused on what an in-virtue-of question is in the first place. Philosophers increasingly assume, at least as a working hypothesis, that in-virtue-of questions involve a distinctively metaphysical kind of determinative explanation. This determinative explanation is sometimes expressed using phrases like ‘because’ or ‘consists in’. But the phrase that is currently most fashionable is ‘metaphysical ground’, or just ‘ground’ for short.1 Interest in ground swells; not just for its indirect role in formulating some of philosophy’s most venerable questions but also for the interest in questions that are directly about it. The purpose of this Handbook is to survey the state of the art on ground.There are already a few anthologies focusing on ground and related topics.2 But their emphasis is on original research, and their target audience is experts. By contrast, this Handbook focuses on surveying the literature on ground for newcomers and experts alike. The target audience thus includes students at the advanced undergraduate and graduate levels as well as professional philosophers. The Handbook adopts a dual perspective. It looks backward at where the literature has gone, and it looks forward to where it is going. Looking backward, the literature has rapidly expanded in the last decade or so. It shows no signs of slowing. Even experts have trouble keeping pace. There is thus a need for a backward-looking resource cataloging where the literature is and has been. Looking forward, the literature is in a state of rapid, ongoing development.Although some 1

Michael J. Raven

consensus is emerging, many matters remain in flux. Terminology is unregimented. Formula­ tions vary. Controversies abound.There is thus a need for a forward-looking resource assessing where future research should be directed.The Handbook is meant to provide both resources. This introduction has two aims.The first aim is to provide a primer on ground. Section 1 gives a crash course on how ground is commonly conceived. Although many aspects of this conception are controversial, it nevertheless prevails in the literature.Those already familiar with the literature should have no trouble recognizing this conception from it. And those unfamiliar with the literature should get enough from the primer to profitably read the essays to follow. The second aim is to provide an overview of the Handbook. Section 2 gives a brief description of how the Handbook’s 37 original essays are organized around five major themes. It also gives a brief history of the origins of the Handbook and how collaborative research among its contribu­ tors produced it.

1. Primer Some philosophical topics are familiar from everyday life. These topics include justice, meaning, knowledge, goodness, consciousness, beauty, and motion, to name just a few. Topics like these can be easily seen in the history of philosophy (even when their histories are murky). But things are different for the notion of ground. Unlike the familiar topics above, ground is unlikely to be familiar outside of academic philosophy. And at least until recently, ground—at least under that name—was unfamiliar even within academic philosophy.What is this notion of ground? We may distinguish two broad approaches to answering this question.An approach from below collects examples of ground’s potential applications and extrapolates from them what ground is. An approach from above surveys ground’s theoretical role together with its connections to other theoretical notions and triangulates from them what ground is. It needn’t be supposed that these are the only approaches to characterizing ground. But they seem to be the most prevalent. Approached from below, ground is extrapolated from its potential applications to vari­ ous topics. The possible topics and the potential applications to each are too numerous to list exhaustively. So a smaller sample must be selected from the many options.This runs the risk of extrapolating from a poorly chosen sample. But the risk can be mitigated by selecting a broad and diverse sample.To illustrate, here are nine possible topics, each with a representative claim of ground: Identity The identity of two sets is grounded in the identities of their members. Law of Metaphysics Instances of the laws of metaphysics are grounded in the laws of metaphysics. Law of Nature The laws of nature are grounded in patterns of local, qualitative matters of fact. Logic The ball is red and round because it is red and it is round. Mind Someone’s being in pain is grounded in their firing c-fibers. Normativity The rightness of an action is grounded in its maximizing utility. Physicalism All nonphysical facts are grounded in physical facts. Semantics That a fact obtains grounds the truth of a sentence expressing that fact. Social Entities That a person is a citizen is grounded in their occupying a certain social role. Each of these statements makes a claim about what grounds what. None of these ground claims is uncontroversial. But each illustrates a potential application of ground to some topic. None of these potential applications is uncontroversial either. Indeed, there is a great deal more to say 2

Introduction

about each of these potential applications (Part III).Yet despite their many differences, we may still recognize an abstract similarity. Each seems to be asking a question of explanation. Not just any sort of explanation is at issue. It is not, for instance, causal explanation. Instead, the sort of explanation seems to be distinctively determinative or constitutive.What is explained is determined by or constitutively depends on what explains it (Chapters 7 and 8). Extrapolating provides a conception of ground from below. Approached from above, ground is triangulated from its role and its connections to other notions. These connections form a vast and intricate landscape of similarities and differences. Zooming in provides a detailed view of the specifics local to a connection. Zooming out provides a panoramic view of the general contours of the global landscape. These contours are shaped by a grand organizing idea characteristic of ground. It is a stratified or hierarchical picture of reality. The details of the picture can be developed in various ways. An especially common version of the picture divides reality into levels. Some levels depend on or otherwise derive from others (Chapter 7). Perhaps the psychological level derives from the neurochemical level, or the chemical level derives from the physical level. Perhaps there is even a foundational level that derives from no others but from which all other levels derive. Or perhaps there is no foundation, just levels all the way down (Chapter 16). Whichever it is, ground’s characteristic role is to stratify what levels there are. For the psychological level to derive from the neurochemical level is for the facts of the neurochemical level to ground the facts of the psychological level, and so on for other levels. There may and often will be causal connections between levels. Neurochemical causes might have psychological effects, and perhaps vice versa. But even when these causal connections induce stratifications of their own, they will not be the characteristic stratifications induced by ground. These are supposed to be induced by the distinctive kind of determinative explanation ground provides (Chapter 8). The result is a hierarchy of grounds. This hierarchical picture exerts at least some influence on ground’s connections to other notions. To illustrate, here are ten such notions often taken to be connected to ground in various ways and to various degrees: Analyticity Truths that hold solely in virtue of the meanings of the words used to express them. Cause An event or agent making happen another event. Emergence Novel facts, items, properties, or phenomena that somehow arise from others while being irreducible to them. Essence What it is for some item to be the very item that it is, or the properties that such an item has by its nature. Fundamentality What is basic and that from which the nonbasic derives. Modality Possibility, impossibility, necessity, contingency, and related notions, such as supervenience. Ontology What there is or what exists. Realism What is real or holds in reality, as opposed to what is merely apparent. Structure The distinguished or “joint-carving” aspects of reality. Truth-making The relation between a true representation and what it represents and in virtue of which it is true. None of these potential connections is entirely straightforward or uncontroversial. Indeed, there is a great deal more to say about each (Part IV). But together these connections help to locate ground’s position on the theoretical landscape. Triangulating provides a conception of ground from above. 3

Michael J. Raven

The dual approaches differ in their trajectory. On the approach from below, ground is extrapo­ lated from its potential applications. On the approach from above, ground is triangulated from its theoretical role and connections. One might reasonably wonder whether these trajectories con­ verge on the same target notion. Perhaps there are various distinct ground-like notions (Chap­ ter 13). But even if there are various ground-like notions, it might still be that the trajectories converge on one of them. Just as philosophers have become accustomed to a single3 notion of cause involved in how some events (or agents) produce others, so too it is perhaps not much of a leap to accept a single notion of ground involved in how some facts consist in or hold in virtue of others. Much of the literature assumes, at least as a working hypothesis, that there is indeed a notion of ground at the convergence point of the dual approaches from above and from below. The dual approach makes ground clearly visible in the history of philosophy. Questions of ground trace back to antiquity (Chapter 1). Our contemporary notion of ground has much in common with Aristotle’s notion of demonstration (Chapter 2). Questions of ground continued to be discussed in the medieval and modern periods (Chapter 3), perhaps most prominently as they engaged with the principle of sufficient reason (Chapter 4). Even so, it has been only relatively recently that ground has been treated as a topic of investigation in its own right.4 Bolzano’s pioneering work on ground was ahead of its time (Chapter 5) and influenced ground’s role in the Austro-Germanic phenomenological tradition (Chapter 6). The anti-metaphysical sentiments of much of the 20th century resulted in little work directly on ground. But recent interest in ground was kickstarted by a trio of influential articles (Fine 2001; Schaffer 2009; Rosen 2010) soon followed by an anthol­ ogy (Correia & Schnieder 2012). Since then, ground has become a hot topic.Articles are regularly published exploring it and its applications.And ground has suffused into many parts of philosophy. The dual approach also provides guidance on what ground’s characteristic features might be. For we may identify many of ground’s characteristic features by attending to its intended role in its potential applications and from its potential connections to other notions. None of these fea­ tures are beyond all controversy. Indeed, some have been challenged vigorously in the literature. So these features should not be regarded as definitive of what ground is. Even so, they may still be used to help illuminate what ground is supposed to be.These features may collectively aim at their intended target, even if the target does not have them all.This way of fixing on a topic is not altogether unfamiliar. It is perhaps somewhat like how a definite description (‘the person drinking the martini’) may be used to refer to an individual that does not satisfy the description (there is only water in the martini glass).5 With this as our inspiration, we may introduce ground’s characteristic features by developing an extended example.A bartender fills a mixing glass with ice.After measuring some ingredients (gin, dry vermouth), they are poured and mixed in the mixing glass.The result is poured into a coupe glass and garnished with an olive.The bartender has made a beverage, a martini.A martini is a distinctive kind of beverage. Unlike fresh-squeezed orange juice or straight gin, a martini is a mixed drink. Unlike other mixed drinks such as a lassi or a latte, a martini is alcoholic.These two features determinatively explain the martini’s being a cocktail: (1) This martini is a cocktail because it is alcoholic and mixed.6 We may say this using the terminology of ‘ground’ instead: (2) That this martini is alcoholic and mixed grounds the fact that it is a cocktail. Call a claim of the form ‘. . . grounds __’ a ground claim.What fills in the ‘. . .’ are the grounds. What fills in the ‘__’ is the grounded. Ground claims are usually taken to be many–one. Any nonnegative 4

Introduction

number of grounds may fill in the ‘. . .’, but only a single grounded item may fill in the ‘__’.There is a less common and more general many–many (or bicollective) formulation which allows a non­ negative number of grounds or grounded items on both sides (Dasgupta 2014; Litland 2018). But our focus, along with most of the literature, will be on the usual many–one formulation. Although a ground claim is not a conditional in the usual sense, it does state a kind of deter­ minatively explanatory sufficient condition. The grounds determinatively explain, and therefore suf­ fice for, what they ground.7 This suggests that the terminology of ‘antecedent’ and ‘consequent’ familiar from conditionals may be adapted to ground claims.Thus, given the ground claim ‘A, . . . grounds C,’ we may refer to the grounds collectively as the antecedents (A, . . .) and to what is grounded as the consequent (C).This terminology is nonstandard. But it allows handy mnemonics (‘A’ for antecedents, ‘C’ for consequent) while avoiding alliterative awkwardness (cf. “the ante­ cedents ground the consequent” vs. “the grounds ground the grounded”). Nevertheless, both terminologies have their place. I will switch between them as convenient. The literature contains several competing notations for ground claims.The three most com­ mon use three different symbols for ground: a reverse arrow ‘←’ (Rosen 2010), an inequality symbol ‘ 2’.The same analogously holds for ‘ This martini is alcoholic and mixed (2c’) This martini is a cocktail  This martini is alcoholic and mixed Neither (2a’) nor (2c’) are usually taken to be ground claims: (2a’) looks like a conditional, whereas (2c’) is an essentialist claim (in Fine 2015’s notation).8 But (2b) and (2b’) are the same ground claim, differently expressed. Thus, only ‘