Evidential Reasoning in Archaeology Debates in Archaeology Series editor: Richard Hodges Against Cultural Property, John Carman The Anthropology of Hunter Gatherers, Vicki Cummings Archaeologies of Conflict, John Carman Archaeology: The Conceptual Challenge, Timothy Insoll Archaeology and International Development in Africa, Colin Breen and Daniel Rhodes Archaeology and the Pan-European Romanesque, Tadhg O’Keeffe Archaeology and State Theory, Bruce Routledge Archaeology and Text, John Moreland Beyond Celts, Germans and Scythians, Peter S. Wells Building Colonialism, Daniel T. Rhodes The Byzantine Dark Ages, Michael J. Decker Combat Archaeology, John Schofield Debating the Archaeological Heritage, Robin Skeates Early European Castles, Oliver H. Creighton Early Islamic Syria, Alan Walmsley Fishing and Shipwreck Heritage, Sean A. Kingsley Gerasa and the Decapolis, David Kennedy Image and Response in Early Europe, Peter S. 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All rights reserved. No part of this publication may be reproduced or transmitted in any form or by any means, electronic or mechanical, including photocopying, recording, or any information storage or retrieval system, without prior permission in writing from the publishers. No responsibility for loss caused to any individual or organization acting on or refraining from action as a result of the material in this publication can be accepted by Bloomsbury or the authors. British Library Cataloguing in Publication Data A catalogue record for this book is available from the British Library. ISBN: HB: 978-1-4725-2527-7 ePDF: 978-1-4725-3469-9 ePub: 978-1-4725-2893-3 Library of Congress Cataloging-in-Publication Data A catalogue record for this book is available from the Library of Congress Series: Debates in Archaeology Cover image: Working with Old Evidence: Insula IX of the Roman town of Silchester, excavated in 1893 by the Society of Antiquaries (bottom left, reproduced by permission of Reading Museum), and re-excavated from 1997 (images by Alison Wylie, right, and by permission of Michael Fulford and Amanda Clarke, top left). Typeset by Fakenham Prepress Solutions, Fakenham, Norfolk NR21 8NN Contents List of Illustrations vi Acknowledgements viii Introduction: The Paradox of Material Evidence 1 1 Archaeological Evidence in Question: Working between the Horns of a Dilemma 15 2 Archaeological Fieldwork: Scaffolding in Practice 55 3 Working with Old Evidence 93 4 External Resources: Archaeology as a Trading Zone 143 Conclusions: Reflexivity Made Concrete 203 Bibliography 217 Index 243 List of Illustrations Table 4.1 Comparison of proposed origins for individuals in the later Roman cemetery at Lankhills School, Winchester, based on archaeological and isotope analyses. 189 Figures All artwork created by the authors. 1.1 Toulmin’s argument schema: components and conditions. 34 1.2 A generic archaeological example of an evidential argument. 35 2.1 Plan of 1938–9 excavations at Little Woodbury, showing timber houses, as well as more than one phase of ‘overlapping and intersecting features’. 64 2.2 Little Woodbury in relation to Greater Woodbury and features of the surrounding landscape identified by aerial photography. 66 2.3 Conflicting evidential arguments: Collingwood and Bersu on excavated features at King Arthur’s Round Table. 70 2.4 Example of a single-context recording sheet. 78 2.5 Example of a schematic matrix representing the stratigraphic sequence in trench 1 at Gatas in south-east Spain. 79 3.1 Glastonbury Iron Age village, floor ii, mound LXXIV, showing baked clay hearth. 109 3.2 Glastonbury Iron Age village, section of superimposed hearths of mound LXXIV. 110 List of Illustrations vii 3.3 Glastonbury Iron Age village, timber substructure and palisade south-west of mound V. 110 3.4 Clarke’s modular unit for Glastonbury Iron Age village. 114 3.5 (Left) Clarke’s proposed Phase IV structures for Glastonbury Iron Age village; (Right) Clarke’s ‘tentative social model of the structural pattern’ for his Phase IV of Glastonbury Iron Age village. 115 3.6 Glastonbury Iron Age village, North–South section through the middle of mound XIII. 123 3.7 Comparison of (left) Clarke’s ‘speculative’ environmental reconstruction of the Glastonbury Iron Age village territory and (right) Aalbersberg and Brown’s most recent palaeoenvironmental reconstruction. 128 3.8 The search for non-random patterning in Bulleid and Gray’s ‘amorphous agglomeration’ of features at Glastonbury. 132 4.1 The Childers site chronology: multiple lines of evidence with diverse warrants and backing. 153 4.2 Distribution of copper oxhide ingots and ingot mould in the central and east Mediterranean. 167 4.3 Lead isotope analysis of oxhide ingots from Sardinia and the Apliki copper ore source in Cyprus. 173 4.4 Lead isotope analysis: evidential arguments constrained by multiple rebuttals. 176 Acknowledgements The planning for this book and for its companion, the edited volume Material Evidence: Learning from Archaeological Practice (Routledge, 2015), began in 2010, when a grant from the Leverhulme Trust, sponsored by Bob Chapman, made it possible for Alison Wylie to spend six months as a Visiting Professor in the Department of Archaeology at the University of Reading (UK). We thank the Leverhulme Trust and the staff and postgraduate students of the Department of Archaeology for their support, as well as the University of Washington for granting the leave that made this extended visit at Reading possible. We also thank colleagues in the many departments of Archaeology and of Philosophy in the UK who hosted Leverhulme lectures and seminars in 2010, and the colleagues who participated in a workshop on ‘Material Culture as Evidence’ that we convened in Reading in June 2010. This workshop was made possible by generous support from the Leverhulme Trust and the then School of Human and Environmental Sciences at the University of Reading. The feedback on these lectures, and the discussions generated by the workshop and a seminar series on evidential reasoning that we convened in the Department of Archaeology at the University of Reading, were crucial to shaping our vision for these two collaborative ‘evidence’ projects: Material Evidence and now Evidential Reasoning in Archaeology. We especially thank Richard Bradley, Mike Fulford and Gundula Müldner for presenta- tions in the Reading seminars, and all the contributors to the Reading workshop and to Material Evidence for incisive analyses and inspiring examples of archaeology-in-practice that pushed our thinking about evidential reasoning in more ways than we can credit. Alison Wylie thanks, as well, her Archaeology colleagues at the University of Washington for a vigorous and enormously helpful discussion of a FAALS presentation she gave on the Leverhulme ‘Evidence’ project when she returned from Reading (Friday Afternoon Archaeology Acknowledgements ix Lecture Series), and her CHESS (Centre for Humanities Engaging Science and Society) colleagues at the University of Durham for rigorous debate about ‘robustness’ reasoning and the inspiring example they set as philosophers of science actively engaged with science practice and policy. In the course of writing this book we realized that we were not alone in our frustration with the positions and debates we characterize as dead ends in thinking about evidential reasoning, and that many of our intuitions about more promising alternatives had been articulated by intellectual forebears who, to varying degrees, have been read out of our respective disciplinary canons. On the archaeology side, we have been particularly influenced by David Clarke’s advocacy in 1973 for building an ‘internal’ philosophy of archaeology, and inspired by the example he sets for integrating philosophical reflection into research practice. And on the philosophy side, we found in Stephen E. Toulmin’s brief for attending to the Uses of Argument (1958) an articulation of a philosophical stance that anticipates by several decades the pragmatic turn we hope is successfully embodied in our case-grounded analyses of evidential reasoning in archaeology. Finally, we thank Martin Bell for suggesting we submit this book to the Duckworth Debates in Archaeology series, the series editor Richard Hodges for his enthusiastic support, Richard Bradley for reading and offering constructive comments on drafts of Chapters 2 and 3, and Sarah Lambert-Gates and Rory Falconer for preparing the illustrations. Charlotte Loveridge and Alice Wright at Bloomsbury gave us encouragement and showed considerable patience with our several delays to the book’s completion. Any errors or omissions are our fault.