ARGUING WELL Argument is the primary way of discovering the truth and thinking freely for ourselves. But just knowing how to reason well is not enough to ensure that we do so because often factors seduce us away from reasoning well or at all. Arguing Well is a lucid introduction to the nature of good reasoning, how to test and construct good arguments. It assumes no prior knowledge of logic or philosophy. The book includes an accessible introduction to basic symbolic logic. The book is ideal for any student embarking on academic study where arguments are what matter, in fact for all people who want to understand the nature and importance of good reasoning and awaken their ability to argue well. John Shand is an Associate Lecturer in Philosophy at The Open University. He is the author of Philosophy and Philosophers: An Introduction to Western Philosophy (1994). ARGUING WELL John Shand London and New York TO JUDI WITH LOVE First published 2000 by Routledge 11 New Fetter Lane, London EC4P 4EE Simultaneously published in the USA and Canada by Routledge 29 West 35th Street, New York, NY 10001 Routledge is an imprint of the Taylor & Francis Group © 2000 John Shand Typeset in Sabon by Keystroke, Jacaranda Lodge, Wolverhampton Printed and bound in Great Britain by Clays Ltd, St Ives pic 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. British Library Cataloguing in Publication Data A catalogue record for this book is available from the British Library Library of Congress Cataloging in Publication Data Shand, John, 1956- Arguing well / John Shand. p. cm. Includes bibliographical references. 1. Reasoning. I. Title. BC177 .S45 2000 168—dc21 00-020475 ISBN 0-415-16685-3 (hbk) ISBN 0-415-16686-1 (pbk) Logic of itself cannot give anyone the answer to any question of substance; but without logic we often do not know the import of what we know and often fall into fallacy and inconsistency. Peter Geach Learning to infer is not just a matter of being taught about explicit logical relations between propositions; it is learning to do something. Peter Winch Thus Reason works itself out of the chains of dogma, of caprice, of arrogance, of passion. ... It knows it is lost if it clutches prematurely at a part of the truth and makes it the ultimate absolute truth ... it must not leave out anything, must not drop anything, exclude anything. It is itself a boundless openness. . . . Reason is like an open secret that can become known to anyone at any time; it is the quiet space into which everyone can enter through his own thought. Karl Jaspers To be clear-headed rather than confused; lucid rather than obscure; rational rather than otherwise; and to be neither more, nor less, sure of things than is justifiable by argument or evidence. That is worth trying for. Geoffrey Warnock CONTENTS Preface viii 1 Introduction 1 Rationale 3 20 2 Arguments 3 How arguments fail 39 4 Definitions 46 5 Basic symbolic logic 58 6 Understanding reason is not enough 86 Further reading 99 Index 102 Vll PREFACE This book grew from a wish to give people the tools, both logical and psychological, that would enhance their reasoning and prevent them from abandoning reason, or applying it poorly, when applying it and applying it well is what they should be doing. Too many terrible consequences have followed throughout human history for this not to be important. Even regardless of that, reasoning is necessary for us to take control so that the kind of life we have is our genuine choice. This is only the beginning of course; the hard work comes in applying some of the precepts in this book. But without them, however you end up, you will be a sort of slave, not a freethinker. Anything else belittles us as human beings. There is no guarantee that such thinking will make you happier, but it can strengthen your integrity, and enhance a noble feature of human beings. It also builds on the unique capacity of human beings to reflect on themselves and the world. Here, integrity means trying to make one's beliefs hang together consistently and being determined to search for and face the truth even when we may wish the truth otherwise. Open argument is vital to this. I am of course in the debt of several people who helped me with writing this book. In particular I should like to thank my wife Judith Shand, Sue Ashford, Michael Clark and Jay Kennedy; also the anonymous readers appointed by Routledge who commented on the manuscript. All remaining errors are strictly my responsi- bility. vin