Argumentação

How to Win Every Argument
The Use and Abuse of Logic

Also available from Continuum What Philosophers Think - Julian Baggini and Jeremy Stangroom What Philosophy Is - David Carel and David Gamez Great Thinkers A-Z - Julian Baggini and Jeremy Stangroom

How to Win Every Argument
The Use and Abuse of Logic
Madsen Pirie

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• • • L O N D O N • NEW YORK

To Thomas, Samuel and Rosalind

Continuum International Publishing Group The Tower Building 11 York Road London SE1 7NX © Madsen Pirie 2006

15 East 26th Street New York, NY 10010

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. Madsen Pirie has asserted his right under the Copyright, Designs and Patents Act, 1988, to be identified as Author of this work British Library Cataloguing-in-Publication Data A catalogue record for this book is available from the British Library. ISBN: 0826490069 (hardback) Library of Congress Cataloguing-in-Publication Data A catalog record for this book is available from the Library of Congress. Typeset by YHT Ltd, London Printed and bound in Great Britain by MPG Books Ltd, Bodmin, Cornwall

Contents

Acknowledgments Introduction Abusive analogy Accent Accident Affirming the consequent Amphiboly Analogical fallcy Antiquitam, argumentum ad Apriorism Baculum, argumentum ad Bifurcation Blinding with science The bogus dilemma Circulus in probando The complex question (plurium interrogationum) Composition Concealed quantification Conclusion which denies premises Contradictory premises Crumenam, argumentum ad Cum hoc ergo propter hoc Damning the alternatives

viii ix 1 3 5 7 9 11 14 15 17 19 22 24 27 29 31 33 35 38 39 41 44

VI

How to Win Every Argument

Definitional retreat Denying the antecedent Dicto simpliciter