"This book is a landmark in both content and style of argument. It is a major advance in our understanding of expert judgment in the vitally important and almost impossible task of political and strategic forecasting. Tetlock also offers a unique example of even-handed social science. This may be the first book I have seen in which the arguments and objections of opponents are presented with as much care as the author's own position."--Daniel Kahneman, Princeton University, recipient of the 2002 Nobel Prize in economic sciences<P>"This book is a major contribution to our thinking about political judgment. Philip Tetlock formulates coding rules by which to categorize the observations of individuals, and arrives at several interesting hypotheses. He lays out the many strategies that experts use to avoid learning from surprising real-world events."--Deborah W. Larson, University of California, Los Angeles<P>"This is a marvelous book--fascinating and important. It provides a stimulating and often profound discussion, not only of what sort of people tend to be better predictors than others, but of what we mean by good judgment and the nature of objectivity. It examines the tensions between holding to beliefs that have served us well and responding rapidly to new information. Unusual in its breadth and reach, the subtlety and sophistication of its analysis, and the fair-mindedness of the alternative perspectives it provides, it is a must-read for all those interested in how political judgments are formed."--Robert Jervis, Columbia University<P>"This book is just what one would expect from America's most influential political psychologist: Intelligent, important, and closely argued. Bothscience and policy are brilliantly illuminated by Tetlock's fascinating arguments."--Daniel Gilbert, Harvard University

Philip E. Tetlock is Mitchell Professor of Leadership at the University of California, Berkeley. His books include "Counterfactual Thought Experiments in World Politics" (Princeton).

Acknowledgments ix

Preface xi

Chapter 1: Quantifying the Unquantifiable 1

Chapter 2: The Ego-deflating Challenge of Radical Skepticism 25

Chapter 3: Knowing the Limits of One's Knowledge: Foxes Have Better Calibration and Discrimination Scores than Hedgehogs 67

Chapter 4: Honoring Reputational Bets: Foxes Are Better Bayesians than Hedgehogs 121

Chapter 5: Contemplating Counterfactuals: Foxes Are More Willing than Hedgehogs to Entertain Self-subversive Scenarios 144

Chapter 6: The Hedgehogs Strike Back 164

Chapter 7: Are We Open-minded Enough to Acknowledge the Limits of Open-mindedness? 189

Chapter 8: Exploring the Limits on Objectivity and Accountability 216

Methodological Appendix 239

Technical Appendix: Phillip Rescober and Philip E. Tetlock 273

Index 313