Gigerenzer - Rationality for Mortals. How People Cope with Uncertainty

Rationality for Mortals

General Editor: Stephen Stich, Rutgers University

PUBLISHED IN THE SERIES

Simple Heuristics That Make Us Smart

Gerd Gigerenzer, Peter Todd, and the ABC Research Group

Natural Selection and Social Theory: Selected Papers of Robert Trivers

Robert Trivers

Adaptive Thinking: Rationality in the Real World

Gerd Gigerenzer

In Gods We Trust: The Evolutionary Landscape of Religion

Scott Atran

The Origin and Evolution of Cultures

Robert Boyd and Peter J. Richerson

The Innate Mind: Structure and Contents

Peter Carruthers, Stephen Laurence, and Stephen Stich

The Innate Mind, Volume 2: Culture and Cognition

Peter Carruthers, Stephen Laurence, and Stephen Stich

The Innate Mind, Volume 3: Foundations and the Future

Peter Carruthers, Stephen Laurence, and Stephen Stich

Why Humans Cooperate: A Cultural and Evolutionary Explanation

Natalie Henrich and Joseph Henrich

Rationality for Mortals: How People Cope with Uncertainty

Gerd Gigerenzer

How People Cope with Uncertainty

Gerd Gigerenzer

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First issued as an Oxford University Press paperback, 2010

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Library of Congress Cataloging-in-Publication Data
Gigerenzer, Gerd.
Rationality for mortals : how people cope with uncertainty / Gerd Gigerenzer.
p. cm. (Evolution and cognition)
Includes bibliographical references and index.
ISBN 978-0-19-974709-2
1. Reasoning (Psychology) 2. Thought and thinking. I. Title.
BF442.G54 2008
153.4'3dc22 2007029644

9 8 7 6 5 4 3 2 1
Printed in the United States of America
on acid-free paper

This book is a collection of essays on rationality, risk, and rules of thumb and is a sequel to an earlier volume, Adaptive Thinking: Rationality in the Real World (Oxford University Press, 2000). The essays, which have been edited and updated with new material, focus on heuristic and statistical thinking. These are complementary mental tools, not mutually exclusive strategies; our minds need both. This interplay between these two modes of thinking will become evident in the course of the book. Beforehand I would like to point out some principles of the research philosophy underlying this collection of papers.

1. Topic-oriented rather than discipline-oriented research. There are two ways to do social science: One is to be curious about a topic (such as the rationality of rules of thumb) and to assemble a group of researchers who approach it from different disciplines, methodologies, and theories. The second is to identify with a discipline or subdiscipline (such as social psychology) and to research topics only within its confines. I would say that most of psychology practices the discipline-oriented version of science; in many departments the cognitive wing rarely speaks with the developmental wing, the personality unit sees little merit in the evolutionary psychologists, and vice versa. Such territorial behavior is a huge obstacle to progress in the field. In this tradition, there is little curiosity or even awareness as to what other disciplines know about the same topic, and, at worst, one looks down at everyone else as either inferior or at best irrelevant. When Peter M. Todd and I founded the Center for Adaptive Behavior and Cognition (ABC) in 1995, we followed a deliberately topic-oriented research program. Not only psychologists from different subdisciplines talk, work, and publish together at the center, but also economists, computer scientists, mathematicians, engineers, behavioral biologists, political scientists, philosophers, and anyone else who is curious about our common topic: How do people make decisions when time and information is limited, and the future uncertain? The papers on which this volume is based were published in psychological, economic, educational, medical, and philosophical journals or books and are herewith made more easily accessible. Important topics do not respect the historically grown disciplinary borders, and if we strive for exciting knowledge rather than a comfortable career, we need to be in love with the topic, not with our professional in-group.

2. Multiple methodologies. Science has not one method, but many. These include observation in the natural world, experimentation in the laboratory, mathematical proof, computer simulation with real data, analysis of surveys and demographical statistics, and thought experiments for the great geniuses, such as Galileo and Einstein. In the social sciences, a climate of anxious identification with a subdiscipline goes hand in hand with methodological rituals. Sociologists tend to rely on multiple regression analyses of survey and demographic data and show little interest in other methods; experimental psychologists have largely reduced their methodological imagination to running laboratory experiments and checking significance levels; educational researchers tend to compute structural equation models whether their assumptions hold or not; and economists excel in mathematical proofs, scorning those mathematical innumerates who have no skills apart from running experiments. Methodological uniformity and discipline-oriented research are two sides of the same coin. In contrast, topic-oriented research can free us from the straightjacket of methodological rituals, allowing us to consider and choose proper methodologies for the problem at hand and to verify a result obtained with one method by using other methods.

3. Mix of real-world and laboratory studies. Science does not only take place in the laboratory. To determine what laboratory research tells us about the world, we need to check with the outside world, and to determine whether our observations in the world are correct, we need to test them in the laboratory. A good mix is indispensable. Otherwise, we run the danger of growing so obsessed with the zillionth variation on a toy problem that we can no longer say how it relates to the world outside the lab.

Each of these three principles creates heterogeneity. Together, they can provide a momentum for research that is creative, innovative, and enjoyable. Many believe that interdisciplinary research is unrewarding and exhaustingly time consuming because one needs to learn a common language and deal with naive questions, only for everyone to soon return to the safe haven of their home disciplines. Fortunately, none of that has been my experience.