Why what we know isn't necessarily so

Don't Believe Everything You Think: The 6 Basic Mistakes We Make in Thinking. By Thomas Kida. Prometheus Books, Amherst, New York, 2006. ISBN 1-59102-408-0. 286 pp. Paperback, $19.

In Don't Believe Everything You Think, Thomas Kida describes the main ways by which we arrive at false beliefs, which in turn lead us to make decisions that are harmful not only to ourselves but to society. Concerning the latter, for example, public officials spent around $10 billion in the 1990s to eliminate asbestos from public buildings. Asbestos may be dangerous if inhaled, but its wholesale removal from buildings was based on the erroneous belief that its mere presence in building materials was in every case a serious health hazard. In fact, however, its removal is often more dangerous than leaving it in place.

The importance of critical thinking is one of the main topics of former Harvard President Derek Bok's recent book Our Underachieving Colleges. And most of the content of Levitt and Dubner's wildly popular Freakonomics is the result of the authors' critical thinking about various contemporary topics. But, says Kida, critical thinking and decision-making are typically not taught in our schools.

Kida's book is a primer to help us avoid obstacles to critical thinking and decision-making. Kida presents us with what he labels "our six pack of problems." The first problem is that we prefer stories to statistics. But relying on anecdotal evidence to form our beliefs and make our decisions can result in serious errors because we ignore other relevant information. Much of this other information is statistical. The problem is exacerbated by the news media's reliance on anecdotal evidence. The news media often present us with gripping personal stories without addressing whether they are representative of many other individuals.

Another problem is that we seek to confirm--not question--our ideas (psychology's "confirmation bias"). We look for, and remember better, information that supports our beliefs while we ignore or discount information that would undermine or contradict our beliefs.

We also rarely appreciate the role of chance and coincidence in life. We often believe that we see causes for events that are in fact random, or simply the result of chance occurrences.

Erroneous beliefs are sometimes caused by misperceptions of our world. What we see is not always an accurate record of external reality. Our perceptions are strongly influenced by what we expect (and want) to see and hear.

Sometimes the amount of information confronting us is overwhelming, so we use a number of simplifying strategies. Such strategies can save us time and effort and enable us to make decisions quickly. But if we oversimplify and ignore important information, we can make costly inaccurate judgments.

Human memory is far from a permanent record of our past experiences. Not only do our memories change over time, we can create new memories for events that never actually happened. Our current beliefs, expectations, and suggestive questioning can strongly influence our memories of past events. In light of this it's more accurate to think of memory as a reconstruction of the past.

Unfortunately, Kida notes, we are typically not even aware that these basic mistakes in thinking exist. In addition to the six pack of problems, Kida briefly considers such issues as 20/20 hindsight, intuitive judgments, and the influence of others, including groupthink.

This is an informative, interesting, and entertaining contribution that includes many examples of the mistakes that Kida addresses. He goes beyond simply describing our false beliefs to describing the ways in which we acquire them. For many decades educators at all levels have extolled the value of teaching critical thinking. But just how extensive and effective are such efforts? This book is a valuable resource in the ongoing, difficult process of developing critical thinking.

Peter Lamal is emeritus professor of psychology at the University of North Carolina-Charlotte and a Fellow of the Division of Behavior Analysis of the American Psychological Association.

COPYRIGHT 2006 Committee for the Scientific Investigation of Claims of the Paranormal
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