Why We Make Mistakes: How We Look Without Seeing, Forget Things in Seconds, and Are All Pretty Sure We Are Way Above Average
Joseph T. Hallinan
Broadway Books, Reprint edition (2010)

And why we often make mistakes when trying to understand mistakes

Frankly, until reading this book, I assumed that I understood why people make mistakes. True, several of the causes are obvious: emotional, impulsive decisions made in haste, action without sufficient knowledge, trust in unreliable sources, false assumptions or premises, and so forth. However, most people are vulnerable to basic illusions and/or delusions. (Check out the tabletops illustration devised by Roger Shepard on Page 20.) As John Hallinan explains so brilliantly in this book, most of the most significant causes are not so obvious and one of them really caught my attention: even when we know we have made a mistake, we reject that fact and often make the same mistake again. Why? Because “we are all afflicted with certain systemic biases in the way we see, remember, and perceive the world around us, and these biases make us prone to commit certain kinds of errors…we just don’t know we’re biased. Some of these tendencies are so strong that even when we do know about them, we find it hard [if not impossible] to correct for them.” Here is a representative selection of phenomena, observations, and insights:

“Understanding the role of context is also extremely important, especially when it comes to remembering things. Memory, it turns out, is often more a reconstruction than a reproduction.” (Page 9)

“In one study, radiologists missed up to 90 percent of cancerous tumors that, in retrospect, had been visible `for months or even years.'” (Page 24)

“If we are going to err at something, we would rather err by [begin italics] failing [end italics] to do something.” (Page 53)

“It doesn’t take much to distract a driver. A two-second glance doubles the risk of an accident.” (Page 83)

Note: My first reaction to this item was “So what? What’s the big deal?” Then I did a simple calculation and realized that if a car were moving at 60 mph, it would travel 176 feet in only two seconds. Hmmmm….

“As something becomes more familiar, we tend to notice less, not more. We come to see things not as they are but as (we assume) they ought to be.” (Page 113)

“Events learned in one emotional state are best remembered when we are back in that happy state. Happy times, for instance, are best remembered when we’re happy.” (Page 117)

“We often think we’re being rational when we’re being visceral, and vice versa. When a mistake does happen, we often end up blaming the wrong cause.” (Page 211)

“Happy people tend to be more creative problem solvers. They also make decisions more quickly, with less back-and-forth.” (Page 218)

Many readers may not be aware of the neurological infrastructure of the decision-making process, notably the importance of what is generally referred to as the “unconscious mind.” That is what Hallinan means when noting that many decisions are made or at least significantly influenced “outside of our consciousness.” This fact helps to explain why most of us make mistakes when trying to understand why we make mistakes. Ironically, we demonstrate what we are trying to eliminate.

As indicated by hundreds of citations throughout the book supplemented by extensive References and Bibliography section (Pages 225-237 and Pages 239-273), Hallinan has obviously absorbed and digested an abundance of research data from a wide range of resources. He fully achieves his objective to explain why people make mistakes of all kinds and suggests, especially in the concluding chapter, what can be done to prevent or correct them. He urges his readers to “Think small [because] little things, as the song says, mean a lot.” Also, be alert to the fact that “we don’t see all that we observe, and yet we sometimes ‘see’ things we don’t know we’ve seen.” Therefore, beware of seeing only what you expect to see, not what is. Certain biases such as overconfidence (i.e. hubris) are amenable to correction. On occasion, it also helps to think negatively when making a decision. “What could go wrong?” Hallinan also suggests we can become less error prone by letting our spouse “proofread” our reasoning and by slowing down and sharpening the focus of our attention. “Multitasking is, for most of us, a mirage. There are strict limits to the number of things we can do at one time, and the more we do [or attempt to do], the greater the chance for error.”

Many who read this last paragraph may respond, “Well, duh, that’s just common sense.” As Joseph Hallinan convincingly establishes in this thoroughly entertaining as well as highly informative book, it would be a serious mistake to assume that common sense is common.