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Book Review: "Inevitable Illusions"

Vicky Tu's picture

 “The Eyes sees what it sees, even when we know what we know”(P17).

This sentence at the beginning of Chapter 1 leaves me a first big impression of this book because it almost summarizes the main idea of this book. Piattelli-Palmarini explains how humans naturally form cognitive illusions, how these illusions affect our decision-making, and some ways to improve this situation. By reading this book, I am actually frightened to see how unreliable our cognition actually is. In fact, it is the second time I get this shock. I first get this shock in class when we talked about how our eyes make-up images to fill our blind spots. Even though I have also learned from classes earlier that there is no absolute truth and we can all be biased at times. But I have never imagined that the unconscious part of our brain actually make up, or pre-install a “picture” in our mind instead of what is real without us knowing it. The points from this book can easily be linked to what we learned in classes because it is also about how our cognitive illusions can take us so much astray from the “truth”.

Piattelli-Palmarini uses many examples to demonstrate our weakness. I remember one of them most clearly: psychologists ask test subjects to estimate the weight of little cylinders of different sizes. It turns out that “what seems heavier to most of use is that which requires the greatest effort to lift or handle (even with just two fingers)…the scale is often not taken as authoritative” (23). Probably for many people who have read this book, this example is not that significant. But to me, it is very disturbing because it shows that humans can be so irrational that they cling their own impressions and reasoning and refuse even a source of actual fact. (In this case their own reasoning are their estimation of the weights. The source of “truth” is the scale.) The worse part is that these people probably do not realize they are being irrational at all because they have done, what they consider, rational reasoning by lifting the weights with only two fingers. This is just one experiment. No harm can come from cognitive illusions during an experiment. But during actual times of emergency and danger, making irrational mistakes without realizing can cause massive amount of loss. The decision-maker will be so sure of himself when making his incorrect yet fatal judgment call and no one will be able to stop him/her because he/she will be so sure of him/herself.

Even in an occasion not of a big decision-making, but of a normal person’s life, cognitive illusions can cause so much harm. I will use shy people as an example. Many shy people are shy because they are too self-conscious. When they are about to say anything or do anything, they often have “picture” pre-installed in their mind of everybody judging them and making fun of them already even though the truth is that nobody is judging them. People barely know them. These shy people’s cognitive illusions lead them to shy away from many social situations that might bring them great opportunities and eventually hurt their own causes.

Back to the book, my favorite chapter is Chapter 4, “Probability Illusions”. In this chapter, Piattelli-Palmarini explained the “mental tunnels” that lead people to form illusions and make irrational decisions. He divided these tunnels into 8 categories: “The Framing of Choices”(52), “Segregating Decisions”(57), “The Conjunction Effect”(64), “Not Touching Base Rates” (4), “Misplaced Causality”(77), “To the Bitter End” (80), “The Certainty Effect”(85) and “The Uncertainty Effect”(89). I will pick a couple of my favorite ones to examine in this review.

“The Framing of Choices” is basically about how choices are presented greatly affected a person’s judgment and decision-making. Two sentences can have exactly the same meaning, but people understand them differently because of the way they are put together. Piattelli-Palmarini used an excellent and classic example to demonstrate it. The two sentences he provides are: A. “If a (certain) program A is adopted, 200 people will be saved (from a disease).” B. “If Program C is adopted, 400 people will certainly die.” If we give these sentences a careful examination, we will find out that they have exactly the same meaning. But the way they are presented give people the illusion that C is completely negative while A is positive. This mental tunnel is about how our own languages can lead us to cognitive illusions.

“Not Touching Base Rates” and “The Uncertainty Effect” are also very interesting and commonly found mental tunnels that cause wrong impressions. The former is about making judgment without knowing the background information. Even I can come up with a simple example for it. Person A who has never taken introductory science classes going for an advanced science class just because he/she heard it from person B that the advanced class is easy without knowing that person B has been a science genius since elementary school and has finished all advance science classes by high school. I am sure this type of problems happens to all of us at some point in our life. We can really put ourselves into disastrous situations because of misconception caused by lack of background information. “The Uncertainty Effect” is also a very interesting mental tunnel that we constantly get ourselves into. I can completely relate to the example Piattelli-Palmarini used to explain it. A student is planning to take a trip after an exam. He/she will definitely go on the trip if he has already received the grade from the exam, no matter he passed or failed the exam or not. But the funny part is that when the student is still uncertain of his/her grade because he/she has not received it, he/she will completely loose the drive to plan for the trip. This also happens to me a. When I am being kept up in the air about something, I will lose interest in doing what I have planned to do later.

At the end of Chapter 4,  Piattelli-Palmarini talks about magical thinking. Many people are aware that an object or an idol would not have anything to do with their life, yet they are still willing to believe that these idols or “magical” objects can bring good luck. I can also totally relate to it because it happens to me. My mother is into all those Chinese superstitions and keeps sending me those “magical objects”. Even though I know that my future depends on myself and those objects cannot bring me good luck, I still put them carefully in the positions where my mother instruct me to put them and get nervous when I say something disrespectful about these “magical objects”. I am actually a little nervous as I am writing about it right now! This is clearly a cognitive illusion working on me.

My second most favorite chapter is Chapter 7, which talks about 7 “serious insidious perils that support our illusions of knowing” (115). I find it very funny that Piattelli-Palmarini passionately uses “The Seven Deadly Sins” from the Bible to refer to his seven hazards that support cognitive illusions and make people irrational decisions. But these “7 Deadly Sins” are easily committed. For example, we can be overconfident to pass a biased judgment. People are very scared shark attacks, yet as much scared of driving, even though much more people die from car accidents than from shark attacks each year just because shark attacks are much more widely publicized and described with much more disturbing details. And there are all those movies that picture sharks as big flesh-eating monsters. This illustrates one of the “sins”: “Ease of Representation”(127). Piattelli-Palmarini used Gulf War during Bush administration to demonstrate the “anchoring” sin. The real number of Iraqi civilians killed in the war are much higher than the number reported, yet people still tend to anchor to the reported number. I also find another example from current events. The government-reported unemployment rate is 3% even though the actual unemployment rate is about 30%. Yet most people, including me, are still willing to stick to the reported unemployment rate.

In conclusion, I enjoyed reading this book very much. The circumstances presented in the book can be easily linked to our everyday life. I learned many things about humans’ cognitive weakness from this book. It will sure improve my rational decision making skills. My only issue with this book is that sometimes the author’s writing style is a little hard for me to understand. But I am sure this is just a personal issue. I will still recommend this book to others, who want to see the world better.