The Invisible Gorilla: And Other Ways Our Intuition Deceives Us. Christopher Chabris

       INTRODUCTION everyday illusions

       “There are three things extremely hard: steel, a diamond, and to know one’s self.”

      —Benjamin Franklin, Poor Richard’s Almanack (1750)

      ABOUT TWELVE YEARS AGO, we conducted a simple experiment with the students in a psychology course we were teaching at Harvard University. To our surprise, it has become one of the best-known experiments in psychology. It appears in textbooks and is taught in introductory psychology courses throughout the world. It has been featured in magazines such as Newsweek and The New Yorker and on television programs, including Dateline NBC. It has even been exhibited in the Exploratorium in San Francisco and in other museums. The experiment is popular because it reveals, in a humorous way, something unexpected and deep about how we see our world—and about what we don’t see.

      You’ll read about our experiment in the first chapter of this book. As we’ve thought about it over the years, we’ve realized that it illustrates a broader principle about how the mind works. We all believe that we are capable of seeing what’s in front of us, of accurately remembering important events from our past, of understanding the limits of our knowledge, of properly determining cause and effect. But these intuitive beliefs are often mistaken ones that mask critically important limitations on our cognitive abilities.

      We must be reminded not to judge a book by its cover because we take outward appearances to be accurate advertisements of inner, unseen qualities. We need to be told that a penny saved is a penny earned because we think about cash coming in differently from money we already have. Aphorisms like these exist largely to help us avoid the mistakes that intuition can cause. Likewise, Benjamin Franklin’s observation about extremely hard things suggests that we should question the intuitive belief that we understand ourselves well. As we go through life, we act as though we know how our minds work and why we behave the way we do. It is surprising how often we really have no clue.

      The Invisible Gorilla is a book about six everyday illusions that profoundly influence our lives: the illusions of attention, memory, confidence, knowledge, cause, and potential. These are distorted beliefs we hold about our minds that are not just wrong, but wrong in dangerous ways. We will explore when and why these illusions affect us, the consequences they have for human affairs, and how we can overcome or minimize their impact.

      We use the word “illusions” as a deliberate analogy to visual illusions like M. C. Escher’s famous never-ending staircase: Even after you realize that something about the picture as a whole is not right, you still can’t stop yourself from seeing each individual segment as a proper staircase. Everyday illusions are similarly persistent: Even after we know how our beliefs and intuitions are flawed, they remain stubbornly resistant to change. We call them everyday illusions because they affect our behavior literally every day. Every time we talk on a cell phone while driving, believing we’re still paying enough attention to the road, we’ve been affected by one of these illusions. Every time we assume that someone who misremembers their past must be lying, we’ve succumbed to an illusion. Every time we pick a leader for a team because that person expresses the most confidence, we’ve been influenced by an illusion. Every time we start a new project convinced that we know how long it will take to complete, we are under an illusion. Indeed, virtually no realm of human behavior is untouched by everyday illusions.

      As professors who design and run psychology experiments for a living, we’ve found that the more we study the nature of the mind, the more we see the impact of these illusions in our own lives. You can develop the same sort of x-ray vision into the workings of your own mind. When you finish this book, you will be able to glimpse the man behind the curtain and some of the tiny gears and pulleys that govern your thoughts and beliefs. Once you know about everyday illusions, you will view the world differently and think about it more clearly. You will see how illusions affect your own thoughts and actions, as well as the behavior of everyone around you. And you will recognize when journalists, managers, advertisers, and politicians—intentionally or accidentally—take advantage of illusions in an attempt to obfuscate or persuade. Understanding everyday illusions will lead you to recalibrate the way you approach your life to account for the limitations—and the true strengths—of your mind. You might even come up with ways to exploit these insights for fun and profit. Ultimately, seeing through the veils that distort how we perceive ourselves and the world will connect you—for perhaps the first time—with reality.