Our literary agent, Jim Levine, was instrumental in helping us craft a proposal for our book that brought all of the everyday illusions together into a coherent narrative. He also deserves the credit for coining the phrase “everyday illusions.” Our thanks also go to Dan Ariely for introducing us to Jim. Steven Pinker and Daniel Gilbert graciously helped with our proposal. Elizabeth Fisher at Levine-Greenberg was tremendously helpful in coordinating international-rights sales and in guiding us through the complicated process of negotiations with international agents and publishers.
We could not have completed this project without the flexibility and support provided by our academic institutions, the psychology departments at Union College (Chris) and the University of Illinois (Dan). Dan would also like to acknowledge the Center for Advanced Study at the University of Illinois for sabbatical support when we were beginning our research for the book.
Since we have tried to explain everyday illusions by appealing to scientific research, our success depends on the work of many other scientists. Although we describe much of our own research in this book, that research did not occur in a vacuum, and we were not alone in doing it. We would like to thank all of our research collaborators and coauthors, without whom much of that work could not have been done. More broadly, we would like to thank all of our colleagues whose work we cited and discussed throughout this book, mostly without their knowledge. Although they might not always agree with our interpretations of their ideas and results, we hope that we have done justice to their important scientific contributions. Chris would like to acknowledge the lifelong influence of Stephen Kosslyn, his mentor before, during, and after graduate school, who taught him much about scientific thinking and generously supported him in the pursuit of his own independent research directions. Dan would particularly like to thank his long-term collaborator, Daniel Levin, whose ideas and writing about metacognition helped motivate many of the arguments we put forward throughout this book.
Finally, we would each like to thank our families. Chris thanks his wife, Michelle Meyer; their son, Caleb; and his own parents, Daniel and Lois Chabris, for all their love and support, and for putting up with him and the whole project. Dan thanks his wife, Kathy Richards, and their children, Jordan and Ella, for tolerating far too many long days and working weekends. He would also like to thank his parents, Pat and Paul Simons, and his brother, David Simons, for helping him to think clearly and for arguing with him when he didn’t.
We hope that we haven’t overlooked anyone whom we should have thanked, but if we have, please consider attributing our omission to an everyday illusion rather than an intentional slight.
NOTES
Chapter 1: “I Think I Would Have Seen That”
1. Details of this case are drawn from a variety of sources, including several excellent, in-depth investigative articles written by award-winning journalist Dick Lehr for the Boston Globe. Lehr has written a book, The Fence (New York: HarperCollins, 2009), that discusses the case and the larger issues surrounding it. Our sources also include the following articles by Dick Lehr in the Globe: “Boston Police Turn on One of Their Own,” December 8, 1997, p. A1; “Truth or Consequences,” September 23, 2001; “Free and Clear,” January 22, 2006; “Witness in ’95 Brutality Case Offers New Account,” September 17, 2006. Other sources included the opinions of the U.S. district and circuit courts in the case, especially United States v. Kenneth M. Conley, 186 F.3d 7 (1st Cir. 1999); and Kenneth M. Conley v. United States, 415 F.3d 183 (1st Cir. 2005); as well as a brief filed by Conley in U.S. District Court for the District of Massachusetts (Kenneth M. Conley v. United States, No. 01-10853-WGY, No. 01-97-cr-10213-WGY, June 26, 2003). When any sources provided discrepant details, we have regarded The Fence as definitive because it was written most recently and incorporated the most research.
2. Biographical information about Michael Cox is from a profile prepared for his participation in a conference on “Race, Police, and the Community” at Harvard Law School, December 7–9, 2000, law.harvard.edu/academics/clinical/cji/rpcconf/coxm.htm (accessed May 18, 2009).
3. S. Murphy, “A Settlement Is Reached in Beating of Police Officer,” The Boston Globe, March 4, 2006, p. B3.
4. Lehr, “Boston Police Turn on One of Their Own.”
5. The juror quotes are from Lehr, “Truth or Consequences.” The widespread belief that police officers are superior to civilians at observing and remembering relevant information appears to be inconsistent with the scientific evidence; e.g., P. B. Ainsworth, “Incident Perception by British Police Officers,” Law and Human Behavior 5 (1981): 231–236.
6. Perjury is the crime of making a false statement while under oath in a legal proceeding. Each individual false statement can lead to a separate charge of perjury. Conley was accused of perjuring himself by claiming (1) that he did not see Cox (or any other police officer) chase Brown to the fence, and (2) that he did not see the attack on Cox. He was acquitted of the second charge but convicted of the first. His conviction for obstruction of justice, which is the more general crime of interfering with law enforcement, in essence flowed automatically from the jury’s finding that he had committed perjury, and it did not reflect any additional malfeasance.
7. All four suspects from the gold Lexus were arrested that night. The victim at the hamburger restaurant had been shot multiple times in the chest, allegedly because he’d witnessed another shooting at a nearby bar earlier that same night. He died several days later. The next year, two of the suspects were convicted of first-degree murder; Smut Brown, who wasn’t accused of pulling the trigger himself, was acquitted. Michael Cox eventually recovered from his physical injuries and returned to work after a six-month absence. He went on to become a deputy superintendent of police in Boston. Two of those accused by Cox of being involved in the beating were later found civilly liable and lost their jobs when Cox sued the Boston Police Department.
8. Our study was reported in the following article: D. J. Simons and C. F. Chabris, “Gorillas in Our Midst: Sustained Inattentional Blindness for Dynamic Events,” Perception 28 (1999): 1059–1074. Dan first learned about Neisser’s 1970s experiments when he was a college student. Neisser’s experiments used a complicated mirror apparatus to create ghostlike images of people who appeared to walk through one another. He designed those videos to test whether subjects could pay attention to one set of people while ignoring others who occupied exactly the same areas. That is, he asked whether people focus their visual attention on individual objects rather than on individual regions of space, and when they focus on objects, how selectively they focus. The most detailed description of Neisser’s earlier studies that inspired our experiment is in U. Neisser, “The Control of Information Pickup in Selective Looking,” in Perception and Its Development: A Tribute to Eleanor J. Gibson, ed. A. D. Pick, 201–219 (Hillsdale, NJ: Erlbaum, 1979).
9. The term inattentional blindness comes from the title of a 1998 MIT Press book by Arien Mack of the New School for Social Research in New York and the late Irvin Rock of the University of California at Berkeley, two psychologists who did pioneering work in this area. In their original experiments, subjects stared at a point on a computer screen until a large cross appeared. One arm of the cross—either the horizontal or the vertical—was always longer than the other, and subjects tried to judge which was longer. The cross was visible for only a fraction of a second before it disappeared, so this was not an easy judgment to make accurately. After a few trials of this task, an additional, unexpected object appeared along with the cross. The object could be a geometric figure like a small square, or a simple picture, or even a word. In most cases about one-quarter of subjects claimed not to have seen the unexpected object. Neisser’s original selective-looking studies and our gorilla experiment provide a somewhat more dramatic demonstration of inattentional blindness because they presented a large, central, moving object for several seconds, rather than a briefly flashed static image, but the conclusion is consistent: It is surprisin
gly easy to not notice what is in plain view.
10. We hired SurveyUSA to ask a nationally representative sample of fifteen hundred adults a series of questions designed to probe how people think about the workings of their own minds. The respondents matched the entire U.S. population in gender, age, and regional distribution. SurveyUSA used a prerecorded voice to read a set of sixteen statements, and after each one, respondents used their telephone keypad to indicate whether they strongly agreed, mostly agreed, mostly disagreed, strongly disagreed, or weren’t sure. We also collected demographic information about each person’s age, sex, income level, and race. Finally, we asked people how many psychology classes they had taken and how many books about psychology they had read over the past three years. This sort of prerecorded survey provides a level of control that is ideal for scientific research because each person hears exactly the same questions, in the same order, and in the same voice. SurveyUSA has been one of the most accurate political polling firms over the past few election cycles. The entire poll was completed over the course of one week in early June 2009. The percentages of agreement we give represent the sum of respondents who answered “strongly agree” or “mostly agree” to the question. If 75 percent either strongly or mostly agree with a statement, this means that the other 25 percent either strongly or mostly disagree, or are not sure. However, it is important to keep in mind that all of the statements we presented are almost certainly false, so the rate of agreement in a world without everyday illusions should be close to 0 percent!
11. Our colleague Daniel Levin, a psychology professor at Vanderbilt University, along with Bonnie Angelone of Rowan University, described the gorilla experiment to over one hundred undergraduate students, but without actually showing them the video or asking them to perform the task. After hearing about the experiment, including the appearance of the gorilla—but not hearing about the results—they were asked whether they would have noticed the gorilla if they had participated in the experiment themselves. Fully 90 percent of them predicted that they would have seen it. When we originally conducted the study, though, only 50 percent actually did. See D. T. Levin and B. L. Angelone, “The Visual Metacognition Questionnaire: A Measure of Intuitions About Vision,” American Journal of Psychology 121 (2008): 451–472.
12. Simons and Chabris, “Gorillas in Our Midst.”
13. CSI: Crime Scene Investigation, Season 2, Episode 9, “And Then There Were None” (originally broadcast on CBS, November 22, 2001).
14. Lehr, The Fence, 270.
15. O. Johnson, “Fed Court: Convicted Hub Cop’s Trial Unfair,” The Boston Herald, July 21, 2005, p. 28. Ironically, the witness, Officer Robert Walker, had initially claimed that he saw Conley at the fence. Later he recanted, saying that he had not actually seen Conley but said that he had because he was at the scene and should have seen him. Another victim of the illusion of attention! The appeals court found that the problem was not Walker’s faulty intuition about how the mind works, but the fact that the defense was never told about an FBI memo that documented his later requests for hypnosis and a polygraph (lie detector) test, information that would tend to cast further doubt on the credibility of his memories.
One more interesting twist in the case of Kenny Conley deserves mention. In 2006, months after Conley rejoined the police force, Smut Brown was interviewed by Dick Lehr while Brown was in jail in Maine for a drug conviction (“Witness in ’95 Brutality Case Offers New Account”). Brown told Lehr about a crucial misrepresentation in the original trial eight years earlier. Brown had testified that he had seen a white cop on the other side of the fence, and he identified Conley as the white cop who had eventually caught him. The way this information was presented in court gave the impression that Conley was the white cop Brown had seen standing next to the beating. But Brown did not specifically identify Conley as the cop he had seen next to the beating. The prosecution never asked him to, and the defense did not cross-examine him on this specific point. Brown later said that he had gotten a good look at the officer on the other side of the fence, but not at the one who caught him, and he had just assumed they were the same person. Speaking of Conley, Brown told Lehr, “When I seen him sitting at the defense table I didn’t have no clue, like, why they were using me for that—because I didn’t recognize him.” In fact, Brown claimed that just before he testified, he spotted the cop he had seen at the site of the beating standing in the courthouse hallway and that he told this to the FBI agent in charge of the case. If true, Brown’s jailhouse claim would further undermine the legal case against Conley, by subtracting one witness who placed him at the scene of the attack on Cox. But as we will discuss in Chapter 2 of this book, this sort of sudden recollection is easily distorted, and trusting a memory like this can be dangerous, even when the person doing the remembering does not have self-serving motives for changing his previous story.
16. C. Ross, “2 Embattled Cops Welcomed Back to Force,” The Boston Herald, May 20, 2006, p. 6; Lehr, “Free and Clear.”
17. D. Wedge, “Two Officers Cleared in ’95 Beating Get Back $$$,” The Boston Herald, November 20, 2007, p. 4.
18. Lehr, The Fence, 328.
19. This quote is from p. 100 of R. Pirsig, Zen and the Art of Motorcycle Maintenance (New York: William Morrow, 1974).
20. Except as noted, all of the quotes and facts about this incident are drawn from the wonderfully detailed and illustrated National Transportation Safety Board (NTSB) Marine Accident Brief for Accident # DCA-01-MM-022 (www.ntsb.gov/publictn/2005/MAB0501.htm). Other sources include M. Thompson, “Driving Blind,” Time, February 18, 2001 (www.time.com/time/magazine/article/0,9171,99833,00.html); T. McCarthy and J. McCabe, “Bitter Passage,” Time, April 15, 2001 (www.time.com/time/magazine/article/0,9171,106402-1,00.html); and S. Waddle, The Right Thing (Nashville, TN: Integrity Publishers, 2003).
21. This quote is used by permission from the transcript of a portion of an interview of Scott Waddle by Stone Phillips for Dateline NBC.
22. For a recent analysis of “looked but failed to see” accidents, see A. Koustanaï, E. Boloix, P. Van Elslande, and C. Bastien, “Statistical Analysis of ‘Looked-But-Failed-to-See’ Accidents: Highlighting the Involvement of Two Distinct Mechanisms,” Accident Analysis and Prevention 40 (2008): 461–469.
23. D. Memmert, “The Effects of Eye Movements, Age, and Expertise on Inattentional Blindness,” Consciousness and Cognition 15 (2006): 620–627. Memmert’s subjects were children with an average age of about eight years, but the rate of noticing the gorilla was virtually the same as in our studies of college students: 8 out of 20, or 40 percent. Psychologists use many different devices for tracking a subject’s eye movements. A typical design involves a small, lightweight helmet with one or two cameras directed at the subject’s eyes. Harmless infrared light is bounced off the subject’s eyes and detected by the cameras. Because the cameras are in a fixed position relative to the subject’s head (they’re attached firmly to the helmet, which is attached firmly to their head), experimenters can use these reflections to determine which way subjects are looking. Many systems use a second camera to determine where the subject’s head is relative to the scene being viewed, providing the necessary additional information to calculate exactly where in an image the subject is fixating their eyes. Current eye-tracking systems can measure the focus of gaze with exceptionally high spatial and temporal precision.
24. Details about this accident and its consequences were reported in an article on ESPN.com entitled “Big Ben in Serious Condition After Motorcycle Accident” on June 12 and June 13, 2006 (sports.espn.go.com/nfl/news/story?id=2480830). Other details and some quotes come from the following stories: M. A. Fuoco, “Multiple Injuries, Few Answers for Roethlisberger,” The Pittsburgh Post Gazette, June 13, 2006 (www.post-gazette.com/pg/06164/697828-66.stm); J. Silver, “Roethlisberger, Car Driver Are Both Charged,” The Pittsburgh Post Gazette, June 20, 2006 (www.post-gazette.com/pg/06171/699570-66.stm); D. Hench, “Steelers’ QB Hurt in Crash,” Po
rtland Press Herald, June 13, 2006.
25. Statistics and quotes are drawn from the Hurt report: H. H. Hurt Jr., J. V. Ouellet, and D. R. Thom, Motorcycle Accident Cause Factors and Identification of Countermeasures, Volume 1: Technical report. Traffic Safety Center, University of Southern California, 1981.
26. Hurt et al., Motorcycle Accident Cause Factors, 46. The larger study discussed in this report conducted on-site accident evaluations for 900 motorcycle accidents in the Los Angeles area, and it also examined 3,600 accident reports. The criteria used to select these 62 cases for additional analysis were not described in the report.
27. S. B. Most, D. J. Simons, B. J. Scholl, R. Jimenez, E. Clifford, and C. F. Chabris, “How Not to Be Seen: The Contribution of Similarity and Selective Ignoring to Sustained Inattentional Blindness,” Psychological Science 12 (2000): 9–17.
28. P. L. Jacobsen, “Safety in Numbers: More Walkers and Bicyclists, Safer Walking and Bicycling,” Injury Prevention 9 (2003): 205–209. These results have been corroborated in other countries and other time periods; for similar analyses in Australia, see D. L. Robinson, “Safety in Numbers in Australia: More Walkers and Bicyclists, Safer Walking and Bicycling,” Health Promotion Journal of Australia 16, no. 1 (2005): 47–51. See also Tom Vanderbilt’s excellent book Traffic (New York: Knopf, 2008), which discusses this issue and a number of related issues involving expectations and accidents. This book was an informative resource for the material in this chapter on driving.
The Invisible Gorilla: And Other Ways Our Intuitions Deceive Us Page 29