Personal Reflections and Acknowledgments

IN SOME SENSE, this book is George Mandler's fault-surreptitiously sticking ideas in my head without my awareness. He hired me into the nascent Psychology Department of the University of California, San Diego, during the first year of the department's existence: the University itself had not yet graduated any students. Before I knew it, I had written a book (Memory and Attention} for his editorial series; developed an introductory textbook (Human Information Processing, written with Peter Lindsay), because of the course he had Peter and me teach; reconsidered my research on memory; and then entered the field of human error and accidents-whence my interest in design (under the philosophy that most human error is, in actuality, design error).

The Center for Human Information Processing-founded and run by Mandler-was host to the perceptual psychologist J. J. Gibson for a few summers, and these extended stays led to my many debates and

continual disagreements with Gibson. These were delightful disagreements, enjoyed by both of us, disagreements of the most fruitful, scientific kind, the kind that teaches. The combination of my interest in errors and my adaptation of Gibson's notion of affordances led to The Design of Everyday Things. (Had Gibson not died, I'm certain he would still be arguing with me, disagreeing with my interpretation of his concept, ostentatiously disconnecting his hearing aid to show that he wasn't listening to my rebuttals, but secretly smiling and enjoying every minute.)

George was both a cognitive psychologist and a major figure in the study of emotion. But even though I spent many hours debating and discussing topics in emotion with him, reading all his works, I never knew quite how to integrate emotion into my studies of human cognition and, especially, into my studies of the design of products. I even gave a talk at the very first conference on cognitive science, in 1979, entitled "Twelve Issues for Cognitive Science," with emotion as number twelve. But even though I said we should study it, I didn't myself know how to go about doing it. My argument was convincing to at least one person in the audience: Andrew Ortony, now a professor at Northwestern University, tells me that he switched his area of research to emotion as a result of that talk.

In 1993,1 left academia to join industry-serving as vice president at Apple Computer and then as an executive in other high-technology companies, including Hewlett Packard and an online, educational startup. In 1998, my colleague Jakob Nielsen and I established a consulting firm, the Nielsen Norman group, which has exposed me to a wide variety of products in several different industries. Eventually, though, academics drew me back, this time to the computer science department at Northwestern University. I now spend half time at the university, the other half with the Nielsen Norman group.

At Northwestern University, Andrew Ortony reawakened my dormant interest in emotion. In the decade that I was away from academia, much progress had been made in understanding the neuroscience and psychology of emotion. Moreover, while in industry, helping

bring out a wide variety of products, from computers to appliances to web sites, I became sensitive to the powerful emotional impact that designs can produce. People were often far less interested in how well something worked, or even in what it did, than in how it looked and how it made them feel.

Together with William Revelle, a personality theorist in the department of psychology, Ortony and I decided to re-examine the literature on affect, behavior, and cognition to try to understand this emotional attraction. As our work progressed, it became clear that emotion and affect should not be separated from cognition-nor those from behavior, motivation, and personality; all are essential to effective functioning in the world. Our work forms the theoretical background for this book.

At roughly the same period, Bill Gross of Idealab! started a new company-Evolution Robotics-to create robots for the home. He asked me to join their advisory board; before long, I was deeply engrossed in the science of robots. Robots, I soon determined, need to have emotions to survive; indeed, emotions are essential for all autonomous creatures, humans or machine. To my pleasant surprise, I discovered that a research paper I had written in 1986 with the neuropsychologist Tim Shallice, on "will" as a control system, was being used in robotics. Aha! I began to see how it all fit together.

As these separate approaches coalesced, applications dropped out naturally. Our scientific explorations led us to propose that effective processing is best analyzed at three different levels. This insight clarified many issues. It soon became clear that many of the arguments about the role of emotion, beauty, and fun versus marketing concerns, advertising claims, and the positioning of products-along with the difficulties of making a product usable and functional-were often debates across the different levels of processing. All these issues are important, but all have different levels of influence, with different time courses, and at different places in the cycle of purchase and use.

My goal in writing this book is to put these apparently conflicting themes into one coherent framework based upon the three-level theo-

ry of affect, behavior, and cognition. With this framework I aim to provide a deeper understanding of the design process and the emotional impact of products.

So, thank you, George; thank you, Andrew; thank you, Bill.

THIS BOOK, like all my works, owes its existence to many other people. It started with the ever encouraging prods of both my patient agent, Sandy Dijkstra, and my business partner, Jakob Nielsen. No, not quite nagging, but continual reminders and encouragement. I'm always writing, always jotting things down, so out of these notes I created a manuscript entitled "The Future of Everyday Things." But when I tried teaching this material to students at Northwestern University, I discovered it lacked cohesion: the framework that tied the ideas together came from the new work on emotion that I was doing with Andrew Ortony and Bill Revelle, and this was not part of the book.

Ortony, Revelle, and I were developing a theory of emotion, and as we made progress, I realized that the approach could be applied to the field of design. Moreover, the work finally enabled me to resolve the apparent contradictions between my professional interest in making things usable and my personal appreciation of aesthetics. So I discarded that first book manuscript and started anew, this time using the theoretical work on emotion as a framework. Once again, I tried teaching the material, this time with far better success. My students in that first class, and then the ones who tried out the manuscript of this book, were all most helpful in transforming unrelated notes into coherent manuscript.

Along the way, my professional colleagues have provided considerable advice and resources. Danny Bobrow, my long-term colleague, with intelligent pokes, prods, and irritating questions where he would find the flaws in any argument I attempted. Jonathan Grudin, with a continuous flow of email, oftentimes from dawn to dusk, with comments, papers, and critiques. Patrick Whitney, head of the Institute of Design in Chicago, who invited me to serve on his board and provided

both insightful comments and access to the industrial design community. Many of the faculty of the Institute of Design have been most helpful: Chris Conley, John Heskett, Mark Rettig, and Kei Sato. Nirmal Sethia, from California State Polytechnic University, Pomona, has been a continual source of contacts and information: Nirmal seems to know everyone in the field of industrial design and has made sure I was up-to-date.

THE POWERFUL team of interaction designers Shelley Evenson and John Rheinfrank always provide great insights (and John is a great chef). I thank Paul Bradley, David Kelly, and Craig Sampson of IDEO and Walter Herbst and John Hartman from Herbst LaZar Bell.

Cynthia Breazeal and Roz Picard from the MIT Media Laboratory provided numerous useful interactions, including visits to their laboratories, which contributed considerably to chapters 6 and 7. Rodney Brooks, head of the Artificial Intelligence Laboratory at MIT and a roboticist, was also a great source of information. Marvin Minsky, as always, provided much inspiration, especially with the manuscript of his forthcoming book, The Emotion Machine.

I tested many of my ideas on the several bulletin boards of the CHI community (the international society for Computer-Human Interaction), and many respondents have been most helpful. The list of correspondents is huge-hundreds-but I am especially indebted to my fruitful conversations with and suggestions from Joshua Barr, Gilbert Cockton, Marc Hassenzahl, Challis Hodge, William Hudson, Kristiina Karvonen, Jonas Lowgren, Hugh McLoone, George Olsen, Kees Overbeeke, Etienne Pelaprat, Gerard Torenvliet, and Christina Wodtke. I thank Kara Pernice Coyne, Susan Farrell, Shuli Gilutz, Luice Hwang, Jakob Nielsen, and Amy Stover of the Nielsen Norman group for their lively discussions.

Jim Stewart from Microsoft's XBOX division provided discussions of the game industry and the XBOX poster for my walls ("Go outside. Get some air. Watch a sunset. Boy, does that get old fast.").

The book slowly transformed from eighteen disorganized chapters into the present seven chapters, plus prologue and epilogue, through two massive rewrites, guided by Jo Ann Miller, my editor at Basic Books. She worked me hard-fortunately for you. Thanks, Jo Ann. And thanks to Randall Pink for diligently gathering final photographs and permissions.

Although I have left out many who helped during the long gestation period for this book, my thanks to all, named and unnamed, including all my students at both Northwestern University and the Institute of Design who helped me clarify my thoughts through the various revisions.

Don Norman Northbrook, Illinois