XI.1 January + February 2004
Page: 65
Digital Citation


James Kalbach

back to top  Persuasive Technology: Using Computers to Change What We Think and Do

B.J. Fogg
Morgan Kaufmann, San Francisco, 2003
ISBN 1-55860-643-2 $34.95

Reviewed by James Kalbach

In his new book, Persuasive Technology, B.J. Fogg has formalized a significant, emerging discipline. This discipline is captology, the study of how computers change people's attitudes and behavior. Although it draws from a variety of disciplines, captology is primarily concerned with human-computer interaction (HCI). This element of interaction stands out as a key difference between persuasion in computing technology and persuasion in other media. Captology has tremendous implications on the HCI community.

In the first half of the book, Fogg uses a textbook-like style to distill captology into exhaustive and detailed principles that together form a robust theoretical structure. This structure consists of the functional triad, the three roles that persuasive technologies can play:

1. As tools, persuasive technologies change attitudes or behavior by facilitating a desired outcome. Wearable heart-rate monitors, for instance, help people to adjust their physical behavior to keep their heart rates within a target range.

2. As sensory media, computers can simulate experiences. For example, a program can show cause-and-effect relationships between variables such as population growth and traffic congestion. City planners can then explore options without waiting for real-world consequences and make a more informed decision.

3. As social actors, computers persuade by eliciting social responses. This is based on the observation that people sometimes respond to computers as if they were alive. A simple example is a dialog box offering praise ("Good job!"), which could encourage users to continue.

Later chapters focus on credibility—the perceived believability of technology. Fogg proposes that credibility has two dimensions: trustworthiness and expertise. The most credible products rank highly on both dimensions. Fogg's detailed reports on his Web credibility studies—the topic of his ongoing research at Stanford University (see—are a highlight of this book. Although Fogg's arguments on this topic sound familiar, and even though he may seem to just state the obvious, this is not actually the case. The concept of persuasive technology is like a riddle: The answer is apparent only after it is revealed.

Fogg's discussion of captology goes beyond desktop computers and Web sites. He also covers the roles of mobility and connectivity and then explores the future of captology to identify trends that will guide subsequent research. This discussion is useful but unfortunately does not cover the potential role of emotions in design, a current topic. Also absent is a discussion of how intercultural differences might affect the results he has presented.

In the final chapter of the book, Fogg addresses the ethics of persuasion. This chapter is an important clarification: Although to many of us, persuasion has negative connotations, persuasion is not necessarily a negative concept. In fact, the ancient Greeks believed persuasion to be a cornerstone of democracy. Rather, it is the abuse of persuasion that is negative; for this reason, Fogg excludes coercion and deception from his definition of persuasion and its role in technology. Although the topic remains unresolved, the author also wisely confronts the moral issues behind persuasion and advocates responsibility.

To support his arguments, Fogg successfully pulls together a wide range of research and literature. He also presents a wealth of real-life examples, which helps to make the text quite accessible as a whole. While it is not a how-to book, and does not aim to offer concrete guidelines, Persuasive Technology has a practical feel. Clear, succinct, and devoid of academic density, Fogg's exposition of this broad and complex subject is brilliantly simple. This is the charm and power of the book.

Persuasion in technology happens. Understanding this phenomenon is of primary concern to HCI professionals. Although you may not be sure how to apply what is learned, be sure to read this landmark book. Intuitive, though provoking, and at times mesmerizing, Persuasive Technology may change your view of your own work and of technology as whole.

back to top  New & Upcoming Titles

bullet.gif Advanced Topics in End User Computing

Mo Adam Mahmood, Editor
Idea Group Publishing, 2004
ISBN 1591402972 $64.95

bullet.gif E-Education Applications: Human Factors and Innovative Approaches

Claude Ghaoui, Editor
AAA, 2004
ISBN: 1591402921 $59.95

bullet.gif Emotional Design: Why We Love (Or Hate) Everyday Things

Don Norman
Basic Books, 2003
ISBN: 0465051359 $26.00

bullet.gif Managing Psychological Factors in Information Systems Work: An Orientation to Emotional Intelligence

Eugene Kaluzniacky
AAA, 2004
ISBN: 1591401984

bullet.gif The Social and Cognitive Impacts of E-Commerce on Modern Organizations

Mehdi Khosrow-Pour, Editor
Idea Group Publishing, 2004
ISBN 1591402743 $59.95

bullet.gif Voice User Interface Design

Michael H. Cohen, James P. Giangola, Jennifer Balogh
Prentice Hall, 2004
ISBN 0321185765 $54.99

bullet.gif Windows and Mirrors: Interaction Design, Digital Art, and the Myth of Transparency

Jay David Bolter and Diane Gromala
MIT Press, 2003
ISBN 0262025450 $29.95

back to top  Author

To submit a book review, please email Gerard Torenvliet at

About the Author

James Kalbach is a Human Factors Engineer with LexisNexis. In addition to a masters of library science, he also has a degree in music theory and composition. A list of his compositions can be found here:

back to top 

©2004 ACM  1072-5220/04/0100  $5.00

Permission to make digital or hard copies of all or part of this work for personal or classroom use is granted without fee provided that copies are not made or distributed for profit or commercial advantage and that copies bear this notice and the full citation on the first page. To copy otherwise, to republish, to post on servers or to redistribute to lists, requires prior specific permission and/or a fee.

The Digital Library is published by the Association for Computing Machinery. Copyright © 2004 ACM, Inc.

Post Comment

No Comments Found