presentism, and rationalization. In describing realism, Gilbert summarizes recent research on memory and perception to show that the brain, in constructing memories, tends to fill in details that may or may not have been at the scene, while not paying any attention to details missing from the initial picture or view. Realism is a subjective process in that what is perceived and remembered is what the mind wants to see and remember. The end result is a false recollection or skewed picture, lacking in details. Presentism describes the overriding mental tendency to remember the past or predict the future based on present events, circumstances, and feelings. Rationalization is the tendency to view events differently after they have occurred, with a positive spin.

Feelings of regret at not having done things differently is also a compounding factor, as one tends to make choices, such as getting married or having children, that one anticipates will eliminate, or at least minimize, future regret. Interestingly enough, the human tendency is to regret what one did not do much more than regretting what one actually didanother trick of perception and memory in order to put a positive spin on remembered reality. The same holds true for bad experiences. If one experiences something that is awful or painful and impossible to change, one instead focuses on changing one’s perception. This is largely an unconscious process that alters a person’s ability to predict accurately how happy he or she will feel after an event. Actual perception is a balanced combination of the facts woven with bits of one’s own imagination and thoughts to create a believable “reality.” Gilbert describes this balance as a “psychological immune system” that works to maintain mental health.

Gilbert concludes by describing how to make better predictions about future happiness. He notes that people have both firsthand and secondhand knowledge at their disposal. The inability to remember something with photographic perfection causes people to recall their firsthand knowledge imperfectly. In considering such unconscious self-deception, Gilbert theorizes that people do not know themselves very well at all. Because memories are selective, and perhaps sprinkled with what one thought or imagined had happened, hindsight forces one to feel differently than one would have initially predicted, making it even more difficult accurately to predict how one would feel if, for example, she got left at the alter. Because people do not accurately remember how they felt the previous time, they are prone to repeat behavior that did not bring pleasure. As a result, people are unable to learn from their experiences in a way that would help them make predictions about future happiness.

Gilbert notes that because of false memories and a mental tendency to see the present first, the best way to make predictions about future happiness is to examine the feelings of those who are currently experiencing what one anticipates in one’s own future. Research demonstrates that using secondhand knowledge to estimate future emotional states tends to result in more accurate predictions than relying on personal experiences and interpretations.

Gilbert notes that the best and easiest way to determine how one will feel about one’s choices is to ask someone else who is currently experiencing what one is contemplating doing. Instead of a crystal ball, the greatest forecasting tool would therefore be a compilation of experiences that one could peruse when contemplating one’s future. Those who want to know if they would like being married or having children could look up the accounts of people who had done those things, in order to make a more accurate prediction about how one who is considering doing that thing would feel when he or she does it. Unfortunately, as Gilbert points out, people have a tendency to see themselves as unique compared to others and therefore make the assumption that their experiences are dissimilar. This makes it difficult to apply the experiences of others to one’s own circumstances.

Gilbert’s writing is continually reinforced with studies of human behavior, including many of his own studies on human forecasting and predictions. Stumbling on Happiness is not intended as a popular psychology self-help book to help people live happier lives. Gilbert’s intention is to provide a text that explains the mental phenomenon of constructing imagined futures and predicting how one will feel after one “gets there.” By explaining the process and describing the phenomenon, Gilbert offers some hope of overcoming imagination in order to make better predictions about choices and thus fostering future happiness. The information presented is complex at times, but Gilbert has done an outstanding job conveying it in lay terms with an organizational style that facilitates comprehension with an added touch of humor. Relevant theories from other disciplines are included to help explain statistics and views of perception and time. Illustrations are provided for clarity. A somewhat amusing feature is the inclusion in some chapters of so-called brain teasers to illustrate the susceptibility to mental or optical illusions. This textual illustration feature is particularly relevant because it is easy to read through the text and, as Gilbert predicts, think to oneself that “I would never do what he is saying I would.” The exercises allow the reader to see that he or she may indeed be just as susceptible to optical and memory illusions as everyone else.

Human emotions and experiences, as well as recollections about them, are highly subjective, making them difficult to study. Because of this subjectivity, Gilbert notes that it is difficult to develop an accurate tool of measurement. In order to provide reliable and valid measures in the study of happiness, Gilbert explains the need to accept three tenets: First, ambiguity will be present. Second, self-reports are the least flawed of all possible measures. Third, with statistics, it is possible to draw conclusions about human behavior when large population samples repeatedly show the same results. By asking the same questions of enough populations, inferences can be made from consistent responses.

A potential disadvantage to Gilbert’s research and theories about happiness lies in the very statistics he uses. A quick examination of his sources reveals the primary populations studied to be students from large research institutions. Students from the University of Texas, Austin, the University of Virginia, and even Harvard University were studied in many of the cases he cites. While some of the other research Gilbert discusses has examined noncollege student populationssuch as children, teens, cancer patients, and lottery winnersadditional research he consults focuses on student populations. It could be inferred, then, that Gilbert’s ideas about human choices are more applicable to populations composed of American college students than to society as a whole. Other researchers are beginning to broaden Gilbert’s studies by examining other groups to see if there is a cross>correlation. So far, it appears that people with a Western European background make predications about future happiness as Gilbert predicted, while East Asian populations show similarities but also some intriguing differences in how they make future predictions of happiness. Overall, the results show the same level of happiness after the fact.

Reviews of Stumbling on Happiness were mixed but overall favorable. At least two reviews questioned Gilbert’s work. A New Republic article by Harvey Mansfield contained an extensive article that questioned Gilbert’s stance on happiness. A review in Library Journal questioned some of the experiments, research findings, and theories used by Gilbert. While the research and theories supplied by Gilbert offer guidance in overcoming personal fallacies, there are also implications in his findings that extend to parenting, counseling, medicine, and business practices. Stumbling on Happiness may be a groundbreaking work on forecasting behavior. The test will be to see how Gilbert’s theories hold when applied to more diverse and stratified populations.