The Science of Deception tells a tale of the cultural shift from caveat emptor to the unwary purchaser, via Barnum, illusions, spiritualism, trademarks, lie detectors and personality tests. The title offers two readings, something paralleled in Pettit's approach: this book concerns scientific examination of deception but also how deception was incorporated into scientific methodology. It highlights both the formation of a discipline, replete with quarrels over boundaries, theories and methods, and the development of one of the central features of selfhood.

The term ‘science’ is deliberately deployed, as Pettit examines how psychologists claimed expertise through the scientific nature of their studies of deception and claimed that deception was methodologically crucial in order to glean true scientific knowledge of inherently deceitful human subjects. Yet he also observes the tension between the ideal of ‘transparent’ science and the psychologists' deceptions, interweaving tales of psychologists' escapades with the intense debates over ideals and ethics which took place within the discipline and beyond. Both culturally and within the discipline of psychology, Pettit argues, deception was established as both normal and problematic; to be expected both in the population at large and in the methodology of psychologists, but to be carefully observed and regulated.

Inextricably intertwined with this is the rise of the market economy, where conmen sought to deceive for profit, and even unintentional deception could result in a consumer purchasing an imitation and businesses selling the ‘real deal’ losing out to unscrupulous competition. Pettit shows how psychologists themselves were subject to the taint of money, particularly in light of their problematic incorporation of deceit into their practices. They policed their own ranks for commercialization that might diminish the science's credentials, as Pettit observes in the case of ‘entrepreneurial’ lie detector advocate Leonarde Keeler, one psychologist in the book's colourful cast of characters.

Structured chronologically, each chapter focuses on a particular circumstance of deception and the way in which psychologists attempted to apply their science. Chapter 1 traces the move from antebellum portrayals of innocent victims of conmen to later views of complicit victims, betrayed by their psychological failings of hidden desire and greed. The ‘decade of the illusion’ is the subject of Chapter 2, which traces how the concept of humans possessing limited mental resources produced innovation in the laboratory and in commerce during the Golden Age. This chapter introduces a number of psychologists and draws their battle lines, along which skirmishes recur throughout the rest of the book.

Psychologists' investigations of spiritualists, and the debunking of those who profited from knowing others' minds in order to firmly establish the boundaries of psychology, are the focus of the third chapter. This is followed by a chapter on psychologists' far less successful attempts to establish themselves as experts on the inattentive mind of the unwary purchaser in judicial investigations of trademark infringement. Another chapter on psychology, law and order follows with an examination of the construction of pathological liars and rise of the lie detector. The phrasing of critiques of lie detection in terms of quackery and patent medicine is considered, and Pettit also notes the way in which particulars were rejected but the view of the self as deceitful became generally accepted. Finally, huge-scale investigations of personality and character are scrutinized in relation to cultural concerns of the moral corruption of consumer society.

The narrative traces the various ways in which psychologists sought expertise by making the claim that the unaided judgement of individuals was no longer capable of navigating fraudulent appearances due to an increasingly urban, anonymous, commercial culture. Complexity appears from psychologists' disputes over whether the solution to this was individualism and public consumption of psychological science, or the policing of society using technocratic, certified psychological expertise. Added to this, the communication of science is shown to have been far from straightforward as the media and the public are shown to choose, adapt and discard psychological thought.

Though perhaps a challenge for an undergraduate reader, this work is relevant to those interested in discipline formation and boundary construction, science communication and commercialization, and late nineteenth- and early twentieth-century American academic and intellectual culture, to name a few. The drawback of this book is apparent from the title; it is another account of psychology centred only on America. However, this book is novel in other ways. Psychology is often described as a problematic subject, which can be seen as more an assemblage of fields than a single discipline; Pettit presents not a history of behaviourism or psychoanalysis, but a history that includes both, and more. In taking deception as a category of historical analysis, he is able to present a synthetic picture of psychology which moves beyond constraints such as approach or institution, applied, theoretical or laboratory work.