Chapter Summary<\/summary>\nThis chapter explores the lie detector as a case study in the history of applied psychology, critically examining how it emerged as a cultural and scientific artefact in the United States during the period prior to the start of the Second World War. Rather than asking whether the polygraph \u2018really works\u2019, the chapter applies the tool for critical thinking of discourse analysis to investigate how the lie detector came to signify truth, objectivity, and guilt. Through an exploration of historical context, key individuals, and the socio-technical development of the polygraph, students are introduced to the ways in which psychological tools are shaped by, and help shape, the discourses of science, justice, and emotion. Focusing on the competing visions of William Moulton Marston and Leonarde Keeler, the chapter uncovers the ideological contradictions embedded in early lie detection discourse, including the tension between mechanical objectivity and human interpretation. It analyses the subject positions (expert, suspect, machine), interpretative repertoires (truth machine versus performance), and ideological dilemmas (science versus spectacle) that structure the polygraph\u2019s authority. The chapter concludes by showing how the lie detector functioned as a technology of power: as a tool of police discipline, therapeutic intimacy, and spectacular cultural performance. Ultimately, the polygraph is revealed to be not merely a machine but a discourse: it was a way of thinking, seeing, and acting that reshaped ideas about truth, guilt, and psychological expertise. By applying discourse analysis, students are invited to question how psychological knowledge is produced, validated, and operation-alised in both science and society.<\/p>\n<\/details>\n<\/div>\n\n\n\n
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Chapter 18 – Quiz<\/h2>\n\n\n\n