Abstract
This article analyzes how industrial psychologists used mechanical devices to study the efficiency of human labor. One major proponent of this research field, commonly known as "Psychotechnik," was Walther Moede. He invented a so-called bimanual tester-"Zweihandprüfer"-that enabled him to quantify the subjects' performance in aptitude tests, and then translate these findings into forecasts of future efficiency and productivity. Industrial psychologists interpreted their results as seemingly objective and unbiased indicators of the subjects' skills which made it possible to allocate workers, employees, and apprentices to their appropriate position within companies. This article, in contrast, argues that the classification of workers and employees was to a certain degree based on the examiners' qualitative value judgements. Drawing on printed sources such as psychotechnical journals and textbooks as well as experiments of their own with a bimanual tester, the author is able to show how industrial psychologists interpreted, evaluated, and categorized the participants' aptitude test results. Psychotechnicians claimed scientific authority and, hence, the power to classify individuals as "failures" or "gifted." While industrial psychologists argue that they were able to rationalize the distribution of work in the 1920s, this article reveals the leeway there is for interpretation when translating allegedly "objective" test results.