This chapter describes Edgar Rubin's education in experimental psychology in the laboratory of Alfred Lehmann (1858–1921), the pioneer of experimental psychology in Denmark. Lehmann, a natural scientist, had trained with Wilhelm Wundt in Leipzig and became a pioneer of psychophysiology and an enormously productive researcher. Some major aspects of his research are discussed, such as on the physiological concomitants of psychological states, including the emotions, as well as his criticisms of spiritualism. Lehmann was Edgar Rubin's most important mentor at the University of Copenhagen in the years 1905–1910. Under Lehmann's tutelage, Rubin conducted a study on the perception of warmth leading to his first published scientific paper. During his student years at the University of Copenhagen, Rubin led a discussion group known as Ekliptika that counted among its members the physicist Niels Bohr.