The term “Stepchildren of Science” was coined by the experimental psychologist Wilhelm Wundt who used it to describe the marginal areas of the mind sciences that dealt with paranormal phenomena and lacked a rigorous experimental approach. Wundt, along with other critics of occult practices and sciences, spent considerable energy to distance his laboratory-based science from the knowledge claims by parapsychologists who set out to describe and analyze paranormal phenomena such as somnambulism, telekinesis, and telepathy. Heather Wolffram's book is not a cultural history of occultism or the occult sciences per se—areas that have been explored in greater depth by Corinna Treitel in her book A Science for the Soul (2004). Her book is about competing claims for expertise and authority between different groups of scientists and lay people who tried to account for paranormal phenomena in late-nineteenth- and early-twentieth-century Germany. In conceptualizing her work, she relies mostly on Thomas Gieryn's notion of “boundary work” through which existing and emerging fields of inquiry defend their claims of expertise and cultural authority. According to Gieryn, boundaries between scientific disciplines as well as boundaries between scientific disciplines and lay practices are not only defined by specific differences in scientific and cultural practices, but they must also be continuously maintained, enlarged, and policed against encroachments from other scientific disciplines as well as lay practices. In the quest for “epistemic authority,” boundary work aims at either expanding a discipline's knowledge claims or restricting or discrediting the claims by outside groups. As Wolffram shows, in the case of the paranormal sciences, boundary work was a complex game in which occultists (who sought communion with or access to occult forces beyond the natural world) faced the inquiries of parapsychologists such as Albert von Schrenck-Notzing who tried to devise a methodology for the scientific examination of paranormal phenomena. Schrenck-Notzing in turn came under attack from so-called “critical occultists”—critics of occult practices who tried to explain such phenomena in terms of sensory errors, deception, and fraud.

Wolffram mostly focuses on the years of the Empire and the Weimar Republic. Despite the subtitle that promises to take the story to the year 1939, the Nazi period finds only cursory treatment in this book. Still, this is an important contribution to the history of the German mind and life sciences in that it contributes to a deeper understanding of the cultural and professional context in which expert authority is created, accepted, defended, and challenged. Around 1900, psychology was not a securely established academic field with clearly defined areas of professional practice. In addition, amateur occultists, faith healers, and parapsychologists who resorted to hypnosis and suggestion and marketed themselves as healing professionals operated in a context that aroused the suspicions of the regular medical profession, which already felt under attack by natural therapists and other irregular healing practitioners. Some medical experts on the paranormal such as Schrenck-Notzing and the psychiatrist Albert Moll denounced the use of hypnosis by lay practitioners without proper medical training. While they considered hypnosis and suggestion valuable tools for therapy and research, they claimed that in the hands of quacks, the same techniques would pose a danger for the physical, psychological, and moral health of the public.

The academic researchers on occult phenomena, however, did not present a united front. Schrenck-Notzing in particular came under attack by people such as Moll, who accused him of lending credibility to dubious public displays by spirit mediums. The independently wealthy Schrenck-Notzing invited important public figures and luminaries such as Thomas Mann into his private Munich laboratory where they could witness paranormal phenomena such as “ectoplasmic” materializations of human forms emanating from spirit mediums. Such semipublic displays contributed to Schrenck-Notzing's reputation as “Geisterbaron,” but they also aroused the anger of “critical occultists” who were doubtful about the validity of such phenomena. In the final stages of the credibility contests between parapsychologists and critical occultists, the attention turned from the validity of the observed phenomena to the psychological state of those interested in the paranormal. While initially such inquiries focused on psychological mechanisms of deception and belief, the adversarial nature of the conflict ultimately led to an approach that stressed the psychopathology of parapsychological researchers such as Schrenck-Notzing. Wolffram's book is a thorough exploration of fascinating contests for epistemic authority in which the expertise on the validity of normal and paranormal psychological and physical phenomena was at stake. While her approach cannot explain why people were interested in the paranormal in the first place, it provides important insights into the ways in which cultural authority and scientific expertise were publicly contested in early twentieth-century Germany.