The case of Nicolai and spectral illusions theory
By Shane McCorristine
In 1799 Christoph Friedrich Nicolai, a Berlin bookseller and philosopher of a sceptical disposition, read a paper to the Royal Society of Berlin entitled ‘A Memoir on the Appearance of Spectres or Phantoms occasioned by Disease, with Psychological Remarks’. After its translation into English in Nicholson’s Journal of Natural Philosophy, Chemistry and the Arts in 1803, it attained status as a paradigmatic case throughout the psychological literature of 19th-century Britain.
Following a diagnosis of “violent giddiness” due to excessive study, Nicolai was accustomed to being bled twice a year by his physician. But Nicolai inadvertently missed his appointment in the second half of 1790, with intriguing results. One morning in February 1791, during a period of considerable stress and melancholy in his life, he saw the apparition of a deceased person in the presence of his wife, who, however, reported seeing nothing. This apparition haunted him all day, and in the subsequent weeks the number of these ghostly figures increased. However, Nicolai resolved to coolly use his powers of observation to study the phenomenon and attempt, if he could, to trace its cause.
When the apparitions began to speak to him, he resolved to be bled by his physician, and leeches were applied to the anus one April morning. Almost immediately, Nicolai noted the acute link between his physiological condition and the spectacle of phantoms that haunted his sensual world: his awareness of the apparitions swarming around him in the surgical room gradually disappeared and by the afternoon of his bleeding the ghostly figures seemed to move more and more slowly, then became paler, and had finally dissolved into the air by the evening. Ruminating upon this very graphic illustration of the connection between bodily disequilibrium (in the form of disordered venereal circulation), the natural vivacity of the imagination and the appearance of spectres in the visual sphere, Nicolai described it as a lesson for philosophers and sceptics to be both more credulous of accounts of ghost-seeing and at the same time less credulous of such phenomena that show “how far the human imagination can go in the external representation of pictures; it may also admonish those well-disposed persons not to ascribe to their visions any degree of reality, and still less to consider the effects of a disordered system, as proofs that they are haunted by spirits”.
Modelling himself on the new breed of psychological investigators, Nicolai distinguished his response to the appearance of ghosts from those of the insane, the fanatical, the superstitious or the lovers of the marvellous, who would readily impart reality to such hallucinations, while he “made them subservient to my observations, because I consider observation and reflection as the basis of all rational philosophy”.
This decision by Nicolai not to ascribe any objective reality to his visions, not to believe in what he saw and what was presented to his senses, proved a landmark, showing the length to which practitioners of the new empirical psychology were prepared to go in the pursuit of knowledge of the internal and external worlds. In contemporary cultural terms it also demonstrated a courageous amount of faith in the powers of self-observation and the strength of the medical imagination to map out the gothic shadows of the psyche. Nicolai’s memoir provided medical philosophers with a lucid example of “with what delusive facility the imagination can exhibit not only to deranged persons, but also to those who are in the perfect use of their senses, such forms as are scarcely to be distinguished from real objects”. The notion that a person could dream while awake seemed like an uncanny contradiction in terms, yet it is clear that in Nicolai’s narrative the sensual objects perceived by the ghost-seer were taken as the objects of the dream world: valid and yet false. Nicolai reasoned ‘as if’ he were awake by discounting the phenomena in his sensual field and exercising the use of enlightened reason. Inaugurating the psychological investigation of visual hallucinations, the case demonstrated the startling potential for the blending of separate spheres of human experience previously considered inviolable and self-contained.
Coming at the turn of the 19th century, Nicolai’s narrative highlighted the huge challenge that ghost-seeing would present to the empirical philosophies of the time due to the fact that ghost-seers appealed directly to the evidence of their senses to support their claims of supernatural visitation – most frequently the evidence of the sense of sight, considered the most veridical human sense. Furthermore, Nicolai’s grounding of abnormal perception in the specific conditions of the subjective imagination raised disturbing questions about the subjective nature of human vision and the simultaneously atomised and permeable characteristics of human psychology. It is with this case, obsessively returned to throughout the 19th century, that the ghost-seer enters the modern age as a figure haunted by his own projections.
The translation of Nicolai’s narrative into English in 1803 contributed greatly to the formation of spectral illusions theory, a rationalist and sceptical theory that maintained an intellectual continuity and ideological consistency in the British medical imagination until the spread of spiritualism in the 1850s. Drawing upon the tradition of the sceptics who had attacked belief in witchcraft in the 17th and 18th centuries, these works rehearsed well-known cases of mass delusion and fallacious perception, often alarmingly dismantling any confidence in the capacity of the human mind to accurately interpret the world around it and to distinguish fact from fiction. Two of the most influential studies upon the nature and origin of hallucinations in the early 19th century centred their examinations on the supposed sighting of apparitions and phantoms of the dead.
In An Essay Towards a Theory of Apparitions (1813), the Manchester physician John Ferriar wrote that apparitions could be explained by what he termed a “renewal of external impressions” through which a visual memory could be reanimated via the visual sense. Indeed, Ferriar extended the principle of a renewal of external impressions to liken ghost-seeing to benign aesthetic states such as dreaming and artistic composition, describing them as waking dreams because they were “composed of the shreds and patches of past sensations”. Samuel Hibbert in Sketches of the Philosophy of Apparitions; or, an Attempt to Trace Such Illusions to Their Physical Causes (1824) enlarged upon Ferriar’s writings and outlined the similar thesis that “apparitions are nothing more than ideas, or the recollected images of the mind, which have been rendered as vivid as actual impressions”. Agreeing with Ferriar that ghosts could be understood as waking dreams, Hibbert used analogies with the chemical world to illustrate the changeable nature of the individual’s mental state, such as the intoxications of dangerous miasmas and the “visionary world” induced by exposure to nitrous oxide. A recurring reference point in Hibbert’s text was that the “renovation of past feelings” through association to a certain level of intensity could produce apparitions in the mind of the percipient.
Through stressing the optical sense in their theories of spectral illusions, Ferriar and Hibbert supported those who argued that such visual phenomena had a peripheral origin in the brain. They stressed that people who experienced spectral illusions were neither insane nor ghost-seers, but merely peripherally affected by abnormal impressions and could be treated by such down-to-earth methods as bleeding and the application of active purgatives. The secular implications of theories that anchored the supernatural in the venereal fluctuations of the body were easily detected by contemporaries. One physician recorded the case of a gentleman from Silesia who was “liable from time to time to a hemorrhoidal flux” and who was followed all over his house, and into bed, by a “spectral company” that included his niece and her husband. Whereas in previous centuries such an episode would have elicited a variety of supernatural interpretations, in this case the prescription was more down to earth: “Gentle laxatives; bathing of the feet; and afterwards a tincture of cinchona restored him to his usual state of health”.
It is clear that these physiological theories of visual hallucinations formed the basis for later psychological theories based upon the similarities between the phantasmagoric nature of the dream world and the ghost-seeing experience, for by withdrawing the origins of ghosts from the supernatural world these theories laid responsibility for such marvels on the occult workings of the human mind. By the mid-19th century it was argued that it was in the “shadowy border-land betwixt physiology proper and pure psychology that apparitions wander” and the debate in English and French psychology became not whether these perceptions were veridical or not but whether they had a central or peripheral origin in the brain.
Dr Shane McCorristine is a Fellow at the Rachel Carson Centre, Ludwig-Maximilians-Universität München, Germany, and Visiting Research Fellow at the Institute of English Studies, University of London.