Overview

Alvarado’s scholarly career centered on the historiography of mediumship and spiritualist phenomena, with particular emphasis on recovering and contextualizing the theoretical, experimental, and conceptual contributions of nineteenth and early twentieth-century researchers. Rather than conducting laboratory experiments himself, he functioned as a historian and archivist of the field, systematically examining published and archival sources to document how mediumship was understood, investigated, and theorized across different national traditions and intellectual contexts.

His work demonstrated that the history of mediumship research is far richer and more intellectually sophisticated than standard accounts suggest. Alvarado recovered overlooked theoretical frameworks, identified priority claims that had been misattributed in the modern literature, and showed how spiritualist and psychical researchers grappled with methodological and conceptual problems, such as fraud detection, the distortion of communications, and the role of the medium’s own mind, that remain relevant to contemporary parapsychology.

Early spiritualist discussions about the distortions of mediumistic communications

One of Alvarado’s most significant historiographical contributions was documenting early spiritualist theories of mediumistic distortion. In a 2020 commentary, he recovered nineteenth-century spiritualist writings that addressed a problem still debated in modern parapsychology: how can we distinguish between information conveyed by discarnate spirits and information filtered through the medium’s own mind?¹

Alvarado showed that American Universalist minister Samuel B. Brittan, writing in 1852, had already articulated a sophisticated model of mediumistic distortion. Brittan argued that spiritual influence “usually conjoins itself to, and becomes cooperative with, the predominant elements of the mind” of the receiving person, such that the medium’s habitual patterns of thought and expression would inevitably shape the form and content of any communication. Similarly, social reformer Adin Ballou recognized that mediums of “inferior intellect” would necessarily bias communications through their own prejudices, imagination, and conceptual limitations, a problem Ballou compared to a message passed through an ignorant translator.¹

Even the famous clairvoyant Andrew Jackson Davis acknowledged that the human mind, shaped by education and custom, would “unconsciously alter, modify, and arrange all impressions” in accordance with its own state of development. These early spiritualist writers thus anticipated modern discussions of how the medium’s psychology, expectations, and cognitive abilities might contaminate or distort ostensible spirit communications, a theme that would later occupy psychical researchers and parapsychologists concerned with the super-psi hypothesis.

Physical phenomena and materialization

Alvarado’s historical work on materialization phenomena illuminated a distinct research tradition in French psychical research. In a 2021 essay review, he examined Antonio Leon’s monograph on ectoplasm experiments conducted at the Institut Métapsychique International during the 1920s, showing how French researchers such as Gustave Geley and Juliette Bisson pursued systematic investigations of physical phenomena with documented controls and fraud precautions.³

Alvarado noted that opinions about materialization had always been diverse. Frank Podmore expressed skepticism about the phenomenon in his nineteenth-century review, while Rudolf Tischner acknowledged “circumstantial evidence of considerable strength” without claiming strict proof. Charles Richet, by contrast, argued that materializations could “take a definitive rank in science” even if the mechanism remained utterly mysterious. Alvarado’s historical analysis revealed that the French school of psychical research, centered on physical phenomena like materializations, operated alongside and somewhat independently from the English school’s focus on mental phenomena such as telepathy and automatic writing.³

Alvarado also examined W. J. Crawford’s early twentieth-century studies of physical mediumship with Kathleen Goligher. He noted that Crawford, while conducting careful weighing tests and observations of telekinetic phenomena, failed to situate his work within the existing conceptual tradition of mediumistic forces and radiations that earlier writers had proposed to explain telekinesis and materialization. This historiographical oversight meant that Crawford’s readers might mistakenly believe his theoretical ideas were novel, when in fact they drew on decades of prior speculation about vital forces and the exteriorization of nervous energy from mediums’ bodies.⁷

The living-agency hypothesis in historical context

A major historiographical achievement was Alvarado’s documentation of the living-agency hypothesis, the proposal that mediums’ own extraordinary psychic abilities (telepathy, clairvoyance, or what modern parapsychologists call “super-psi”) could account for veridical mediumistic communications without invoking discarnate agency. Modern scholars had often attributed the origin of this idea to late-nineteenth-century members of the Society for Psychical Research, particularly Frank Podmore. However, Alvarado demonstrated that the concept appeared much earlier, in the spiritualist and mesmeric literature of the 1850s and beyond.²

Alvarado identified early writers such as Carl Gustav Carus, Edward W. Cox, Justinus Kerner, Asa Mahan, André-Saturnin Morin, Maximilian Perty, B. W. Richmond, and Edward C. Rogers who had already discussed the possibility that mediums might obtain information through their own psychic faculties rather than through spirit contact. Notably, these early discussions often invoked physical forces (concepts of nervous force, vital energy, and ether-mediated transmission) rather than the later psychical researchers’ more abstract notion of psi. This recovery of priority corrected the historiographical record and showed that the intellectual problem of distinguishing mediumistic information derived from living agents versus discarnate communicators had been recognized almost immediately after the rise of Spiritualism in the 1840s.²

Institutional and international developments

Alvarado’s work documented how mediumship research developed across different national and institutional contexts. He examined the role of psychical research in mainstream intellectual journals, showing that discussions of mediumship, telepathy, and mental suggestion appeared in prestigious publications such as the French Revue Philosophique de la France et de l’Étranger, founded in 1876 by Théodule Ribot. Authors including Théodore Flournoy, Charles Richet, Pierre Janet, and Julian Ochorowicz published on mediumship and related phenomena in this journal, which served as an important forum for French psychology and the social sciences.⁸

Alvarado also traced the inclusion and eventual exclusion of psychical research from the International Congresses of Psychology held between 1889 and 1905. Prominent researchers such as Frederic W. H. Myers, Charles Richet, Eleanor M. Sidgwick, and Théodore Flournoy presented papers on telepathy and mediumship at these congresses. However, after the 1900 congress, discussion of psychic phenomena declined markedly and was eventually rejected from the congresses entirely. Alvarado interpreted this exclusion as an example of boundary-work, whereby psychology as a discipline sought to professionalize and distance itself from spiritualist associations and phenomena deemed scientifically disreputable.⁵

His 2021 essay review of Andrea Graus’s book on spiritism and mediumship in Spain (1880–1930) further demonstrated the international scope of mediumship research. Alvarado showed how Spanish spiritualists and physicians engaged with mediumship investigations, developing local research traditions influenced by French spiritism and contributing to the broader European conversation about psychic phenomena.⁹

Historiographical method and recovery

Alvarado’s approach to the history of mediumship exemplified rigorous historiographical scholarship. Rather than imposing modern categories or dismissing older work as superstition, he examined primary sources on their own terms, identified the conceptual problems researchers were addressing, and recovered overlooked contributions to theoretical understanding. His work on early reference works, such as his analysis of Nandor Fodor’s Encyclopaedia of Psychic Science, demonstrated the value of bibliographic and archival recovery for understanding the scope and sophistication of pre-1930 psychical research.⁴

Alvarado also recovered early instrumental and physiological approaches to mediumship. His note on John E. Purdon’s sphygmographic studies of pulse synchrony in the early 1880s illustrated how nineteenth-century researchers attempted to detect putative psychic connections through objective physiological measurement. Although Purdon’s work employed concepts of nervous force and ether transmission that modern parapsychology has abandoned, Alvarado recognized it as a precursor to contemporary psychophysiological indices of psi functioning.⁶

His essay on investigating mental mediums drew on the historical literature to suggest research topics and methodological approaches for contemporary scholars. Alvarado emphasized the complexity of mediumship as a psychological and phenomenological process, arguing that in-depth single-case studies and interdisciplinary approaches would deepen understanding of mediumistic trance, mentation, the dramatic capabilities of the subconscious mind, and the relationship between mediumship and dissociative or psychopathological states.¹⁰