José Salvador Fernández was an important Spiritist thinker and parapsychological researcher in Argentina, born in Buenos Aires on 17 February 1893. In his youth, he graduated as a civil engineer from the University of Buenos Aires. He went on to become a distinguished physics teacher at various schools in the Argentine capital and, at the age of 30, published his first book, Problemas de Física (Problems of Physics). His interest in paranormal phenomena and Spiritism began in 1921, when he personally investigated the case of a well-known psychic who conducted diagnostic and healing mediumship sessions. Following this, he became a member of the Asociación Espiritista Constancia, where he carefully observed the mediumistic sessions held by the institution.

In 1933, he carried out research with his wife, María Amanda Ravagnan, who at that time began to demonstrate mediumistic abilities. Together with other collaborators, he founded the Círculo Espiritualista Atman in the same year. Initially, Fernández’s research followed the metapsychical paradigm, characterised by a qualitative methodology. Later, through correspondence with J. B. Rhine, he adopted the parapsychological paradigm, making use of quantitative methods. Fernández was chiefly responsible for introducing the mathematical methodology for investigating ESP (extrasensory perception) phenomena throughout Latin America, both through his own articles and by translating Rhine’s papers into Spanish.

As a parapsychologist, Fernández served as President of the Sociedad Argentina de Parapsicología (1948–1953), the Instituto Argentino de Parapsicología (1953–1955), and the Colegio Argentino de Estudios Psíquicos (1957–1967). José Salvador Fernández also played a prominent role in the Latin American Spiritist movement. In addition to being an active member of his Spiritist society, he was a lecturer, writer, and editorial assistant for the Spiritist journal Constancia. At the First Pan-American Spiritist Congress in 1946, he attended as a representative of the Confederación Espírita Argentina and the Sociedad Constancia, and was elected the first President of the newly established Confederación Espírita Panamericana. He also maintained close ties with Brazilian Spiritists, serving as an Honorary Professor at the Instituto de Cultura Espírita do Brasil (ICEB).

He was a friend, colleague, and research associate of Luiz di Cristóforo Postiglioni (1909–1979), with whom he co-authored the book Fundamentos Científicos-Filosóficos de la Reencarnación (Scientific and Philosophical Foundations of Reincarnation). José Fernández died on 16 May 1967 following a stroke. His greatest contribution to Spiritism extended beyond developing a Spiritist theory of psychic phenomena; it lay in demonstrating the importance of scientific experimentation in the development of Spiritist doctrine through the application of new methods developed by parapsychology to the investigation of mediumistic phenomena.