Joseph Delboeuf was a Belgian psychologist and hypnotherapist. He was born in Liège on September 30, 1831, and died in Bonn on August 13, 1896. He was a professor at the University of Ghent from 1863 to 1866 (philosophy), and after 1866 taught at the University of Liège (Latin, Greek, and psychology). Signs of Delboeuf's influence can be found in many places in Sigmund Freud's work, at least until 1900. The most significant include:

1. Delboeuf treated a woman traumatized by the death of her son. He eliminated her symptoms, which resembled the terrible conditions of his death, by having her relive those experiences several times. Delboeuf explained "how the magnetizer assists in the healing process. He places the subject in a state where the evil has manifested itself and through speech combats that same, recurring evil." Freud discussed this hypothesis extensively in "On the Psychical Mechanism of Hysterical Phenomena"...