Experiences often labeled 'mystical' may not be a unique, special category but rather a form of ego dissolution—an alteration in the sense of self—similar to changes induced by psychoactive drugs and meditation. The idea that mystical experiences are sui generis rests on two self-report scales that operationalize a metaphysically untestable construct. To better understand unusual experiences across disciplines and cultures, new self-report measures are needed that separate generic descriptions of experiences from how individuals appraise their valence, significance, cause, and long-term effects.
William James's The Varieties of Religious Experience struggled to be understood by contemporaries because it was unclear whether it was science or theology. James used an ambiguous concept of the subconscious to bridge religion and science, but this alone does not explain the book's obscure overarching question, its emphasis on psychopathology and unusual experiences, or its many examples and sparse argument. Reading the book in the context of the transatlantic network of experimental psychologists and psychical researchers, especially Frederic Myers, clarifies its underlying question.