William James' Varieties of Religious Experience is a series of lectures the great psychologist delivered in 1901-1902 on the subject of the existential phenomena of religious experience. James notes that as a psychologist he is not prepared to investigate religion from an anthropological or historical perspective. He comes to it instead as one who is interested in everything that pertains to man's "mental constitution" and assumes that "the religious propensities" would not be any less interesting than other phenomena of that type (4). James' source material for his investigation is the writings of individuals whose spiritual lives have been recorded. These exceptional religious people are those for whom, unlike the "ordinary religious believer, who follows the conventional observances of his country," religion is not habitual but exists "as an acute fever" (9). The religious propensities of these people have a directness and intensity that offer the observer of these phenomena a clearer view of what makes up the religious experience.
But these states of religious involvement are often extreme and include many features--hearing voices, obsessiveness, trances--that, ordinarily, "are classed as pathological" (9). James does not, however, subscribe to what he calls "medical materialism," a reductive approach which holds that since every phenomenon of the mind has "some organic process as its condition," these phenomena have no meaning beyond their status as manifestations of physical states (17). As James argues, if one were to accept this argument it would be necessary to say that no mental product--thoughts, feelings, ideas--"could retain any value as revelations of the truth" (17-8). He even goes so far as to suggest that the predominance of such unusual states in the experience of religious persons may indicate that "the neurotic temperament [may] furnish the chief condition of the requisite receptivity" for such inspira...