According to the author, psychology of religion should be the study of the personal experiences, tensions, conflicts and resolutions to conflict within a specific, clearly identified religion. The author opposes philosophical-psychological preconceptions which tend to eliminate the proper psychological reality of dynamic conflicts (as e.g. with James and Otto). With Freud, Evan-Pritchard and Needham, he affirms the historical dimension of civilizations and religions, and elaborates its consequences. He examines in this context work by Maslow on extrinsic and intrinsic religion and by Rokeach on mental-psychological dogmatism. He stresses the largely preconscious motivations and processes that are at play in the personal interests and defense mechanisms operating in the various forms of belief and unbelief and in their changes. This preconscious reality is the psychological one par excellence and is the appropriate object for subtle psychological investigations.