The gift and power of one's dreaming mode of existence lies in the circumstance that, as two modes of their one and the same human existence, they are homologous with one another, sharing the same structure, form, concerns, and patterns of a single, meaningfully organized self. The evanescent butterflies of one's dreaming, once seen and understood in their fullness as meaning-bearing beings, have the power, once they are awake, to change the world, not only their world but the world of many others as well. The majority of thinkers before Sigmund Freud considered dreams either to be the result of somatic or environmental stimuli or to be some kind of pathogenic or hallucinatory process; that is, not at all a thematically or structurally meaningful dimension of human existence. The scientific laboratory studies revealed that 'rapid-eye-movement sleep' (REM) sleep and waking modes of being have a surprising number of similar characteristics by a number of physiological and neurological criteria.