A monograph on sleep and dream: their physiology and psychology

The modern endeavour to pursue Psychology, as all the physical sciences are now pursued, by the study of facts and phenomena, instead of by metaphysical abstractions, consulting of inner consciousness and argument à priori, has invested the subject of this monograph with extraordinary importance, because Sleep and Dream are familiar physical and psychical conditions, disputed by none and which cannot be ascribed to prepossession,[iv] dominant ideas, or diluted insanity.