We usually think of our _mind_ as the aggregate of the various emotions of which we are actually _conscious_, when, in reality, consciousness forms but a small portion of our mentality, the _subconscious_--which is composed of all our past experiences filed away below consciousness--directing every thought and act. Inconceivably delicate and intricate mind-machinery directs us, and our idlest fancy arises, _not by chance_ as most people surmise, but through endless associations of subconscious mental processes, which can often be laid bare by skilful psycho-analysis. Our subconscious mind does not let the past jar with the present, for life would be made bitter by the eternal vivid recollection of incidents best forgotten. Every set of ideas, as it is done with, is locked up separately in the dungeons of subconsciousness, and these imprisoned ideas form the basis of memory. _Nothing is ever forgotten_, though we may never again "remember" it this side the grave. In a few cases we can unlock the cell-door and release the prisoner--we "remember"; in some, we mislay the key for awhile; in many, the wards of the lock have rusted, and we cannot open the door although we have the key--we "forget"; finally, our prisoner may pick the lock, and make us attend to him whether we wish to or not--something "strikes us". Normally, only one set of ideas (a complex) can hold the stage of consciousness at any one time. When two sets get on the boards together, double-consciousness occurs, but even then they cannot try to shout each other down; one set plays "leading lady", the other set the "chorus belle" and so life is rendered bearable. This "dissociation of consciousness" occurs in all of us. A skilled pianist plays a piece "automatically" while talking to a friend; we often read a book and think of other things at the same time: our full attention is devoted to neither action; neither is done perfectly, yet both are done sufficiently well to escape comment. Day-dreaming is dissociation carried further. "Leading lady" and "chorus belle" change places for a while--imaginary success keeps us from worrying about real failure. Dissociation, day-dreaming, and mental epilepsy are but few of the many milestones on a road, the end of which is insanity, or complete and permanent dissociation, instead of the partial and fleeting dissociation from which we all suffer. The lunatic never "comes to", but in a world of dreams dissociates himself forever from realities he is not mentally strong enough to face. The writing of "spirits" through a "medium" is an example of dissociation, and though shown at its best in neuropaths, is common enough in normal men, as can be proved by anyone with a planchette and some patience.