In what follows we shall try, so far as is possible within the scope of this book, to throw light on the nature of this force. Since the direct experience of the dynamic realm constituted by it is based on faculties of the mind other than those needed for the Imaginative perception of the etheric realm, we shall have to examine also the nature and origin of these faculties. This will lead us again to the study of one of man's higher senses, this time his sense of hearing, with the aim of finding the spiritual function that is hidden in it. But our order of procedure will have to differ from the one followed in the last chapter, because it will be necessary first to make ourselves acquainted with the nature of the new force and then to turn to an examination of the sense-activity concerned.