Experience needs to be grounded in a subject, the grounds for serving as a subject are broad. For the most part you function with a local and provisional subject - it is suited to what is of concern, contains the relevant motives, histories and connection to larger aims, but is provisional in that it refers all questions of being to a deeper and absent layer. Hence it is easy to conclude that the realities encountered in experience are themselves provisional constructs around a deeper reality etc. There is no telling how many such 'layers' there are, in fact the play within the layers is itself a dimension within experience, nominally existential. The ultimate or original question of being hovers over this, as does that of the original subject, without being engaged in any way by the dazzling play of worlds and layers.