Dylan encouraged us (through his fog and haze of liquor) to 'Rage, rage against the dying of the light" and we interpret the light as our corporeal mortality.  Perhaps the light is the ideals of humanity that make us bigger than our days.  Perhaps the light is a compilation of the gestures that make our lives bricks of a cathedral we're all building, one life at a time, a legacy of civilization that transcends our individual flickers that points to a beacon for all who come after to follow.