Truly the universe is full of ghosts, not sheeted churchyard spectres, but the inextinguishable elements of individual life, which having once been, can never die, though they blend and change, and change again for ever.
H Rider Haggard

My father used this quote to reassure me, when I was a child, that ghosts could not hurt me.  They are not frightening - just 'elements' of the person or people that have died - a type of memory that takes form.  These ghosts live by us and watch over us.  They brush past and remind us of their lives; their stories.  They gaze, with interest, being part of our lives; our stories.