I've had some very interesting feedback on my Inhuman post. a number of people have reminded me of Hoffmann's intriguing Sandman tale. I hope to write more on issues related to this. In the meantime, let me draw your attention to Hoffmann's tale online here , from which comes this quotation:
'If there is a dark and hostile power which traitorously fixes a thread in our hearts in order that, laying hold of it and drawing us by means of it along a dangerous road to ruin, which otherwise we should not have trod--if, I say, there is such a power, it must assume within us a form like ourselves, nay, it must be ourselves..'