Although the very term 'ghost' suggests a sliding towards the supernatural and the marvelous, away from more material and ambiguous 'unrealities' of the fantastic, the effect of ghost tales is similarly disturbing, for they imply the return of the dead as the undead. They disrupt the crucial defining line which separates 'real' life from the 'unreality' of death, subverting those discrete units by which unitary meaning or 'reality' is constituted. Gillian Beer describes the ghost story as a form eliding 'the distance between the actual and the imagined' so that 'frail and cherished distinctions collapse.' In the place of these discriminations appears a space, an absence of difference:
[With the ghost story] the fictional takes place in the everyday: it takes space, and it is this usurpation of space by the immaterial which is one of the deepest terrors released by the ghost story . . . Ghost stories are to do with the insurrection, not the resurrection of the dead.
By attempting to make visible that which is culturally invisible and which is written out as negation and as death, the fantastic introduces absences. Hence the tendency of fantasy towards non-signification. There can be no adequate linguistic representation of this ‘other’, for it has no place in life, and it is this contradiction which gives rise to the disjunction between signifier and signified which is at the centre of the fantastic.
Rosemary Jackson, Fantasy: The Literature of Subversion