Barbelith Underground > Temple > Ghosts and psychogeography

Hmmm... could be a few possibilities. Unconscious sympathetic magic creating a link between the house itself and its virtual representation? Or perhaps a Lovecraftian sort of thing... the right combinations of angles and curves creating an effect of "wrongness" in the minds of the observers. Or predisposing them towards a certain mental state, which has a tendency to create thoughtforms?

That second one is interesting. Theoretically if it's the case, it should be possible by reduction to arrive at the design for a Platonic haunted house. Every room packed to the gills with spirits...