Human beings have a tremendous capability for inference. This ability is what allows us to detect threats before they are immediately apparent. For example, blood on the floor in a place of supposed safety triggers a sense of instant dread, and preps the fight or flight response. Dead silence in an area one would expect to hear something can conjure up a sense that somebody extremely quiet is nearby, and nobody else is near enough to help.
The same principle applies to ghostly or haunted residences. The small clues that human life has been present, particularly when one is beginning to become intimate with them (as in the case of moving into a new house), can register at a subconscious or intuitive level. A worn hallway, or a bedroom with scrapes and scratches evidencing moved furniture, allow the individual to begin to put together a meta story that may manifest in time as one or more personalities.
Stories of people waking in old homes to find apparitions of former residents gazing at them are commonplace, as are stories of poltergeists. These events necessarily exist beyond the realms of measurable science, but touch the person experiencing the event deeply. This sense of living in a space belonging to another person can be unnerving, particularly for women, who have a biological drive to create a space for themselves and their families that is safe from unfriendly foreign influences. Vice versa, the sense of sharing a space with a benevolent being, such as a fairy or the spirit of beloved loved one, can give one a sense of connection that transcends daily circumstance.
At the heart of all of these experiences is the organisation of matter. These creatures or beings or spirits are never found in isolation, they do not exist in principle alone. If this were the case, ghosts would roam at will, latching onto new people and objects. But without physical evidence of their existence, whether they be totems left behind, markings on the ground, windows or walls, items of furniture or entire residences of an ancient design and implicit history, you simply do not find them. How often, for example, do you hear of ghosts haunting new homes built on old properties?
I do not believe that ghosts are physically apparent. On the other hand, the sense of trespass and reverence for things that are not quite gone, is quite real. In the past, those who disrespected the dead could expect to be ostracised or physically punished. This could explain why people with an anti-social bent tend to hold the supernatural in contempt. Vice-versa, it would explain why people with a connection to the supernatural tend to crave social engagement, to share their experiences. The social value of earnestly experiencing such a phenomenon is undeniable, particularly in more communal or tribal societies.
Look at shamans, priests or imams, even politicians. They tap into this valuable linguistic power when they take their collective subjective experience and draw from it a spirit of the moment, a Zeitgeist that lends credibility and legitimacy either to themselves, their group, or their anointed leader. Throughout the world, military leaders have relied on the verbally adept class to verify their right to rule, in return for the support of the state and often the suppression of competing ideologues.
I make these assertions not out of base skepticism, but out of a respect for the persistent traditions of the mystic. The ability to sense the world’s evidence, look beyond it to infer a wilful spirit’s existence, and to convey deep understanding of that spirit, is a powerful thing.