The problem of ghost instantiation, or “haunting” has increased substantially in recent decades. As the world population rises, so too does the number of deaths reported annually, and therefore the number of ghosts. More efficient exorcism techniques are urgently needed, especially as the evidence base for traditional or complementary exorcism techniques remains weak. In this paper, we propose a new exorcism method, illustrate its application with a case study, and discuss its suitability to a wide range of spectral phenomena.
Although the mortality rate has dropped substantially over the last century, the sharp increase in population means that the absolute number of deaths is at its highest level in recent times (Figure 1), and is expected to increase for at least the next century. This is especially evident in developing countries, where both birth and death rates remain high.
The economic effects of hauntings, including reduced productivity, supply chain disruption and depressed land value, reduce global GDP by around 6%, and the physical and mental toll of ghost attacks puts significant strain on healthcare systems. An effective development program for developing regions requires an efficient public exorcism campaign, along the lines of health and education schemes already organised by NGOs.
The haunting epidemic has been ongoing for as long as humanity itself has existed, and the ceremony of exorcism is believed to be a universal practised by all human cultures. All major organised religions in the Abrahamic (West Asian), Dharmic (South Asia) and Taoic (East Asian) categories have sects that have codified exorcism rituals. These rituals are usually led by religious leaders and are of some effectiveness expelling ghosts from buildings and other enclosures.
However, traditional exorcism methods are focused on the supposed expulsion of ghosts possessing human beings. Research has revealed that the vast majority of cases of alleged possession are in fact untreated mental illnesses, and religious exorcism methods risk doing great harm to people in need of psychiatric care. The rare cases in which a person does genuinely contain an external spirit capable of doing harm require special treatment from mental health and spiritual professionals working together, and are beyond the scope of this article.
There are a number of factors in traditional exorcisms which together have been found to be effective at driving ghosts from properties:
Appeals: Chants and ritual readings during exorcisms typically appeal to the ghost directly, exhorting them to leave on behalf of another power. These appear to be most powerful when invoking the names of beloved friends and relatives, or of a higher power respected by the spirit, such as a political or religious leader. The most widely accepted explanation for this is the “basal mind hypothesis”: although most ghosts lack higher functions, a substrate of language processing facility remains, and appears to be capable of parsing and reacting to especially strong statements. Success here depends on knowing how to appeal to the ghost’s instincts, and the rise of agnosticism and non-belief and of the elderly living alone outside the family have made it harder for exorcists to determine the best approach.
Sensory overload: Loud noises (songs, screams, drums, bells, gongs), vivid images (burning flames, bright flowers, dances and other physical rituals) and powerful smells (incense, burnt offerings) are common elements of exorcism practices. According to the basal mind hypothesis, these powerful stimuli penetrate the ghost’s mind and either disrupt its thought processes or trigger a “fight or flight” response. The latter explains why in some cases exorcisms fail and cause the ghost to become even more violent – if a ghost feels threatened, it can fight back with tremendous power.
Purification: Cleansing has always played a major role in exorcism rituals. Many chemicals used in exorcism have solvent or disinfectant properties, including water (holy water is typically derived from artesian wells, hence its purity), oils, alcohol, salt, medicinal herbs and ashes. Similarly, burning has always been considered an effective last-resort for destroying especially hard-to-exorcise objects or buildings. In addition, many exorcism rituals lay heavy emphasis on air movements, from the Catholic practice of insufflation to the Shinto use of paper fans known as gohei. Cleansing the haunted environment removes contaminants that anchor ghosts the location, and strong air currents can disperse gaseous or ionised ghosts.
All exorcism rituals draw on these three building blocks. However, across cultures these rituals are applied inconsistently. Experimental data on the most effective techniques is often ignored, and technological solutions are rejected in favour of less reliable traditional tools. There is clear scope to improve exorcism practices using the latest advances in the fields of sensing, robotics, and artificial intelligence.
To improve the outcomes of exorcisms of buildings and spaces, a new process is proposed. This process consists of five stages:
Risk assessment. A thorough analysis of the haunted space is always required before any exorcism can begin. The history of the space should be determined, and if possible the religious faith and political alignment of the ghost should be found. If the ghost has living relatives, they should be consulted as part of this process. A clear danger during exorcisms, as demonstrated in many case studies, is that the exorcist and often other witnesses are present in the ghost’s area of influence. This puts them at considerable risk. Using triangulation and aural boxing methods to determine this area before beginning the exorcism considerably reduces the risk to participants. Where possible, this should be done with unmanned drones (see point 3).
Area closure. Once the ghost’s area of influence has been determined, the next step is to seal this area as much as possible. Portable high-intensity work lights should be used to ensure that all areas are well lit and no shadowy recesses remain from which a ghost could leap. Doorways and windows should be sealed with hermetic oil-coated rubber gaskets where possible – where access is required, the doorway should be protected by an air curtain of fast moving (at least 20 ms-1) air, set up so that all airflow is towards the haunted space, not away from it. Similarly, all ventilation systems should be deactivated and sealed or, where not possible, fans should be placed to ensure a constant air flow into the haunted space.
Area denial. The ghost’s area of influence can now be reduced. Here, robotic and remote controlled vehicles are essential to ensure the safety of the human operators. The authors have constructed a set of armoured wheeled drones equipped with bright lamps, incense burners, loudspeakers and fans. These are driven into the peripheral areas of the ghost’s influence and activated. These drive the ghost into the the recesses of the area. While the ghost is in retreat, the air curtains can be moved to close off new areas. By repeating this process, the ghost can be confined to a single room.
Spectral dispersion. Once the ghost is cornered, it can be removed. Ghosts that respond well to human influence should be addressed over the loudspeaker and commanded to leave in the name of whatever deity the ghost reveres. Those that are unresponsive must be dispersed physically. Gaseous spirits can be targeted with directed blasts of air, while ionised spirits are more disrupted by electromagnetic pulse (EMP) delivered from an on-board vircator.
Purification: The ghost may have left many contaminants in the environment, which can lead to repeat hauntings if not thoroughly removed. Human remains that gave rise to the ghost must be removed – in many cases, these may be buried in a long forgotten graveyard upon which the current structure was built. Ground penetrating radar helps these remains be found for exhumation and reinterment. Ectoplasm must be thoroughly washed with ecto-digesting enzymes and directed jets of hot water. Silicon-rich dust should also be removed, as it can give rise to ghostly phenomena during thunder storms. What cannot be cleansed should be incinerated.
By following these steps closely, buildings and other spaces can be exorcised within hours in a safe and thorough manner.
Case studyThe efficacy of this method is demonstrated in the exorcism of a haunted property in the United Kingdom (the exact location cannot be disclosed for data protection reasons). This property consists of a large terraced house in poor condition (Figure 2), abandoned 21 years prior to the exorcism due to persistent disruptive haunting events including screaming, destruction of Christian imagery, blood running from plumbing, and the appearance of burned animals in unoccupied rooms. Repeated attempts to exorcise the structure by Christian (Catholic and Coptic), Jewish (Kabbalah) and New Age (Wiccan) methods were unsuccessful, and resulted in three hospitalisations and five crises of faith.
As part of the risk assessment, the investigators found the original deeds of the house. The property had been constructed on a former Viking graveyard, meaning that the ghosts were likely Norse in origin.
Being unable to find an Old Norse speaking exorcist, nor any practitioner of the Scandinavian religion capable of exorcising such a thoroughly haunted structure, the authors’ methodology proved to be the only practical solution.
A drone carrying a bloodied wolf’s fang and a curse written in runes was flown in the vicinity of the building. Spectral activity (air movements, moans, electromagnetic disturbances) was detected when the drone came within 1.4 metres of the building or ventured into the airspace of the back garden. Intense spectral activity (violent movements, damage to furniture and structures, demonic faces on the live camera feed) was detected when the drone approached the upstairs bedroom, which had previously been reported as the centre of the haunting. Shortly there after, control of the drone was lost. It flew towards the operators with impossible speed, but collided with the bulletproof glass window of the mobile control centre and was destroyed.
Now that the ghost’s area of influence was ascertained, work began to seal the property. The loss of control of the drone indicated that the ghost had some degree of electromagnetic influence and was therefore likely an ionised spirit. For this reason, the clockwork rover (Figure 4) was deployed in the first instance. This rover has no electrical parts – all logical and mechanical circuits use clockwork mechanisms, with power supplied from a wound mainspring. The inside of the rover is flooded with non-flammable lubricating oil in order to prevent ghosts from instantiating ectoplasm inside the body and jamming the mechanism.
Using the rover, windows were filled with sealant resin, and larger broken panes covered with thick adhesive plastic sheets. Two air curtains were set up over the front door in an airlock formation. The rover was then deployed in the building with a limelight burner inside a safety glass cover. The intense light of the burning calcium oxide illuminated the downstairs hallway, driving away the ghost and allowing technicians to enter the building and set up fans and fixed work lights (Figure 5) to prevent the spirit from travelling down the staircase.With the ghost excluded from the staircase area, an electric-powered walking robot was deployed to climb the steps (Figure 6). The walking robot was defended with floodlights, an EMP generator and air jets mounted in its fingers. Nevertheless, a second clockwork rover was deployed at the top of the stairs from the walking robot, in order to clear the landing of spiritual presence. Once safe to do so, the walking robot entered the landing. Operators noticed a painting on the northern wall – closer investigation revealed it to be a print of “Hermod before Hel” by Hélenè Guerber (Figure 7), showing the heroic Hermod meeting the death goddess Hel. The infernal Norse motif had clear connections to the present haunting, and it was deemed essential that this painting was removed. A solution of turpentine was used to wash the printed image off the paper, which was then shredded with the robot’s onboard drill (Figure 8). With the painting destroyed, measured electromagnetic and vibrational disturbances dropped considerably. Thermal imagery and radio reception revealed that the ghost was now entirely penned in the bedroom Technicians were able to enter the upper storey bearing lights and fans, wind up the clockwork rover again, and deploy it into the bedroom, centre of the activity. The initial response of the spirit to the intrusion was violent lashing out. The bedstead appears to have been lifted into the air, folded into a ball of splintered oak and twisted iron, and then thrown directly at the rover. Although the safety glass held, the flow of oxyhydrogen was interrupted and the limelight went out. The rover was then thrown through the window of the bedroom, smashing the window coverings, and landed on the road, causing considerable damage to two parked cars. Several scatological Norse phrases were heard, and a fountain of blood erupted from the chimney, reaching a height of 76 metres and soaking properties across the neighbourhood.
To seal the hole quickly, a spotlight was brought to bear on the balcony, producing a zone of bright light difficult for a ghost to cross. Technicians then worked to raise a wind machine high enough to establish an air curtain across this window. The walking robot meanwhile focused all of its defensive tools on the bedroom door.
Once the air curtain was established, and tests showed that the ghost was still restrained in the bedroom, the walking robot deployed its grenade launcher tube and fired two shells into the room: one containing a compressed mixture of essential oils of pine needles, juniper and heather, chosen as traditional Norse incenses, and one with a magnesium flare, producing approximately twenty seconds of blindingly intense light. The loudspeaker played recordings of Norse blessings at 120 dB.
As the light began to decrease, the walking robot was directed into the room carrying the largest fan at full power and released a one-second 15 kW EMP into the room. Thermal imagery of the room revealed the ghost’s form was totally dispersed by the electric shock. A hose was introduced through the window, and the air in the room was sucked out into a multichambered vessel to keep the ghost’s vaporous elements separated.
With the immediate apparition resolved, work turned to ensuring the haunting would not repeat. The floorboards were taken up and a digging robot was deployed to search for bodies. The grave of a Viking shieldmaiden was discovered, and ground piercing radar showed that the skull still bore a helmet identical to the one seen in the drone imagery. The body was exhumed, and was given a traditional funeral at an undisclosed site on the East Yorkshire coast one week later. No hauntings have been reported since, and the house is now home to a successful nail salon.Discussion
The exorcism procedure outlined in this paper shows promise for many of the most common haunting types. Care needs to be taken at all stages to ensure that the correct methods for the spirit in question are used, and operators always need to be prepared to deploy emergency containment procedures should a robot be disabled. All possibilities need to be considered – had it been clearer earlier that the ghost possessed the strength to shatter the window coverings, an air curtain would have been established here before beginning the exorcism.
Robot-aided exorcism, based on a standardised, fully risk-assessed protocol, promises great benefits in the field of the busting of ghosts. Commercial solutions are expected to be on the market within two to three years. With rapid deployment, the problem of haunting may be resolved within a decade.
Declarations of interest
The authors declare that they ain’t afraid of no ghosts.
 Derived from World Bank data, Databank, “Population, total” (https://data.worldbank.org/indicator/SP.POP.TOTL) and “Death rate, crude” (https://data.worldbank.org/indicator/SP.DYN.CDRT.IN)
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