The study of paranormal activity has a long and interesting history. Many ancient religions are based on paranormal study, while the metaphysics of many ancient cultures included pantheons of ghosts, demons, fairies, gods and other supernatural phenomenon.
In fact, among the earliest references of ghosts can be found in the Bible's Old Testament. A good example is in the First Book of Samuel (28:7), where King Saul consults the ghost of the dead priest and prophet, Samuel.
In the New Testament, Jesus Christ himself was considered as a "Holy Ghost" when he rose up from the dead and appeared before his 12 disciples.
In ancient Greece, Homer's works, the Oddyssey and the Illiad held many references to Ghosts and Specters prophesying and giving advice to Greek heroes.
In ancient Egypt, the Egyptians wrote the Book of the Dead, which catalogs Egyptian rituals on the proper way of taking care of the souls (or Khu) of the departed.
In Tibet, Buddhist monks wrote the Bardo Thodol as a way of helping the human soul reach Nirvana after death, and to prevent the process of rebirth.
And finally, in Medieval Europe, there is the Malleus Maleficarum, a book written in the mid 1400's which offers insights on how to detect and eliminate witches. Heinrich Kramer, the author of the manuscript, wrote it to refute skeptics who did not believe in the existence of Witches.
Given these examples, it's unreasonable to say that the study of paranormal activity is relatively new. In truth, it's been around since the dawn of civilization.
The only difference is that paranormal investigators in the modern world must prove the existence of the supernatural by using the scientific method, and the presentation of evidence.
Aside from the need of scientific methodology, it's also important to remember that paranormal activity is a broad topic, and is not limited to the study of ghosts and apparitions.
In many cases, demonology, elementals, flying saucers, psychic phenomenon and even monster sightings (e.g. Loch Ness and Big Foot) can be classified as paranormal activity.
It's also important to remember that paranormal investigation takes on many forms. Most of the methodologies used in paranormal studies originated in the 19th and early 20th century.
People like Edgar Cayce and Helena Blavatsky claimed to have used certain methods which allowed them to commune with higher beings and see into the future.
Such claims ultimately sparked the spiritualist movement in America and Europe, and it is from these movements that many studies in paranormal activity originated.
Paranormal books that explained the existence of ghosts, spirits, doppelgangers, poltergeists and haunted houses became common throughout the time of the 19th century.
A good example of this is a newspaper called, The Light, which offered articles on the subject of Ghosts and Spirit Photography.
Another good example is Blavatsky's "The Secret Doctrine," which explains the nature of the soul and the origins of spiritual phenomenon.
Summoning or exorcising spirits - both ghosts and elementals - have been a very important part the Spiritualist movement at that time.
Paranormal investigators as well as members of the Spiritualist movement tried to understand these types of phenomenon using a semi-scientific approach. Ultimately, their theories played a very important role in how people in the western world saw and regarded ghosts and other paranormal anomalies.
For example, theories on ectoplasm as well as the pervasive use of spirit photography were widely accepted theories in the Spiritualist movement at the time. Today, such theories are still quite popular and is widely used in modern Ghost Hunting Societies, and research groups.
The basic idea is that ghosts as well as certain elementals leave behind residual matter called ectoplasm. It is this substance which many paranormal investigators hope to understand and explain.
The idea of ectoplasm is of the theories used by Spiritualists to prove the existence of ghosts via the scientific method. This approach would ultimately determine the path of the Spiritualist movements and paranormal investigation as a whole.
Moreover, theories on the existence of chakra energy as well as the aura have also been used to explain the existence of ghosts and supernatural phenomenon.
Like ectoplasm, Spiritualists believed that they can study paranormal activity by observing and understanding the human aura as well as the chakra.
They believed that telekinesis, precognition and telepathy can best be understood if they can somehow understand the energies which come from the human body whenever such phenomenon occurs.
This is the reason why so many paranormal investigators use devices which can detect energy disturbances.
Even Spirit Photography is based on the idea of detecting ghosts and supernatural entities by using specialized cameras that can capture specific forms of light.
It's worth mentioning that in today's society, there are still plenty of people who are interested in paranormal activity. Indeed, a quick search on Google or Youtube offers countless sites and videos of paranormal activity.
People, like Zecharia Sitchin and David Icke, have significantly expanded the field of paranormal investigation, and have offered new insights into supernatural phenomenon, including ghosts.
Scientists, for example, have put forth theories on geothermal energy and abnormal energy waves in order to explain ghost sightings and other paranormal phenomenon.
Such theories and observations can easily be found on the internet, so it's not hard to find materials on this topic if you're interested in further studies.
However, it is also true that the subject of paranormal activity is dismissed by most people as simple "New Age" nonsense.
Sitchin's book, The Twelth Planet for example, is dismissed by most people as utter nonsense, even though many people also considered it to be a serious work of scholarship.
Moreover, in modern Academia, many consider investigation into Paranormal Activity as an eccentric and useless waste of time.
Despite the dismissive attitude of today's modern world however, the interest in paranormal is not likely to go away. Ghosts, aliens and unusual phenomenon have fascinated human beings throughout history.
And whether or not people will be able to explain such phenomenon, paranormal activity is not likely to disappear in the foreseeable future, and people everywhere will continue to be fascinated by them.
Be sure to check out:Paranormal Investigations: The Proper Procedures and Protocols of Investigation for the Beginner to the Pro on Amazon. Where author Chad Stambaugh discusses the process of trying to find that one piece of evidence that could prove, without a doubt, that ghosts are real.