One thing I’ve seen bandied about lately is the use of personal experiences as evidence in a paranormal investigation. Many say that something must have happened because a person witnessed it. But that is a false idea. Looking at the fallibility of human perception can indeed show that there is a good chance that they may have witnessed an event that was totally fabricated by their mind, especially when it involves poor lighting, senses being heightened by adrenaline, as well as psychological contamination.
With human senses, especially concerning vision in low light situations, the possibility of seeing a “shadow person” aren’t that remote at all. In fact, I have seen several cases where someone reports seeing a “shadow person” yet the video evidence collected from a IR camera does not support their report, and actually shows that nothing was there. This can only lead to a few conclusions: A) The person’s eyes played tricks on them, or B) The person’s mind played tricks on them, or C) The event was only detectable by some unknown interface with the human mind.
Now all three of the above examples are possible, but without knowing which one then how can it be used as evidence? Remember, evidence needs to demonstrate whatever the claim is and needs to be a fact. In this case let’s say the cause is ‘A’, the person’s eyes played tricks on them, but our investigator assumes the event is caused by ‘C’. As can be seen in this example, including that personal experience, along with the investigators conclusion, it has steered our conclusion in the wrong direction.
Another problem is a person’s recollection of what they thought happened. A prime example of this is from episode 315 of the TV show “Ghost Hunters”. In that episode, one of the reason’s they used to lay claim that the image of the statuette was paranormal was because of Steve’s recollection and reasoning of how he got up off the couch. But for anyone who’s seen the clip when he explains this will quickly see that his accounts of his arm movement when he gets off of the couch are the opposite of what he recalls.
There is still another issue with personal experiences, and that is they cannot not be reviewed like video evidence can. Currently there is no way to retrieve a memory with technology, and even then with how memories can change over time there is now way to be sure that what would be recalled would be accurate.
What all this boils down to is the fallibility of people. People are very fallible whether intentional or not, and because of that fallibility they cannot be used as a source of credible, verifiable evidence. While personal experiences may be good to note for reasons to investigate a site, they cannot be used to support the idea that the paranormal exists.