"It said: 'I am the invisible nonentity. I have affinities and am subtle. I am electric, magnetic, and spiritualistic. I am the great ethereal sigh-heaver. I kill dogs. Mortal, wilt thou choose me?'" Sir Arthur Conan Doyle
Stories of ghosts are observed in every culture. Every child has pretended to be one. Countless stories and movies have starred them, and now the trend is to hunt them with scientific equipment, because if we use scientific equipment then we must be doing science!
Now, I won't say whether I believe in ghosts or not. I've known many people who swear they've encountered ghosts. Even Vermont's own police academy is said to be haunted and many say they've dealt with Mary during their overnight visits. Whether we believe or not is really not the point. The point is could we prove they exist or do not exist in a court of law? Could we prove beyond a reasonable doubt that a house is haunted?
Proving something does not exist or did not happen is nearly impossible so we'll eliminate that aspect. Indeed, even our legal system has been changed so that the defendant does not have to prove that they did not do something, because how is that possible? How do you prove a negative?
Instead, let's talk about proving their existence. There are several wildly popular shows using "science" to investigate the paranormal. They have their scientific tools and they use these to profess that what they are doing is science. However, just as holding a scalpel does not make you a surgeon, holding an EMF recorder does not make you a scientist. In fact, Ghost Hunting Kits are sold in many places. For $160 dollars you too can be an expert paranormal investigator!
Ghost Hunting tend to focus on several measurements, they look for fluctuation in electromagnetic fields, changes in temperature, strange drafts or breezes and abnormal photographic or phonic recordings. Why? Because places that have stories of hauntings have these variations. Therefore these variations must mean there are ghosts present. There's a problem with this logic.
Let's try a hypothesis, shall we? I have been to resorts in Mexico. At these resorts many people exhibited signs of impairment including euphoric behavior, fine motor skill impairment, slurred speech etc. Therefore, Mexican resorts cause impairment. If I go to a house and see this same behavior then I know that I am in a Mexican resort. Tada!
This is very similar to the observations and measurements made by Ghost Hunters. First off, the Ghost Hunters lack a control group. Measurements of the same nature should be made in houses which have not shown any signs of haunting. Do these same EMF fluctuations exist? Are there cold spots? Strange drafts? I live in an old farm house that I have never, ever observed paranormal activity in, and I can tell you, we have cold spots and drafts. If these same measurements exist in the control group then they are not linked directly to ghostly activity and should be discounted as indicators. Just as signs of impairment should not be used as an indicator that we are at a Mexican Resort.
Control groups are always used in any credible scientific study. In terms of impairment the control group is typically the same group of individuals before they have been administered an impairing substance. Therefore you isolate the number of variables at any one time.
Ok, so there is no control group, do the Ghost Hunters reduce the number of variables? Well, they use the same equipment and presumably the same people to do the measurements so there is no variable there. Of course this leads to a new problem which we will discuss in a moment. However, they move to new locations each time. Each location is different. Are measurements done throughout a long extended period under a variety of factors? No. Is the non-paranormal edge looked at? Is a home inspector brought in?
As Sherlock Holmes said:"How often have I said to you that when you have eliminated the impossible, whatever remains, however improbable, must be the truth?" Of course, they're not trying to eliminate the other reasons. As opposed to trying to prove that something is not correlated as scientific procedure dictates, Ghost Hunters are looking to prove that there is a correlation and this is much simpler to do. Anything you find can be evidence because you say it is so.
Now, as for our new problem. By using the same equipment and the same people the Ghost Hunters are adding a new problem. Reproducibility. Are their measurements reproducible by an independent group as is required in any scientifically valid study? No, of course not. That would not be good tv.
I could go on, but for the sake of brevity let's leave it at this: The evidence of ghosts obtained by shows like "Ghost Hunters" would not be sufficient to prove ghostly existence in a court of law. Scientific procedure is not followed and as of yet I would say there is no scientifically or legally valid proof that ghosts exist.
However, I would be interested in seeing someone do just that.