Mediums impress a lot of people. Believers will swear that their medium must have known something about them or their dead relatives. Something that they could only have learned by communicating with the dead.
The sheer number of testimonials are probably enough to warrant an investigation but everyone knows there are two sides to the story: Believers and skeptics.
On the believer side there are testimonials, biographic accounts from mediums. In short flakey New Age babble. But there are also purported scientific investigations. I will focus on these and examine them in detail.
On the skeptical side, the situation is more complicated. There are a number of skeptical books that will attempt, with greater or lesser success, to give a conventional scientific explanation. Conventional is a bit of a misnomer here, as the idea that one can really talk to the dead is much older than specific attempts to otherwise explain such experiences.
These explanations draw from two sources: magic and psychology. There is specialized literature for magicians of all sorts, including for so-called mentalists. Mentalists specialize in mind reading, clairvoyance and other such tricks. Like other magicians they write up their tricks and sell them.
Psychology meanwhile offers rich insight and explanation for the mental biases and pitfalls, such as ‘the fallacy of personal validation‘, that these tricks use and abuse.
Skeptical books provide a valuable service by collecting together these varied bits of information and making them easily accessible but they are not in themselves science.
From time to time, skeptical tests of mediums happen. These aim not at establishing how the medium does its business but only at testing if the medium can at all perform the paranormal feat he or she claims. Since mediums routinely fail, they aren’t much of an investigation into mediumship. They just fail to find anything to investigate.
The Great Asymmetry
There is a great asymmetry between these two sides. Believers undertake extensive investigations of mediumship while skeptics fail to find anything they could possibly investigate in the first place. Much research into how people fool themselves has been and is carried out by psychology but under completely different labels.
This may fool a novice investigator into believing that believers have studied the issue more thoroughly and have more to say. In fact, believer investigations are more extensive because they ignore the already existing literature. They make error after error, all too often only correcting them after having had their noses rubbed in it.
That pattern is not unique to mediumship but found across parapsychology. Still, there are notable exceptions but that’s for another time.
Now enough about the bickering. Let’s get to the facts.
As this is a very extensive topic, I’m breaking it down into multiple parts. Links will appear here as they become available.