Dr. Chris French is a Professor of Psychology at Goldsmiths, University of London, where he heads the Anomalistic Psychology Research Unit. Here are some extracts from a write up of his in Guardian of 9th September 2009:
[M]ost people assume that the most reliable evidence of all is that based upon personal experience.....As even brief exposure to the field of anomalistic psychology will reveal, personal experience is often a very poor guide to reality.
Both perception and memory are prone to errors. What we see and hear, especially under less than ideal observational conditions, can be heavily influenced by our prior beliefs and expectations.
Hallucinations are much more common than most people realise. Memory is also prone to errors: many of our recollections are not even distorted versions of events that we have witnessed but instead are complete fabrications.
Anomalistic psychology investigates the imperfections of the human cognitive system that could lead us to conclude that we have experienced the paranormal when in fact we have not.
Because scientists are human beings and therefore susceptible to all of the cognitive biases referred to above, in practice the scientific method is not perfect. But it is the best approach we've got. It is the only approach to truth that I am aware of that at least acknowledges that such biases exist and attempts to control for them.....Furthermore, its reliance upon replicability, self-correction, critical evaluation by peers, and ultimately upon empirical data means that we can legitimately have a higher level of confidence in well-supported scientific theories than in other assertions about the ultimate nature of reality.
[M]ost people believe in the paranormal, a sizeable minority claim to have had direct personal experience of it, and many live their lives in accordance with such beliefs....... evidence suggests that such beliefs may, in certain contexts, provide psychological benefits.
One obvious example is the fact that people who believe in an afterlife, despite the lack of any convincing scientific evidence, will be less afraid of dying. Exposure to anomalistic psychology may not only lead people to question paranormal claims but also to question firmly held religious beliefs. One of the implicit messages of anomalistic psychology is, "Question everything – but use the appropriate critical thinking tools when doing so." For some people, this will be a challenge they prefer not to face.