Nickell starts, in his Introduction, by trying to define what is meant by a ghost. In this book he is mainly concerned with reports or stories about ghosts which are generally believed to be manifestations of spirits of the dead. He states that he has spent more than four decades investigating the belief in ghosts, looking for "solid evidence" as to whether ghosts are real or merely figments of the human imagination.
What is not clear to me, however, is what qualities real ghosts would have, as distinct from all the misperceptions, delusions, folklore, lies and fantasies. How could one obtain "solid evidence" of ghosts? The impression that ghost hunters do not seem to know what they are looking for in seeking "real" ghosts is highlighted in the discussion of the fact that most people who say they have seen them describe them as wearing clothing of some sort, rather than appearing naked. Nickell and other sceptics seem to find this a problem. But even if ghosts are real they are not physically present, i.e. they can not be captured and studied by experts like some rare animal. Thus they must manifest themselves by directly influencing the minds of the percipients. As Nickell obviously does not for a moment consider that ghosts might be real this is also no problem. The point is that this sort of speculation is hardly scientific.
Where his approach looks like becoming scientific, again he disappoints technically minded readers. He devotes a short chapter to Michael Persinger's studies of the alleged influences of electromagnetic stimulation and is unconvinced, like most others who have examined Persinger's work. However, he does not consider more likely physical causes of ghostly experiences associated with particular places, such as the effects of sharp variations in temperature in different parts of a building, or the effects of low-frequency sound caused by wind blowing through an open window, of which the subject is not consciously aware, although it is registered by the brain and produces feelings of unease.
Accounts of travels to supposedly haunted places become somewhat repetitious, especially as Nickell has obviously long ago decided there is nothing in them to seriously interest anyone but psychologists or folklorists, so one wonders why he bothers. He also devotes part of the book to the phenomena of the séance room, in which he describes how the mediums deceive their clients, or are sincere and also deceive themselves. There is also a chapter on poltergeists, and the inevitable collection of fake photographs.
The book could have been more interesting if it were not so wide-ranging, but confined itself to in-depth studies of a few of the more complex and interesting cases. Short summaries of ghost stories, whether folklore or allegedly real events, tend to be very similar. Also, a book with Science in the title entitles the reader to expect more technical detail. -- John Harney