As for whether it is real or not, I can only say that I believe it is. Everyone must answer this for themselves but for me the testimony of people like my grandmother and Ms. Shaw is convincing. On the other hand, I am sure that Carl Sagan would have no trouble lumping such reports in with those of sightings of aliens, ghosts and the Virgin Mary – all the sort of thing that good, intelligent people have sworn to and yet reliable evidence to support them is lacking and actual frauds are not uncommon.

A glance at the entry for "clairvoyance or second sight" in the skeptic's dictionary (SkepDic.com) rightly points out the appalling record of professional clairvoyants whose record of fraud is a lot better than their record of accurate prediction. "Real" second sight does not appear to be something that one can call upon at will or on presentation of a fee. Nevertheless, this essay will proceed from the assumption that there is a real second sight.

Does it occur only in the islands? It depends who you believe. Some may know the interesting story of Dr. Judith Orloff, a psychiatrist whose book "Second Sight" was published by Warner Books in 1997. The daughter of two medical doctors in California, and now herself a professor at UCLA, Orloff has begun to incorporate her "psychic gifts" into her practice ever since she made the mistake of ignoring a premonition of a client's suicide attempt.

Nevertheless the idea of second sight does not enjoy much currency or respectability outside the islands. Conceivably there are potentially credible people in the modern world who are told by their parents, as Dr. Orloff was, to keep such things to themselves lest people think they were strange. One is reminded of the unfortunate Cassandra in Greek mythology, who was condemned only to make accurate and doleful predictions that nobody would believe. It is easier and less embarrassing just to keep quiet and ignore whatever promptings there may be, perhaps until they go away altogether. This is hardly something you'd want to talk about to strangers.

Why, then, would it occur disproportionately among the Scottish islanders? Either one must posit the existence of some genetically transmitted abnormality, or say that, while the potential exists in people all over the world, the islanders are more culturally susceptible: that is, they are better prepared by their cultural environment to recognize and embrace the phenomenon. One is certainly more likely to admit to something like this if one is likely to be believed rather than treated like a lunatic. This might also explain why the faculty does not seem to have traveled with the emigrant population to Canada and New Zealand, as far as I know.

If we buy into the notion of second sight, at least in its Hebridean manifestations, are we therefore implicated in the rest of the islanders' cultural, quasi-medical and spiritual assumptions? Absolutely not. The popular religion which was passed on from the time of those early Irish saints to our immediate ancestors had other features we may find a great deal more awkward than the second sight. The Carmina Gadelica collected by Alexander Carmichael in the Western Isles in the late 19th century contain many loricae (breastplate songs) and caims (encompassing chants), which find their way into faddish modern anthologies, but which presuppose a spirit worldview few would recognize as authentically Christian. And they themselves are the tip of an iceberg made up of eolas, (that is, charms for warding off the evil eye and various other kinds of ailment), and a mixed bag of pagan rites and stories about fairies, bogles and water-horses.

So intricately are these various features combined in the imaginations of the islanders that it is easy to react the way the Reformation ministers did and blast the lot of them, blast the whole religion as so much superstition. The ministers were so determined to root out all this nonsense, that they even tried to stamp out the language in which this spirit worldview was communicated. They almost succeeded too. My grandfather, whose favourite uncle was said to sit and converse with the fairies, never even passed the language he loved on to his own sons. Allison, the minister's daughter, would probably not have approved. The danger of this extreme approach, however, is that you throw the precious babe out with the bathwater.

Meet the author, Andrew Morrison