The whole doctrine of these apparitions of the living, or, as they are called in Cumberland, _swarths_, and premonitions of coming events, proceeds on the supposition that people have a counterpart or other self, an _alter ego_, which goes about unknown to themselves, with their voices, features, form, and dress, even to their shoes, and is visible to those who have the unhappy gift of the second sight. This phantasm, or other self, is not the life or the spirit of the person whom it represents. He has nothing to do with it; he may, at the time it is seen, be sunk in unconscious sleep, or his attention and wishes may be otherwise taken up, and death may not be at all in his thoughts. At the same time, it is not without some connection with him. Strongly wishing is apt to make one’s _tàradh_ be heard at the place where he wishes to be, and if the person whose spectre is seen be spoken to the apparition disappears; but in general the _taibhs_ is independent of all thought, or action, or emotion of the person whom it represents. The doctrine does not assert that all men have got such a double, much less that those who are most largely gifted with the second sight see it always, or even frequently. The spectres are visible to the seer only under exceptional circumstances, in certain situations, and at certain times. The most usual of these are after dusk and across a fire, when a sudden or violent death has occurred, or is to occur, when a friend is ill, when strangers are to come, or any event is impending calculated to make a deep impression on the mind. Spectres are often seen with as much distinctness as external objects, and it would be a great injustice to the poor man, who claims to have visions of things that are not there at all, to say he is telling an untruth. To him the vision is really there, and it is but natural for him to think it has an existence separate from himself, instead of referring it to an abnormal state of his mind and nervous system. Some spectres “move with the moving eye,” being what the poet calls “hard mechanic ghosts”; others have their own proper motion, and probably arise in the brain. The former are the most common, and it was a test among _taïshers_, whether the figure seen was a wraith or not, to stoop down and raise themselves up again suddenly. If the figure did the same, it was an apparition, a _tamhasg_.