It is plain that your friend swings the weight himself, but he is unaware of two factors: He knows nothing of his own muscular action and nothing of his own mental processes which have produced that action; hence this experiment must be placed among the automatisms like table-turning and water-divining. One is prepared to find that the trick has its place among the mechanical adjuncts of spiritualism: it was used in ancient times as a means of divination, and is used by mediums of to-day when they tap out spirit revelations with a gold ring suspended in a glass tumbler.
If intelligent people like your friends can be made to believe that the weight is moved by some extraneous force, it can be understood that the trained medium, full of a belief in the supernatural, finds it an easy task to let the unconscious have possession of his or her muscular actions and spell out memories and fantasies which one is asked to accept as evidence of spirit control.
Planchette (described in Chapter IV) finds a place in the family circle, sometimes with the result that a single hit becomes a tradition after all the other stuff has faded from memory. A friend, who told me that he saw Planchette predict truly the month in which the Boer War ended, admitted that his family had toyed with the instrument night after night, but he failed to remember any other results. I must add that he never believed in the thing, but, nevertheless, the one lucky shot was remembered.
Table-turning is another half-way house between the parlour trick and the full-blown occult. Several people sit round a light table with their hands placed upon it, and, after due ‘concentration of mind’, aided often by a dim light, the table begins to move and the spirits are at work. Then a sort of Morse code is invented to communicate with the spirit entities, and the revelations begin.
Here I will quote from page 219 of _Raymond_, that widely-circulated book by Sir Oliver Lodge:–
‘During the half-hour … I had felt every now and then a curious tingling in my hands and fingers, and then a much stronger drawing sort of feeling through my hands and arms, which caused the table to have a strange intermittent trembling sort of feeling, though it was not a movement of the _whole_ table…. Nearly every time I felt these queer movements Lady Lodge asked, “Did you move, Woodie?” … Lady Lodge said it must be due to nerves or muscles, or something of the sort.’
Compare this with the feelings of the water-diviner (Chapter V):–
‘The muscles of the arm become contracted when the bodily magnetism is affected by the presence of water…. I suppose it must have something to do with the composition of the blood and nerve cells.’
Or with those of a hysteric who, previously relieved from mutism, was again struck dumb during a thunderstorm: … ‘I felt the electricity passing all over my body; it made all my muscles quiver and then went out at my finger-tips.’
No one can deny the reality of these feelings, as feelings, but in the first instance they are due to spirits, and in the next to water, and only in the case of the man known to be sick in mind is the real explanation likely to be accepted by the subject. They are all products of imagination, suggestion, self-deceit, or dissociation–call it what you please if you understand that the feelings have their origin in the mind of the subject and are not due to any external cause.
But in the first two examples they are associated with muscular movements which, we must believe, are carried out unknown to the doers and hence have their source in a dissociated stream. As usual, once the dissociation is established, there is no limit to its manifestations. Picture three or four Dissociates at work at a table, all bent upon producing signs of the marvellous, all blind to the mechanism at work, and with the hypersensitiveness of the dissociated stream ready to draw on the memories of the unconscious.
Mixed with this is the possibility of more elaborate deceit: when the hands of all are raised from the table their knees may still be under it; and if the knees are clear of it a blackened lath concealed up a sleeve can still work miracles.
This is taking us beyond the purely domestic, but there is no difference between the after-dinner tilting of the table for amusement and the same thing done at a séance–the mechanism is the same, but one is treated as a jest whilst the other is something worse. We see again the typical series with simple trickery at one end and reason-destroying dissociation at the other.