This is the psychological phenomenon that underlies dowsing, automatic writing, table tipping, and the Ouija board. Quite unconsciously, the participant is moving the hand enough to make the movement of the involved device occur, though he may attribute the motion to the divine or supernatural force in which he believes. In all these events, nothing in the way of information is revealed to the operator except what he already knows. The effect is very powerful with some personalities, and no amount of evidence will disabuse believers in the magical nature of the phenomenon.
For the Ouija board this can be shown by the fact that when the operator is properly blindfolded, only gibberish is produced.
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