ljs (02/18/83)
The pendulum described in Jeff Mayhew's contribution (a small weight attached to a 10" string) is a common device which is often used to quickly develop or achieve a hypnotic state. Almost any book on hypnotism or auto-suggestion describes it and often other experiments are discussed. Try this one: Holding the string between thumb and forefinger, so that the weight acts as a pendulum, place your elbow on the table. Try to keep the weight still. Now, don't look at the pendulum, but concentrate on "yes." After a while, you will find that the pendulum is moving in some pattern: circular or back-and-forth. Do the same thing again, but this time concentrate on "no." The pendulum will move in another pattern. Most people doing this little experiment generate consistent patterns for "no" and "yes." These patterns may be different for different people. This is a variation of the "finger signal" technique of the hypnotist.