Hypnotists use the power of the mind over the body in order to exert their influence. The hypnotist must only convince the patient that something is true, and the patient will act accordingly. If he convinces the patient that his arms are as heavy as lead, then the patient will be unable to lift his arms. If he convinces the patient that a piece of ice is a red hot poker and he then touches the patient’s skin with the ice, a blister will develop. The body will react to the suggestion and not to the reality, and signs of a genuine burn will appear.