The immense difference between the effect of abstract concepts and that of imaginative knowledge is easiest to see in an incident where the effect was painful in nature: A man was present when his brother had a leg amputated. As the bone was cut it made a strange sound; at that moment the man felt a fierce pain in his leg at the place corresponding to where his brother’s Operation was taking place. For a long time he could not rid himself of the pain, even when his brother no longer felt any. The sound emitted from the bone had, through the Power of imagination, impressed itself deeply into the man’s ether body and produced the pain.
A physician in Bern once made an interesting experiment. He took an ordinary horseshoe and connected to it two wires of the type used in electrical machinery. Everyone thought the gadget must be electrified, and those who touched it were certain they felt an electric current; there were even some who were convinced they experienced a violent shock. All these effects were produced simply by what the persons concerned imagined to themselves; no remonstration convinced them otherwise. People became rich by manufacturing pills from ordinary bread. The pills were supposed to cure all kinds of illnesses, but were especially popular for curing sleeplessness. A lady, a patient in a sanatorium, took such a pill regularly every evening and enjoyed sound sleep. One night she decided to take her own life and swallowed as many of these pills as she could lay her hands on. It was discovered, and the doctors were greatly alarmed; she showed all the signs of someone dying. One doctor remained calm, the one who had manufactured the pills.
Source: Rudolf Steiner – GA 55 – Supersensible Knowledge: Lecture IX: Wisdom and Health – Berlin, 14th February 1907