Most dreams are stimulated from the blood into the nerves and the nerve-centers. And the heart is the transmission station. For the blood has a unity and a consciousness of its own. It has a deeper, elemental consciousness of the mechanical or material world. In the blood we have the body of our most elemental consciousness, our almost material consciousness. And during sleep this material consciousness transfers itself into the nerves and to the brain. The transfer in wakefulness results in a feeling of pain or discomfort — as when we have indigestion, which is pure blood-discomfort. But in sleep the transfer is made through the dream-images which are mechanical phenomena like mirages.

Nightmares which have purely mechanical images may terrify us, give us a great shock, but the shock does not enter our souls.