The Eides are images that are considered gifts of the gods. Eidetic imagery was studied in Germany in the '40's and was defined as vivid imagery. The current work of Dr. Akhter Ahsen defines it as an image that has a life of its own. Dick was very interested in Eidetic Psychology because he felt that an image, if it came to us and we concentrate on it, creates a body response and is an experience which can be a learning process.
The significant formula for eidetic imagery is : I ---> S ----> M
Where I = the image, S = the somatic response and M = meaning.
The order is very important.
Meaning is the least important of the three.
See: Dick's opening talk for a fuller explanation of Eidetic imagery.