According to Seth, those CUs that would eventually become human consciousness as we know it existed during pre-history in a kind of pseudo-form which Seth called a dream body. The dream body, in turn, operated in what might be best thought of as a dream world, also formed by consciousness.
Seth called these pre-humans “Sleepwalkers” and their main concentration was still in the dream world, even though they were beginning to experiment with physical reality. The Sleepwalkers had bodies, some of which looked like ours, but they operated perfectly and effortlessly, were not diseased or defective in any way, and had some abilities that surpassed ours.
This state was one in which pre-humans could try out different ideas, create environments, interact with various species, and learn how they would work together. If things didn’t go the way they planned, they could try something else, without the physical consequences.
The Sleepwalkers did not age anywhere near as quickly as we do and did not need to procreate; gender was not important and these beings had what we would call both male and female qualities. In Seth’s recounting,
While men [and women] had their dream bodies alone they enjoyed a remarkable freedom . . . for their bodies did not have to be fed or clothed. They did not have to operate under the laws of gravity . . . They did not yet identify themselves to any great degree as being themselves separate from either the environment or other creatures. (Dreams, ‘Evolution,’ and Value Fulfillment, Volume 2, p. 222)
During the time of the Sleepwalkers, matter was impermanent; Seth said it pulsed in and out of existence. “What you really had in the beginning were images without form, slowly adopting form, blinking on and off, then stabilizing into forms that were as yet not completely physical. These then took on all of the characteristics that you now consider formed physical matter.” (Dreams, “Evolution,” and Value Fulfillment, Volume 1, p. 179)