In his novel Araminta Station, Jack Vance wrote about a future "Monomantic Rebellion" that led to attempts to genetically engineer humans so as to reduce sexual dimorphism. Vance imagined a society (populated by a people known as Zubenites) in which human embryos were cultured in artificial "tubs", "liberating" women from having to go through pregnancy. Vance imagined that a kind of "Monomantic Creed" was developed to indoctrinate Zubenites into a philosophy that vilified "duality" (normal human sexual reproduction). However, the Zubenites became difficult to replace, and with each passing generation, Zubenites germ cells became increasingly hard to coax into producing new embryos.
In my thinking about The Start of Eternity I have been influenced by Vance's idea of Monomantics. When Asimov wrote The End of Eternity he described how humans of the far future (more than 10,000,000 years in our future) gradually died off and the human species became extinct. Asimov provided no details about the extinction of humans, but a key character in the story, Noÿs Lambent, was from a time more than 10 million years in our future. Asimov did describe a slow evolution and a small amount of genetic change in humans through the next several million years. Asimov wrote that Eternity created a stable environment for humans and greatly slowed the pace of human evolution. I have been trying to imagine exactly how Noÿs Lambent was different from us, we humans of the Primitive.
Asimov invented the idea of "Hidden Centuries", a period of time lasting millions of years, including several million years leading up to the extinction of humans. Asimov provided us with little information about the "Hidden Centuries", but Noÿs Lambent was born in the middle of that hidden epoch. I am now imagining that Noÿs came from a society that included few males and where reproduction was achieved by artificial means. This is a twist that plays off of Asimov's depiction of Eternity as having a male-dominated culture and the way Asimov showed Noÿs to be a "liberated" woman.
There needs to have been a decision by the robots who created Eternity to establish the Hidden Centuries as a time period when human variants and alternative forms of human culture could be tested for their long-term survivability. Having looked into the future (and seen the extinction of the human species), the robots needed to find some stable form of human that would not become extinct. However, after studying many human variants, the robots finally decide that the fundamental underlying problem is their own decision to keep humans penned up on Earth. The robots learn that it is impossible for humanity to indefinitely sustain itself on Earth. The robots decide that, in order for humans to not become extinct, they must allow humans to explore outer space. This is a major problem for the robots because of the Zeroth Law, which requires the robots to protect humanity and human interests. The problem for robots is if humans spread to millions of worlds, then how can a robot recognize what constitutes humanity and the best interests of humanity? The robots ultimately devise a strategy by which humanity will spread between the stars and create Galaxia, a telepathically-linked group mind that spans the entire galaxy. The robots feel confident that a unified Galaxia will allow them to understand humanity as a vast galaxy-wide but unified super-organism, humanity will be an understandable "entity" that the robots can continue to protect according to the Zeroth Law.
The Start of Eternity will therefor provide two possible "visions of humanity's future". The first "vision" of humanity's future, Noÿs Lambent, is a woman from the far future, a future where the human species became extinct. Second, the inter-galactic civilization of the Huaoshy will provide examples, in the form of other human-like species, of how the humans might evolve in the far future if humanity is integrated into Huaoshy culture. The telepathic robots that control humanity's fate according to the dictates of the Zeroth Law will struggle to keep keep up their efforts to protect humanity, but ultimately they fail.