This kind of comment is what keeps me coming back to Hacker News. I didn't know that Lemaître had proposed that the expansion was accelerating -- actually, I didn't know much about Lemaître at all, truth be told. ( The Day Without Yesterday just went on my reading list -- thanks!). In any case, I guess Stapledon must have been working off of Lemaître's model, rather than cooking up something unique.
Still, like you, I do like to imagine that Stapledon tapped into something that was somehow beyond the ordinary. I don't feel like speculating beyond that, but however he did it, Star Maker is an extraordinary book.
As a humble scientist Lemaître didn't take the credit of the discovery of the expanding universe. Appearently there was a nice presentation by experimental particle astrophysicist Ariel Goobar at "Symposium - Georges Lemaître’s Big Bang In Modern Cosmology: A Celebration" last month:
https://fys.kuleuven.be/ster/meetings/lemaitre/programme
At the end it states:
"SNIa cosmology provides stunning confirmation of cosmic expansion – as predicted by Lemaitre in 1927!
• Expansion currently accelerating – as proposed early on by Lemaitre to explain the age of the Universe
• Is it Einstein’s CC or some exotic new phenomena? Observers busy trying to find out. Theory badly needed!"
Still, like you, I do like to imagine that Stapledon tapped into something that was somehow beyond the ordinary. I don't feel like speculating beyond that, but however he did it, Star Maker is an extraordinary book.