One of my very favorite science-fiction novels when I was in university, I decided to re-read it and see if it still held up.
I have to say, for being written in 1935, it does not feel old at all and language wise is modern. There were few hints that it was written over seventy years ago.
All the things that I remembered from way back were still there and as intriguing as ever. I loved it as much as I did the last time I read it.
The only thing I noticed, and I know I'll forget it like I did last time, were the two or three places where the author indulged and went into details of his own philosophy on politics, psychology, religion etc. The author used the main character, a more evolved human, as the speaker, going on about how wrong various sectors of society were about their position. I forgive him, Olaf Stapledon was a philosopher and had a position. It didn't hurt the novel much at all.
Simple, classic science-fiction executed to perfection. A great novel.