A glimpse into the invisible book then occurs:

The intelligent way to read SF is mentally to reconstruct the invisible book for yourself, as you go along -tohone your xenoscientific reflexes.

Then we'll try to unwrap some of the thinking behind it, the allusions, Clement's ' invisible book' that lies behind the scenes in all hard SF.

There are invisible books and books that scream when you open them, portfolios of potent potions and countless volumes about venomous beasts.

"There are many things that he'll always come to you for," Cassandra continued, still reading from her invisible book.