I'm with Gaiman on this. No author has any obligation, ethical or otherwise, to provide further books in a series to the readers unless those readers are paying hard cash upfront for the missing books.
And what on earth is is an 'aesthetic promise'?
>unless those readers are paying hard cash upfront for the missing books.
Back a few years ago plenty of people would have done this if it had been offered. Maybe that would've helped his writer's block.
from the phrase I would expect that "aesthetic promise" is similar to a monetary promise, except as applied to aesthetics instead of money. A promise that something will be given.
from reading the article "aesthetic promise" seems to be "that particular bit of aesthetic satisfaction that you counted on when starting out on the series", in other words, one of the aesthetic promises of a continuing series of books is that there is a conclusion, so you read one book and the next, expecting that at some point they will all be put together into a whole.
Rather like how readers of Dickens day started reading his serialized novels in their papers expecting that the novel would in fact have an ending.