It's worth mentioning that
The Star Fraction was Ken's first novel, where as
Learning the World is a lot more recent, with a far smoother narrative flow, whilst
Star Fraction is much edgier and angrier.
Just as an aside, Ken might never have got around to committing
The Star Fraction or anything else to paper, if one of his closest friend's hadn't grown so tired of him talking about his ideas that he almost bullied him into writing them down.
The friend's name? Iain M. Banks.
Fortunately, we've got them both as GofH's at a little convention I'm helping to organise next year, which should be a lot of fun!