I wouldn't have gotten nearly as much enjoyment out of the series (including the 2 sequels after the trilogy) if I hadn't read Asimov's Robot Series. I know that the whole "you don't get it because you haven't read these other books" thing is kind of cliché, but I really do think that the majority of the joy I got from Foundation was because of how it connected with the Robot Series. But of course, part of the enjoyment should come from the book itself. I'd say that the book does get better as new threats to the Foundation appear, but the premise largely stays the same throughout the trilogy: will the Seldon Plan succeed? (NOTE) The reading sequence for me went something like: 1. Caves of Steel 2. Naked Sun 3. I, Robot 4. Robots of Dawn 5. Foundation Trilogy EDIT: remove redundant last paragraph
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