There're right ways and wrong ways to write a philosophical tome disguised as a novel. Nobody comes away from, say, Atlas Shrugged thinking "What a great action romance novel, and oh how subtly did she slip her message into the plot!" Instead it feels like you've just been harangued by ol' Strident Ayn for what feels like two thousand pages (which is nonsense, since the Kindle edition is only 1188.)
Meanwhile, ask someone about Starship Troopers and they'll be like "Oh, that Military SciFi novel?" without it crossing their minds that the majority of the book took place in classrooms of one type or another.
Having just re-read 1984 as a followup to reading Julia*, I was struck how much closer Orwell's novel is to Heinlein than Rand in structure. It's tightly written and steps along pretty smartly and in retrospect it's hard to think that maybe as much as half of it takes place either as the main character reading a political treatise or getting interrogated by the Thought Police. (I don't mean to spoiler 1984 for you, there, but yeah, Winston does get busted by the Brain Fuzz and given a cerebral shampoo.)
*What was also neat was realizing how the author of Julia had picked up a few little details from the original book and spun them into much more significant plot points when seen through other characters' eyes. The scene in 1984 where Winston passes the site of a recent rocket bomb attack and kicks a severed hand off the sidewalk into the gutter takes on a whole new tone, for instance.
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