(Minor spoilers for Too Like the Lightning. They're so minor I'm not even doing a soft break here.)
I'm listening to Too Like the Lightning on Audible (which audiobook I strongly recommend) and there's something interesting about how it uses disagreements. They seem to work as prompts to the reader. I don't think it's unique for disagreements to function that way in a story, but this story does have unusually interesting disagreements. I see two broad categories of disagreements so far: Narrator vs. imagined audience, and character vs. character.
The first and most obvious disagreements are between the narrator and the audience he imagines will read his story. Palmer frames the story from the perspective of Mycroft Canner, who is writing an account after the fact of some events he was involved in. Canner is writing for an audience he imagines will be his contemporaries in the 2500s (if I recall the timeline correctly) or people even later in history—in any event, an audience with very different beliefs and norms from 21st century people.
From the very start, Mycroft insists on things he expects will be disagreeable to the reader. The story is written in an 18th century style (if I recall the century correctly), unfamiliar to his intended 26th century audience as much as to most of us in the 21st century. He insists on a few other presentation choices, too, some of which make the story more agreeable to us rather than less—but in justifying their use to an audience that would disagree with said choices, the disagreement actually functions as a prompt.
Mycroft chooses for example to use gendered pronouns. They aren't common in his time, and carry with them a stronger sexual charge. He supposes that the reader is going to picture the characters naked every time they read "he" or "she." Mycroft compares this—respectfully rather than disparagingly?—to displays of ankles in say Victorian England. He insists on using these pronouns anyway, arguing (roughly) that they come from those times when sex was on everyone's mind all the time—in a way that exposes the sexual undertones in the story. The choice itself works out well for many of us, but this disagreement does something interesting. It turns what would have been an invisible, unobjectionable choice to do the Standard Thing into a prod: Is that true for us in the 21st century? Is "supporting sex-think" an important function of gendered language? The frame is disarmingly silly, written in this exaggerated 18th century style, but there's a real question there to leave simmering in the back of your mind as you continue through the story.
There are others, too. For example, Mycroft insists on calling Bridger's abilities "a miracle," which is disagreeable to his audience and also uncomfortable for many of us in the 21st century. But besides narrator-audience disagreements, though, there are also character disagreements.
The one that sticks out to me is the disagreement between Carlyle Foster and Eureka Weeksbooth about set-sets. Set-sets are people trained from birth to work with radical body-computer interfaces. Eureka is a set-set—a Cartesian one—and has strange little interface pads all over her body—and when I write all over, I mean all over. All those interfaces serve to allow her to process and respond to an enormous amount and breadth of data—800 million mukta (?) passengers worth of data across 30 different variables—in real time, all day long. They're equipped with these interfaces early in childhood and spend all their hours training. Their only interface with other people is text communication. They only ever know their 'ba-siblings' by text. They have no normal human sensory experience—the interfaces on their body take over every sense, even pain, to process more data, longer, and faster. It's not just her skin—Eureka's eyes are covered, too. The interface uses smell and taste, too, so there must be interfaces in her nose and mouth also. Eureka first saw the sun when she was 17, and that's normal for set-sets. She can't even describe to Carlyle what her sensory experience within the interfaces is like. There's an enormous gap between Eureka and "ordinary humans."
Carlyle and Eureka disagree whether raising children as set-sets is okay. Carlyle Foster is horrified, having had a childhood more similar to ours. Carlyle was raised in the "real world," playing with other children. The idea of raising a child in the dark, never to see a friend or a sibling or even the sun until they are an adult, all so that they can be used as a computer, is grisly. It's a huge cost.
But the practice of training set-sets comes with a numerically huge benefit, Eureka argues. There was a system for managing the muktas before Cartesian set-sets came along, but it couldn't run the muktas as quickly or as safely. With Eureka, they're running the muktas at over 1,100 miles per hour instead of 900 (if I recall correctly—I probably have the units wrong) and something like a tenth the accidents.
It's still horrifying. But it makes a certain kind of sense. Eureka's defense of the practice and her reasoning makes her an interesting character. She has a sense of dignity and respect in her vocation as a Cartesian set-set. The disagreement prompts us: This is fucking weird, right? It's creepy, right? It's deranged, isn't it? Is this okay? Could this ever be worth it? The book hasn't answered yet, and I don't think it will, but it's another interesting question to keep simmering.
These disagreements in Too Like the Lightning seem to function as prompts for the reader: What do you think? They're pretty good, provocative prompts.