The infodump, as Todd VanDerWerff points out, may well be the single generic feature shared by all flavors of science fiction:
You might find some infodumping in a Western or in a period piece, but for the most part, we know the rules those genres play by because those genres take place in our reality, just in the past . . . . To a large degree, the division between hard and soft [science fiction] often hinges on things like infodumps. The hard [science fiction] is often for the people who are really, really interested in the science part of the science fiction equation. The soft stuff skews more toward the fiction end of things and isn’t particularly concerned with plausibility much of the time.
This strikes me as wrong in one crucial respect: the infodumps about which people complain occur at the outset of a work. They're presented as the technological enablers of the narrative to follow. They are exposition before the fact—before readers have any emotional investment in the characters whose narratives are enabled by the infodumped technology. No surprise, then, that people whose primarily invest in character or narrative find the lengthy technological preambles of hard science fiction off-putting.
To label as infodump the exposition on the Battlestar Galactica episode "No Exit" is to be a little too literal. "No Exit" did "dump" quite a bit of "info" on its audience, but the information was not intended to make the narrative work, because it already does. You cannot have an infodump four seasons into a series: you can only have a revelation. The argument should be whether too much information was revealed too quickly, but what else were the characters meant to do? Naming an episode after Sartre's No Exit signals a forthcoming entrapment of the character's own devising. Their Hell will be the other people they're trapped with.
But that's not where I'm headed with this post. I think the thematic parallels with Sartre's play are important—certainly significant is the implication that this is a Hell of their own devising, one in which they remain not by force or compulsion, but through fear of the unknown. (That all the characters begin by talking about what happened on Earth, only to become increasingly occupied with their own infighting seems an important parallel, even if I am being a bit literal.) What I want to focus on the effect on a viewer when almost 70 hours of thin-streaming history are followed by one of torrential exposition.
On a certain type of reader/viewer, the result is little different than the cumulative effect reading Ulysses or Gravity's Rainbow or Infinite Jest; namely, this person feels like the night sky yearns to snap into constellations—he feels like the heavens look down on, disappointed, because some personal failing prevents him from discovering the order they contain. So what does this person do?
If he's reading Ulysses, he maps Joyce's universe onto the tram-lines of William Martin Murphy in order to demonstrate that
[Stephen's] attempts at upward mobility are futile, frustrated in large part by Murphy’s reluctance to lower the tramfare. However, were Murphy to lower the tramfare, the people riding the tramcars would no longer comprise a tram-riding elite, and Stephen’s desire to ride the tramlines might atrophy into little more than a timesaving utilitarian impulse. Understood in this manner, Stephen becomes a pathetic figure obsessed with belonging to a class he can only feign membership in on payday.
If he's watching Battlestar Galactica, he writes the following post.(x-posted.)