We live in an absurd universe. And once you throw in stuff like time travel, fiction can get even sillier than real life. But how can you write speculative fiction that lives up to our ridiculous world, without being dumb?
Some of the greatest science fiction/fantasy writers are extremely silly — Douglas Adams is the gold standard, but there are a number of others. And when you look around and realize that not too long ago, we were choosing between Sarah Palin and Joe Biden, two undeniably silly people, to be a heartbeat away from the American presidency, it's hard not to feel as though silliness is the new realism.
Like you just know that if you ever actually got eternal youth, it would consist of being stuck in a time loop where you're going to the bathroom over and over again. Or if aliens showed up, they'd only be interested in the music of Miley Cyrus and the performance art of Andrew Dice Clay. We live in a cruel cosmos.
And yet. Only a tiny minority of published speculative fiction is actually silly, and when you read interviews with editors, you frequently see them saying things like, "I'd like to see more humor, but it's seldom done well." Assume that outright silliness is just a subset of "humor" as a category, and you start to get a sense that science fiction and fantasy are facing an existential crisis of silliness. It is the crisis of infinite sensibleness. As rare as everybody says the Sense of Wonder is, a sense of the utterly ludicrous is even rarer.
One wonders how this could be true, when the leading lights of the global economy sound more like they wandered out of a Stanislaw Lem novel every day. You could plunk Ben Bernanke and Timothy Geithner down at the World Futurological Congress, and he would feel right at home.
So how do you write silly science fiction without sliding over the edge into nonsense or worse? It's a definite challenge. For one thing, humor is a distancing technique, which can have the effect of putting people outside of the story. Science fiction, meanwhile, already has a higher barrier of entry, for a lot of people, than "realistic" fiction, which doesn't require you to buy into a world that's not entirely our everyday "consensual reality." (I put "consensual reality" in quotes, because to this day, nobody has ever asked for my consent.)
So too much distancing, and your story risks feeling as though the reader is viewing it through a telescope. And you have to hang on to some suspension of disbelief, or it's no longer fun on some level.
And it's also true that humor is subjective, like sexiness and terror, and you're not going to be able to make everybody laugh. There are always going to be people who think they're cleverer than you are, and some of them will be right.
But here are a few tips, based on my own feeble attempts to be silly:
* Keep a consistent tone, and ideally make it a tone of self-assured control over the material. A lot of attempts at zany weirdness can fall into the trap of sounding as if you're trying too hard to be zany. The aura of desperation is lethal to the silly fabulist. (I've fallen into this hole many times, and have only managed to lurch out of it by using post-modern literary sentence fragments, in list format, as a kind of ragged step-ladder. Like so: "1. Ralph Waldo Emerson's enamel bone-saw fetish. 2. Mandible jazz. 3. Zen able-ism. 4. I'm so sorry for all of this.") You want a tone that says "I, the author, am a trained professional, and any resemblance between my loopy ramblings and the babbling of your five-year-old after chugging a two-liter Coke is entirely your five-year-old's fault." How do you do this? Try reading your shit out loud — to an audience is better, but to yourself is okay too. Even more than other stuff, the goodness of anarchic prose will show through in a live reading. Think of it as stand-up comedy and cut the weak jokes — and, to the extent that this isn't just pure comedy, try to have some kind of logical flow to it. There should still be a story buried under all these gems of the ridiculous. Speaking of which...
* Silliness often works best in contrast to something. If you think about it, many of genre fiction's most demented classics put something at least fairly sensible alongside their most off-kilter elements. In the case of The Hitchhiker's Guide To The Galaxy, Arthur Dent is very deliberately set up as a kind of "everyman" who stays resolutely ordinary in the face of a deepening weirdness. In the case of Harry Harrison's Stainless Steel Rat books, "Slippery" Jim DiGriz is often the most nonsensical thing in his world, a kind of trickster who dances circles around the unimaginative people he meets. It's very, very difficult to do a silly protagonist in a silly world. I've tried it, and it hasn't turned out well. You're quite probably a better writer than I am — especially since I traded a big chunk of my temporal lobe for a sex dreidl that doesn't even spin on a non-flat surface — but you may be hard-put to do the "silly person in silly world" bit. Likewise, you need to let people breathe a bit every now and then, and throw in some stuff that adheres to logic, or at least brushes against logic.
* Watch the authorial intrusions. Douglas Adams is god. And being god, he's able to manage an omniscient narrator that sticks in tons of snark and goofy asides and weird observations, without his readers/worshipers rebelling. But even Adams uses the device of the Guide to couch a lot of his narrative intrusions. If you have a third-person narrator, and it's just you, as the author, butting into the story with wacky observations and especially authorial opinions, then a little bit probably goes a long way. The readers may be on board for your topsy-turvy world and your lunatic characters, but they may balk at having to spend a few hundred pages trapped with the wild-eyed author. Also, I think that this comes back to the "not seeming too desperate" thing. When the author, via the third-person narrator, starts trying too hard to convince me that she or he is a very funny person, I start to wonder if that's possibly not true. On the other hand, I think Christopher Moore and A. Lee Martinez sometimes manage to have zany third-person narrators that don't make me want to hurl things. So it is doable. (This is off the top of my head — I don't have either author's books at my fingertips.)
* If you're doing satire, know what you're satirizing. There's absolutely nothing wrong with barmy nonsense for the sake of barmy nonsense. There are fish-men impersonating the Village People and sporting huge mutton chop facial hair to cover their gills while they do a massive choreographed rendition of "Go West," just because it's a neat set piece. Great, rock on. But a lot of fictional logorrhea does have a satirical point to it, and there's nothing more deadly than not knowing what you're satirizing. You may hate bureaucrats, pushy customers, lazy retail workers, or whatever — just spend some time thinking through what/who you're actually wanting to flay. If you read the original Hitchhiker's Guide back-to-back with Eoin Colfer's Hitchhiker's book, And Another Thing, you'll notice a huge difference. The original book is full of spleen, and the Colfer book is spleen-free. Colfer doesn't really seem to have it in for anybody. He seems to quite like all of his fellow beings, which makes his mockery so good-natured, it's actually a bit bland.
* Watch the puns and other markers of "low" humor. This is perhaps where my inner snob comes out, but it really only takes one or two puns before I stop giving a storyteller the benefit of the doubt. This probably is a matter of personal preference, but it's why I've never been able to get with Piers Anthony. I can only deal with insanity when it feels as though the author is really trying, and puns feel too cheap. Also, here's a rule of thumb: If your character names and other proper nouns sound as though they could have come from an R-rated porno spoof on Skinemax, then your humor may go unappreciated. This especially goes for naming your starship captain Quirk or Spork or whatnot.
* The things that make the world nonsensical are often not outlandish at all. You can get as much silliness out of a scuffed bit of carpet as you can from a woman traveling back in time and marrying all of the Beatles, all four of whom turn out to be her grandfathers, thanks to compound sperm. (Although my story "Call me Yokolinda, Granddads!" will be in the September issue of Thrilling Tales of Incest, Plus Wonder, But Mostly Incest.) Seriously, I can still remember the day I realized how much comedy gold you can get out of a busted radiator. And sticking a petty bit of insanity into an otherwise serious situation can be funnier than the other way around. Picture Captain Harriman fighting off the Destructivator fleet, in a completely deadpan, life-or-death situation — except that the elastic on his regulation underwear has just given out, and they're bunching up inside his spacesuit. He's about to attempt a life-or-death maneuver, flying his ship right into the mouth of the Destructivators' blast cannon, when one side of these skivvies starts sliding down into one leg of his flight suit. For added weirdness, these undies could be from the brief period when they experimented with artificially intelligent elastic, for added comfort, the A.I. on the briefs' waistband could be trying to give Captain Harriman strategic advice. It doesn't seem too ridiculous, given all we know about the hubris of the garment industry, that we could be stuck with super-intelligent underwear at some point.
But yeah, as I said way back in item #1, there still has to be a story in there somewhere. The characters still have to feel like people, and there still has to be something for people to grab onto, or else you're left with a sort of free-floating lunacy that goes nowhere — good for sporadic bathroom reading, bad for any kind of sustained attention. And don't forget to have fun with it!