You know, I hit a point somewhere in high school where I stopped reading Asimov's because I'd developed a great dread of encountering yet another Civil War alternate history. I have no idea, looking back, if they were actually publishing that many of them, but whatever my breaking point was, they passed it.

Excellent post! I particularly like the Chandler line—if I were John M. Ford, I would write a brilliant parody of "On First Looking into Chapman's Homer" about Chandler and Hammett and Christie. "Or like stout Chandler, when with private eyes / He read of that black falcon..."

I look forward to reading your "Five Irrational Histories"—I've started reading the new Rabid Transit but haven't gotten to your story yet.

'sfunny, when I think of AH, I think of Leinster's "Sidewise in Time" (which I'm not sure I ever read) and all its myriad descendents in the '30s through the '60s—I must have read dozens of such stories as a kid, though I'm having a hard time coming up with any specifics other than Man in the High Castle. (I'm pretty sure I read all the stories in Sandra Ley's 1976 anthology Beyond Time, but on looking at the TOC I don't actually remember any of them.) Silverberg's "Lion Time in Timbuctoo" was what first opened my eyes to possibilities outside what I was used to in AH: rather than include the obligatory scene in which people speculate on how things would've been different if only things had gone the way they did in real life, Silverberg simply included a brief introduction explaining what the POD was. I was amazed—"You can do that?"

It took me a long time, somehow, to figure out that a large percentage of Waldrop's stories are AH. (And speaking of Waldrop, I feel obliged to link to his comprehensive discussion of Hitler Wins stories at Infinite Matrix—I know you've seen it, David, but some others might not've.) He doesn't necessarily play by the rules either; look at "Us" (a set of alternate Lindbergh Kidnapping histories). One could do worse than aspiring to follow in Howard's footsteps.

And as I noted a couple months ago, Robert Reed has been breaking the AH rules in a different sort of way, both by going way far back for his PODs, and by allowing a lot of things to stay the same despite phenomenally huge PODs.

Anyway, what I'm really getting at is that I've barely read any of the AH stuff that's been published in the last ten years, when there's been a big resurgence of it. I haven't read the Alternate Resnicks anthologies, or much of anything by Turtledove, or Stirling's recent work. So my abiding fondness for AH (and something definitely appeals to me about the Single Point Of Divergence and the Meticulously Logically Worked Out Subsequent History, though the military details rarely appeal to me much) may not have anything to do with what most people are talking about these days when they refer to AH. I should keep reminding myself of that.

I might have to give Reed a try. One of the things I realized while writing “5IH” was, since you’re already messing with the impossible in an AH story, nobody really has a right to complain about the merely improbable. So if I want to completely screw up the history of Eurasia starting in the fourth century B.C. and yet still have Oscar Wilde and Bosie Douglas shacking up in a recognizable London twenty-two hundred years later, that’s my business.

It took me some time, but I eventually realized I can do anything I want in a Thompson Tang Gao story (for the world, you see, is irrational). There's an internal logic that must be maintained, but beyond that, the sky's the limit! (I find it a bit daunting, to tell the truth).

[plug]Hey, there's a TTG story in here: http://www.fictionwise.com/ebooks/eBook22723.htm[/plug]

I am in the funny position of being someone who hates it when, in Alternate History, painters named da Vinci show up in the Renaissance despite a Roman-era POD... and who has just written a story filled with such (and thanks for buying it, David).

But the point of that Zeppelin story is to be alternate historiography. Whether or not you believe Leonardo da Vinci can show up if Hannibal won, says a lot about what you believe about how the world works.

And whether or not you (or your story) cares if it could happen says something about what itches your story is trying to scratch.

If a story plays with causality willy-nilly -- that is, without any purpose in doing so -- that's fine, but it becomes much more art-as-object then, more distancing; like much metafiction and slipstream, it's a story about the story that it is, rather than about the world.

If a story wants to do without POD-and-extrapolation and still aspire to be more than "just fucking around" (not that there's anything wrong with that), it is -- explicitly or implicitly -- proposing or searching for an alternate model of history and causality.

The "this could have happened" frisson of Hard AH, like the "this could happen" frisson of harder SF, is something that I like. Not the only thing I want in my diet, though. I find the search for another way history could work, if undertaken with some rigor, if anything more interesting. (And I also like "just fucking around").

I think there are a lot of models for AH beyond POD-and-extrapolation. Each model implies a worldview, though, and it bears thinking about, what worldview the way the story works implies.

I think it’s because I have such a Newtonian, mechanistic view of history that I have no trouble with “shadow histories”. Without believing in chance (except as a shorthand for unpredictability), I can’t really buy into the idea of a single Point Of Departure — because then I have to ask why things happened differently, which implies an earlier POD, and an earlier one, all the way back to the First Cause.

And if even a single change implies an infinite number of other changes, it doesn’t really seem to matter how unlikely some of the changes are.

As an SF writer, though, it’s convenient to be able to make the distinction. :)

The motivator behind “Five Irrational Histories” was the idea that some alternate histories are “rational” — derivable, in some sense, from the history of the timeline we live in; the rational histories and ours are branches off the same tree, whereas the “irrational” histories and ours, no matter how close they may appear at first, in fact do not touch at any point . . . and so can be as odd and unlikely as I like.