Marie Brennan's Blog, page 201
August 30, 2012
Guest Post: Morgan Keyes on herbal research (with bonus giveaway!)
Y'all may have noticed that I, er, do a lot of research. Like, a lot. So when Morgan Keyes (a friend and fellow writer) contacted me offering a guest post on the topic of how she researched herbal medicine for her upcoming middle grade book Darkbeast . . . I like to help friends, but the fact that I wanted to read her post may have also factored into me saying yes. :-)
For those who want more than just the research guts, Morgan will also be giving away a copy of Darkbeast to one commenter, chosen at random. You have until 11:59 EDT tonight to leave a comment here and thus be eligible. No login required; just sign your comment with some kind of identifier, so we can tell the anonymouses apart!
***
In Darkbeast, twelve-year-old Keara runs away from home rather than sacrifice Caw, the raven darkbeast that she has been bound to magically all her life. Pursued by Inquisitors who would punish her for heresy, Keara joins a performing troupe of Travelers and tries to find a safe haven for herself and her companion.
In the novel, Keara's mother is an accomplished herbalist who has vast stores of plant-based products that she uses to treat a wide variety of ailments. Keara has learned much at her mother's knee, both about collecting various rare herbs and about selling the same. As with much of the knowledge we absorb from the world around us, Keara doesn't realize how much she knows until she's called upon to use her specialized information.
If only I had Keara's information embedded in my own mind!
Instead, I needed to do a lot of research about herbs. I'm a trained researcher; I worked as a research librarian for nearly a dozen years before I started writing full time. For Darkbeast's herblore, though, I used a different research foundation, one built in my very first professional job, as a lawyer.
Years ago, I was a lawyer representing many clients who manufactured food and nutritional items. My goal was often to convince the Federal Food and Drug Administration that my clients' goods were "generally recognized as safe" (and therefore foods that could be marketed under a relatively relaxed food regimen, instead of the stricter controls for food additives, drugs, etc.) "Generally recognized as safe" could be proven in many ways, but one key option was showing that a plant had been consumed by humans for hundreds or thousands of years without any adverse effects.
As a result of the legal requirements, my office soon filled with a stunning array of cookbooks. I leveraged recipes, especially ones dating back a couple of centuries, to show that foods had been used for a long time, without anyone falling ill.
Of course, many of the foods I worked on had obscure ingredients – herbal non-nutritive sweeteners, for example. Those herbs weren't likely to be listed in early cookbooks. Instead, I frequently researched medical treatments (even if an herb didn't cure a disease, I could often cite it as a food reference.) I also read many anthropology studies that discussed ancient peoples' use of ceremonial foods or early methods of food preservation.
Over the years, I've forgotten many of the specific titles that I relied on regularly in my law practice. And over the years, huge new libraries of information have become available over the Internet.
Imagine my pleasure, when I first started to build Keara's stock of herbs, and a search of the phrase "medicinal herbs" yielded more than three million hits! I could readily limit the results by adding symptoms I wanted Keara and her mother to treat ("pleurisy", for example, or "mental fog"). I could cut through the list by adding traits of the plant when that mattered ("yellow flower" or "triple leaf"). I could sift the results by restricting environmental information ("swamp" or "snow pack").
And when the Internet didn't give me the right information, or it gave me too much information, there was always the library's grand collection of cookbooks (Dewey Decimal Number 641.5).
Of course, Darkbeast isn't a treatise on the actual use of herbs. In fact, the vast majority of the herbs in the book are completely made up. But my background as a food lawyer leavened by my research skills as a librarian helped to make every herb ring true.
If you're a writer, what's the most challenging background research you've ever done? If you're a reader, what fantasy novels have you read that were (or felt!) especially well-researched?
***
Morgan can be found online at her website or on Facebook.
Darkbeast is for sale in bricks-and-mortar and online bookstores, including: Amazon | B & N | Indiebound
Morgan Keyes grew up in California, Texas, Georgia, and Minnesota, accompanied by parents, a brother, a dog, and a cat. Also, there were books. Lots and lots of books. Morgan now lives near Washington, D.C. In between trips to the Natural History Museum and the National Gallery of Art, she reads, travels, reads, writes, reads, cooks, reads, wrestles with cats, and reads. Because there are still books. Lots and lots of books.
August 29, 2012
a couple of Kickstarters (or Indiegogo)
So, with that in mind, these three are all projects I actually have a personal desire to see succeed:
Pe' Sla: Help Save Lakota Sioux Sacred Land -- this one was launched when a sacred site in the Black Hills was put up on the auction block by the landowner. It's since been taken down from auction, but according to the updates, the Great Sioux Nation is in private negotiation to buy as much of the land as they can. This is a Flexible Funding campaign, which means they get the donated funds even if they don't reach their goal; it's also worth noting that the crowdfunding is in addition to the money being put up by the tribes themselves. So the project helps take some of the burden off them/expand how much they can purchase and protect. Given the history in this country of fucking over indigenous groups by taking their land, this is a nice, direct way to help do the right thing.
The Gamers: Hands of Fate -- on a less serious and political note . . . but only partly, I guess. I linked to this one before, but as part of a link dump, with very little explanation. To go into more detail: as described in this update, the filmmakers are actively concerned with and interested in doing something about the problems with gender in the gaming community. I quite enjoyed the first two movies in the series (the first on in particular is a hilarious tour through all kinds of good ol' bad tropes in D&D), so I'm hoping this one gets the last bit of funding it needs to happen.
Electric Velocipede -- finally, a small one for the magazine Electric Velocipede, which published my short story "Selection" some years back. They're a quirky little market, and about halfway to their goal, which will fund them for the next four issues (i.e. a year).
August 28, 2012
fun with wuxia
What are your favorite wuxia plot tropes?
I'm thinking specifically of the more mystical end of things -- more The Bride with White Hair than Hero, but really, anything in that general direction. I need to invent some history for this chapter, and I need some fuel to get my brain rolling in the right genre. (Feel free to recommend movies I might enjoy, while you're at it.)
August 27, 2012
(Re)Visiting the Wheel of Time: On Prophecy
I thought about waiting a while longer. See, the major example I want to use for illustration is a plot that hasn't actually paid off yet, as of the books I've read. This means that, while I can talk about where I think it's going to go, I don't actually know yet if I'm right. (Possibly some of you do, as I suspect the resolution is in The Towers of Midnight. But I dunno; maybe it's in A Memory of Light. If it's in ToM, though, don't give any spoilers in the comments. I want to find out on my own how much of this is accurate.) In some ways, though, I think it's more interesting to do it like this: to say what I think right now, without the hindsight warping it. So here we go.
The reason I wanted to discuss prophecy is that I think it's one of the things Jordan does really, really well. In fact, if there's one thing I would point at as the reason for my fannishness in high school -- the thing that made me engage so enthusiastically with this series -- prophecy would probably be it. On a metaphysical level, I'm not so fond of the trope: it puts the characters on a railroad track, taking away their agency and making their choices less meaningful. And that's kind of true here, too, though Jordan sometimes goes the additional step required to make that interesting, which is to have the characters grapple with what it means to have their actions predestined. On the whole, though, it isn't the existence of prophecy that I like.
It's the way Jordan handles it. He strikes, I think, a very good (and delicate) balance of foreshadowing, giving enough information to be interesting, not so much as to spoil the entire plot. More to the point, he does this the right way: not through vagueness (which is what way too many fantasy authors try), but through breaking the information up and scattering it in a dozen different places.
It isn't just the official Prophecies of the Dragon, with their pompous, pseudo-epic verse. It's Egwene's dreams, and those of the other Dreamers. It's Elaida's Foretellings, and Nicola's, and Gitara Moroso's. Min's viewings. Aelfinn and Eelfinn tricks. Aiel prophecies and Sea Folk prophecies and things that aren't even prophecy of any sort; they're just little details of culture and history, stray lines characters speak here and there, tiny pieces you have to glue together to see that they have any significance at all.
Sure, some of it is vague. (Hi, Karaethon Cycle; how ya doin'?) But some of it is very specific, very clear . . . so long as you put it together right. And that's why I think it works: if you're the sort of reader who doesn't want to know where the story is going, you don't have to. Just read along, notice the obvious stuff, and let the rest surprise you when it comes. If, however, you're the sort of person who likes to put together narrative jigsaw puzzles -- which I am -- then you can have a great deal of fun playing chase-the-clue through the books.
Having made the general statement, we'll now go behind the spoiler cut for a specific example to show what I mean.
So, Moiraine.
She "died" -- or rather, disappeared -- at the end of the fifth book, fighting Lanfear. (I had kind of a hilarious conversation with a friend when she hit that point in the series. We were in high school, and when she walked into English class the morning after she finished The Fires of Heaven, we had this exchange: "No way." "Of course not." "Good. I didn't think so." "Like he would really do that." "Okay." Utterly incomprehensible to everybody around us, but we both knew what we meant.)
It was obvious to us, even before we cracked Lord of Chaos, that Moiraine wasn't really dead. The interesting part wasn't the (total lack of) suspense about whether she was coming back. It was the jigsaw puzzle of how.
The answer, of course, is Mat. That became explicit in Knife of Dreams, six bloody books later. But if you wanted to look for it, you knew that way sooner -- and you know more than that, too.
There's no good, linear way for me to approach this, because the information isn't given in a linear fashion. It's a web, so I'm just going to wander through it.
The Aelfinn told Mat, in the beginning of The Shadow Rising (book 4), that he was destined to "give up half the light of the world to save the world." During The Eye of the World (book 1), Min saw an image around Mat, of an eye on a balance scale. Put that together with Mat's generalized Odin imagery and Egwene's book 5 dream of Mat dicing with his eyes hidden and blood running down his face, and it becomes clear that "half the light of the world" means one of his eyes. (Kind of a nice phrasing for it -- concrete but not instantly obvious.)
"To save the world" is less immediately concrete. A Crown of Swords (book 7) has Min thinking about how Rand is almost certainly doomed to fail at his task without the help of a woman who's dead. This person is, presumably, Moiraine. Good new for him: he isn't doomed! Rand needs Moraine to save the world; Mat will save Moiraine; he will give up one eye to do so. (We'll come back in a minute to the question of why we can be sure that's what Mat's prophecy refers to.)
Min also has a comment in ACoS about how she only ever had one viewing that didn't come true. Exceptions like that are suspicious; they make us wonder if they maybe aren't exceptions after all. She says outright that the viewing in question had to do with Moiraine, so clearly it will come true later, after Moiraine comes back. It could be the one that makes Min say Rand needs her to win, but I don't think it is; there's a line elsewhere in the series about how Min's viewings sometimes take the shape of "either/or," and they're always dire when they do. I suspect that particular viewing was of that sort. What else could it be?
Well, there's a bit in the beginning of The Shadow Rising where the girls are being girly, talking about boys, and Moiraine says -- kind of out of nowhere -- that she knows the face of the man she will marry better than any of them do. I'm not sure I buy that line, really; Nynaeve knows Lan's face pretty well by then. But it suggests Moiraine knows, prophetically. What would her source be? Unless her marriage is important enough to make it into one of the official prophecy texts (which I doubt), or somebody had a Foretelling (which I also doubt), it's probably one of Min's viewings. And that would be the one that hasn't come true.
So who's Moiraine going to marry, anyway? My guess is Thom Merrilin. It isn't Lan (unless Nynaeve's marriage is going to get a hell of a lot weirder), but it needs to be somebody Moiraine knows well. Thom is the most likely candidate, based on his known involvement in royal-level politics, aka the social circles Moiraine was born into. I don't remember anymore what hints indicate the two of them have a history, but I seem to recall that they do, and my money's on the two of them marrying.
Especially since Thom's going to be part of the rescue. We know that from the same dream that had Mat dicing with blood on his face: "while" that was happening (an important conjunction), Thom pulled Moiraine's blue crystal out of a fire. Pretty obvious rescue imagery, there. But there are more reasons than that to believe they'll both be involved. The Eelfinn, the fox-people, have Moiraine, and they're somehow akin to the Aelfinn, the snake-people. There's a children's game in Randland called Snakes and Foxes -- which, if I recall correctly, one can't win without cheating. (Certainly one can't win; I seem to remember Mat saying something about cheating.) Each game starts with a rhyme: "Courage to strengthen, fire to blind, music to dazzle, iron to bind." Any time one visits the *finn, they're asked whether they have brought with them sources of light, iron, or musical instruments. Thom, of course, is a gleeman -- Mr. Music himself.
I wonder, but don't know, whether there will be four people in the rescue party, to match the four things in the rhyme. (Or at least three, for the three things forbidden by treaty.) If Thom is music, Mat is . . . light? Courage? If others are going to be involved, Perrin is the next most likely candidate. He's obvious for iron, and besides, he's probably their way into the *finn realm. Mat's already been through both doorways, which means he can't go through them again. The only other known way in is through the Tower of Ghenjei, which exists in the real world -- and Mat may be on his way toward that -- but also in Tel'aran'rhiod, where, if memory serves, Perrin saw it in the wolf dream. (I actually can't remember where the hell either of them is right now, but I think they're both somewhere in the south-ish -- possibly not too far from Whitebridge and the physical tower.) The fourth . . . I want it to be Aludra for light, with Mat for courage, but I'd be surprised if it was. Possibly there will only be three, and Mat will be toting a firework. Or a cannon.
Regardless, they're going to cheat. They're going to bring the things they shouldn't, and Mat's luck will probably be involved (though the dream of him dicing might just indicate him taking a risk), and he'll lose an eye, but they'll come out the other side with Moiraine, and she will possibly marry Thom.
Some amount of this has been coming ever since book 1, when we saw that eye on a balance scale. Other bits probably got added along the way. But it's been coming for a long time, and it's been there for the readers to see -- but only if they did the work to see it all. If you didn't pay attention, all you would know is the broad outlines, not the details. And even with the details, we don't know everything. Why the eye? Why is that going to be a part of Moiraine's rescue? I don't know; but I'm eager to find out.
Apart from the textual fun of playing with this stuff -- seriously, I'm not kidding when I say that arguing this kind of thing on CompuServe's Wheel of Time forum is how I learned close reading, and to hell with my English classes -- it's kind of a neat trick to use when your readers are having to wait years between books. Just as the fans of Lost entertained themselves from episode to episode by trying to guess where the metaplot was going, Wheel of Time fans could (and did) spend endless amounts of time combing the books for hints about future plot. (What else could we do? If Jordan wouldn't deliver, we would, by way of endless speculation.)
I also think it helps the author have his cake and eat it, too, when it comes to the role this trope plays in fantasy. Yes, the path is laid out for Our Heroes, in a fashion compatible with the notion that they are all important enough to be Destined. But by fragmenting it and disguising it, he adds a layer of mystery that helps make their actions and choices seem less wholly pre-determined. And, as I said, Jordan at least sometimes goes the extra step of considering what that pre-determination means, at least from the perspective of the characters. Mat is told he's destined to marry the Daughter of the Nine Moons, and so the interesting part isn't the surprise that it happens, but rather the question of how he reacts when he meets her. Egwene gets hints from her dreams, and faces the choice of what to say and do as a result. Rand has known since the second book that he has to fight the Dark One, and he thinks he knows what the price of that will be . . . and so the driving issue for him has been what freedom he has within that constraint. Can he choose how that moment comes? Can he avoid dying? Can he make sure there will be something left that's worth preserving?
I'd like to read a fantasy series that hits those questions head-on. Like it or not, prophecy is part of the basic furniture of the fantasy genre, and for all its flaws we aren't just going to chuck it out the window. The interesting question, both inside of the story and out, is what you do with it.
August 26, 2012
Pieces for the Precious
There are two basic categories. The first is "Operation Remember How It Goes." Right now I'm working on pieces I used to have memorized, and can play in their entirety or very near to it . . . so long as I don't think about what I'm doing. The instant I pay attention to my fingers, fffffffffft. Goodbye. My mother will be mailing a stack of old sheet music to me, so I'll be able to refresh my memory, and eventually move on to the pieces I can't play anymore, but used to know very well. For now, however, there are three major things in this category:
"No Holly for Miss Quinn" -- this is an Enya piece off Shepherd Moons that I taught myself to play by ear. It's very simple, and I really can still play all of it; I just have to not let my mind wander, or I end up stumbling onto the wrong arpeggio. I've been using it as a warmup, and the goal is to get back to the point where I can reliably play it in my sleep.
"Solfeggietto" -- C.P.E. Bach. One of the last pieces I learned, back when I was still taking lessons. It's a fun, impressive-sounding thing, but the basics of it aren't that hard; it's just hard to play well. Right now I forget bits and pieces and have to jump past them to continue on, so I'll either need to cudgel my brain into coughing up the rest, or wait for the sheet music to arrive. Then it will be time to act like a grown-up and do the exercises my piano teacher set me back in the day, that I hated at the time. They're boring as hell, but kind of necessary to make sure you play the piece evenly, without the sixteenth notes lurching around like drunkards.
"Toccata and Fugue in D Minor" -- J.S. Bach. Learned this, or rather the first part of it, at the same time as "Solfeggietto." I remember much less of it, and will definitely need the sheet music to get all of it back. But it's also fun and cool-sounding (especially now that I can play it with an organ tone instead of a piano one). Barring a few bits, it isn't very hard, either.
The second category of music are the project pieces, i.e. the new songs I'm trying to learn. Right now there are two of these, both chosen for their relatively low difficulty level.
"Roslin and Adama (Simplified Version)" -- I reported on this before. I'm nearly at the point where I can play both hands together at tempo; it's just a matter of getting myself reliably back to the point where my fingers (especially on my left hand) remember their way around a keyboard well enough that I don't have to watch them all the time. I also tried the non-simplified version briefly last night, and nearly fell over with hysterical laughter -- I don't think I have EVER played a piece that actually used that much of the piano's lowest register. The amount of time spent counting ledger lines before I could play the next chord . . . yeah. My brain needs more of a refresher course before I can do that one.
"O" -- from the Cirque du Soleil show of the same name. Again, my left hand needs to remember more of its former competence before I'll have this one down; there are too many stretched arpeggios that it has to be able perform without direct supervision. But we'll get there.
I have a few other things I'm dinking at, but that's most of it. Now, if you'll excuse me, I need to go spend more time with the Precious . . . .
August 25, 2012
The Precious

We're talking a half-hour drive each way and a $5 bridge toll. To hang out with a friend too, sure -- but if it weren't for the piano, I would have been pressuring her to come to the Peninsula instead. ;-) And, as I said at the time, it made me really want to buy a keyboard for myself.
A year later -- well after she'd moved out of the co-op -- I was still thinking about it.
No, thinking is too mild a term. I was longing for a piano.
There's a store not far away that sells keyboards. I went and tried some out. Found one I liked. Went back today to play it more extensively, see if it was really the one I wanted. Was allllllllmost happy with it . . . then tried a keyboard one tier up in price.

Yeah. It's worth it.
The difference between this one (inadvertently dubbed "The Precious," due to a brief Gollum-like incident in the store) and the stuff one tier down is that in this one, each key samples not only the individual note, but also the resonance of the other 87 -- the strings that would be vibrating, if this thing had strings. The difference is very, very audible, if you play piano. And the touch is better, and, and . . . yeah. The Precious.
The touch is right, the pedal is right -- hell, even the texture of the keys is less plastic-feeling. It has more bells and whistles than the picture would lead you to believe; they're catering to a consumer like me, who doesn't want lots of buttons and LCD displays de-piano-ifying the look of the thing, but if you read the owner's manual, there's an impressively non-intuitive system for using those eight buttons to achieve some interesting effects. You can adjust the touch of the keys, and also the brightness of the sound, in addition to the usual ability to change basic sounds -- more than I really want, but I will admit the ability to play "Toccata and Fugue in D Minor" with the sound of an actual organ is gratifying. ^_^ And I appreciate both the built-in metronome and the headphone jack, especially since the latter lets me play while

And? It will never need tuning. <g>
So, yeah. I am now the proud owner of the most piano-like thing I could buy short of buying an actual piano. It makes me exceedingly happy. Look for more posts in upcoming days, as I begin my journey through remembering how to hell to play this thing . . . .
August 22, 2012
a disturbing thought
I know that I know women who have been raped. I know that I probably know more of them than I think, because not all of them necessarily have mentioned it to me -- or to anyone. This is horrifying, but it's a kind of horror I've gotten used to, in the sense that I understand this is a real thing in my life.
Tonight, I found myself thinking that I may very well know one or more rapists, too.
I can't be sure, of course, because it's the kind of thing people bring up even less than they bring up being the victim of rape. But I may know a guy (or a woman, but that's uncommon enough that I'll go with the assumption of a guy for now) who has raped someone. Not the hold-them-at-knifepoint kind of rape, maybe, but the sort where the other party didn't consent -- which is, yes, still rape. I may know a guy who slipped roofies into a woman's drink (or a man's), or just got her too drunk to know what he was doing. I may know a guy who climbed onto a sleeping woman and fucked her against her will. I may know a guy who coerced his victim with words, who did any one of the hundred things that guys write off as "not really rape" and therefore rest secure in the knowledge that they aren't rapists.
But they are. And maybe I know a guy like that.
It's easy for me to think, when I read about those kinds of cases, that the guys in them obviously deserve condemnation. That it doesn't matter whether they're "nice guys" the rest of the time; what they did is still rape and should be called such, without prevarication. That their friends need to accept that somebody they know and like did a horrible thing, and not try to defend the guy by shifting the blame onto the victim.
Then I wonder how I would react if somebody told me one of my friends raped them. How long it would take me to move past the "but he wouldn't do that!" reaction, and listen to what the victim has to say. To believe them, at the cost of what I believed before.
I hope I could do it. I hope I could, if the situation arose, swallow questions like "are you sure?" and "but didn't you . . . ?" and other things that would hurt somebody who's already been hurt too much. I think I could do it after a while, but in the moment itself, I'm not sure if my principles would beat out my partisan bias, my loyalty to that friend. I hope they would.
I hope that, if one of you ever comes to me and says somebody I know and like did a horrible thing to you, I will be able to face the fact that there is a rapist among my friends.
Because there might be one among them right now. And that's appalling in ways I'd never really thought about before.
August 21, 2012
tales of good customer service
Edited to add: and then one minute later, an e-mail asking if I could send a photo, just to speed things up.
Now let's see if Sprint can do equally well with my malfunctioning phone. Somehow I suspect not . . . .
August 14, 2012
swan_tower @ 2012-08-14T21:27:00
August 9, 2012
Not Being a Creeper: Two Examples
See, sometimes you get guys responding to this kind of thing by wailing that they'll never be able to compliment a woman again, or whatever. And that just isn't the case. You can say nice things to a woman, or even touch her -- or even try to hit on her! -- without weirding her out. Here's how.
A year or two ago,

He was totally not sketchy. In fact, he was really sweet and cute about it. In fairness, I will note that I got the impression he might be gay, which does indeed help the "I'm not here to skeeve on you" vibe. But there are a number of things he did right, that are totally within the reach of any human regardless of gender or sexual orientation.
1) When he approached us, he stopped outside of conversational range -- maybe half again or twice as far from me as

2) I believe (though I may be misremembering) that he bent or crouched down, so that he wasn't looming, either. Given that we were sitting, this was also nice.
3) He complimented our clothing, not how we looked in it. Like, "I just wanted to say that your skirts are really cute" -- not "you look great in those skirts." Major non-skeeve points! (And this can apply even in situations that are less about "cute." Telling somebody her dress is gorgeous is waaaaaay different from telling her it makes her look hot.)
4) Having delivered his compliment, and us having thanked him, he said "have fun!" and bopped off back to his friends.
Result:

But, I hear you say, that's just a passing compliment for your skirts. What if a guy is hoping to strike up an actual conversation? How does he do that without weirding you out?
Let's look at two hypothetical success modes for that, where "success" is defined as "being not creepy." Both start with the guy approaching as described, delivering his compliment, being thanked, and then saying, "What do you think of the concert?"
Hypothetical #1: I say, "It's fantastic! Kind of loud, though -- that's why were out here. But I've never heard either of these groups live before. How about you?"
I am, in this scenario, looking at the guy, responding to his question with information about myself, and asking him a question in return. This sends the signal that I am interested in talking to somebody new, not just my friend on the bench with me. Success! He can move closer (into normal conversational range), and so on from there.
Hypothetical #2: I say, "It's pretty cool."
In this scenario, I'm not really looking at the guy, and I probably glance at

No, he hasn't gotten the conversation he was hoping for -- but pushing wouldn't get him what he wants, either. His path to success is to accept that and go look for some other woman to chat with. There are many girls, and many concerts, and the world will not end if I don't want to talk to him. Acting like it will . . . that is a fast train to creepiness.
Given that a lot of the creeper-vs-noncreeper discussion has revolved around geek conventions, and that backrubs are a thing that come up a lot at such events, let's talk about how to offer one of those without skeeving the recipient.
I often have tension in my shoulders, and have been known to need a backrub. I do not, however, accept them from just anybody. Mostly I accept them only from people (male or female) I already know pretty well, because it's an interaction with a high risk of creep factor. But I've gotten enough offers that I can tell you pretty clearly how to do it without weirding me out. (Other people's mileage, of course, may vary. What I say here is general advice, but if you really want to be safe, confine your offers to good personal friends only. Or don't give backrubs at all.)
1) Don't offer to a total stranger. If she doesn't know your name, or hasn't been talking to you for the last hour, she probably isn't going to accept. So why waste your time and risk creepiness by offering?
2) Wait for a sign that she wants a backrub. If she's stretching her neck, or rubbing her own shoulders, or saying "god, my back is killing me," then this is a sign that she might be glad for some assistance. Don't offer out of the blue to a woman who doesn't seem to need one.
3) Phrase it in a way that makes it clear it's totally up to her. "Would you like a backrub?" or "I could give you a backrub, if you like." NOT "Let me give you a backrub!" Grammatically speaking, the first two are conditional, and the condition is the woman saying "yes." The third one is a command. Which do you think is going to make her feel more comfortable?
4) Do not, repeat, DO NOT touch her while offering. Don't even hold your hands out. Keep your hands to yourself unless and until you're invited to use them.
5) If she accepts, then stick to safe zones -- basically, the non-neck bits of the trapezius. If you want to do anything more, ask. Don't feel up her neck, go into her lower back, move her arms around, or reach further forward than the tops of her shoulders without saying "do you mind if I . . ." I have accepted things like a guy putting his arm across my collarbone to brace me, but only when asked first, and when I've been sure he's really just trying to work the knots out.
6) There's tension in the "knotted muscle" sense, and there's tension in the "I'm not comfortable with this" sense. A woman who wants the massage you're giving her will do her best to relax into it. If her whole body is stiff, she's not okay, and you should ask if she'd prefer if you stop -- or just cut the massage short.
7) If she says "thanks, but I'm okay," then accept it and move on with the conversation. DON'T PUSH. Pushing signals "I think I know better than you what you need" and/or "I don't respect your boundaries" and/or "I'm really eager to get my hands on you." In other words: creepiness.
So: guys! You are allowed to say nice things, to indicate interest, to offer touch! The key is not to push. Give the woman her space (which includes not approaching her at all if the circumstances aren't right), pay attention to the signals she gives in return, and if you're rebuffed, don't take it personally. She doesn't owe you anything. Speaking for myself, I can't recall a single instance where I've been offended by a guy who accepted my lack of interest. The offensive ones are the ones who ignore those cues and keep trying.
But remember, too, that I am speaking for myself here. I do not speak for All Women, and there may well be comments on this post expressing different views. This is why the #1 key to not being a creeper is to actually get to know the woman in question -- to learn what she's interested in, where her boundaries are, and so on -- before you venture anything that might come across as forward. Until you know that, play it safe.