This is discussion archived from a time before the current discussion method was installed.
Working Title: Equivalent Exchange: From YKTTW
Aswilson: It seems to me that there's two separate tropes being covered here: a scientific principle of magic roughly analogous to the laws of thermodynamics, and more of a philsophical no-free-lunch type thing.
Earnest: They are being roughly equated as the same thing though, in the sense that the emotional cost provides the "thermodynamic"/metaphysical oomph to get the spell/wish going. I don't quite see how these are two separate tropes though. Examples?
Later: wait, I think I get what you're saying: Nothing comes without cost vs. magic needs fuel. The latter is this trope, but it deals with the former often. If you want to make a more general fictional trope on how a hero wanting something causes drama and necessitates sacrifice to get, I think it'd do well as a YKTTW.
Eleanore: I removed this "*** It's quite possible that Equivalent Exchange is not an actual law of magic in Tsubasa, it's just Yuuko choosing to be a Magnificent Bastard." Concerning xxxHOLiC since the manga have pretty much shown Yuuko isn't doing it by choice and that it interfers with her so much that she can't even give someone a normal birthday present because of this trope.
Vampire Buddha: Cut out this pile of natter from the Full Metal Alchemist example. This isn't Just Bugs Me, people! (Oh, and for the record, sand is mostly made of silicates; there's very little carbon in it.)
- *** There's an even more subtle point made earlier in that episode — as Ed and Al walk through the desert, Ed mentions that he's starving. Why doesn't he just transmute some basic foodstuffs? Well, the desert doesn't contain the raw elemental material to make them!
- Wow, Fridge Brilliance. The first temptation of Christ in the desert. Didn't notice that one.
*** I'm certain that you could turn sand into food with it's basic elements... at the very least, I'm pretty sure that air + carbon based rocks in the sand (granite) would have enough hydrogen, carbon, and oxygen to create basic sugars essential for life. But yeah... Fridge Logic is a harsh mistress.
**What the show was probably trying to do was delay The Reveal that Ed can transmute without a circle. They were going by the logic that "you can't draw a transmutation circle in the sand" up to the point where Cornello sics a chimera on him in a sand-filled room. When you think about it, that moment would have been a lot less dramatic if we knew what Ed was capable of beforehand.
** But the writers for the anime's Gecko Ending decided that the alchemist's effort and energy weren't enough to be considered equivalent. So it turns out that the rest of the cost is covered by consuming the souls of people who die in the world on the other side of the Gate. Our world, specifically.
*** A near identical twist is put on Amestrian alchemy's power source in the manga. Minus the "from another world" thing. By comparison, Xingian Purification Arts run off of geothermal energy.
** If they can't transmute elements, then how does Ed change rocks into gold later on? (And why would there be an explicitly referenced law against alchemists doing so?)
*** It's made clear that all this gold he "made" was fake, and Pyrite (the Fool's Gold) is easy enough for an alchemist to make, it only takes iron and sulfur, and he had more than enough of these somewhere there.
***Actually he turns coal (or whatever those rocks were) into bricks and then covers them in a veeeeeery thin layer of actual gold from the gold coins he was bribed with earlier.
- Wow, Fridge Brilliance. The first temptation of Christ in the desert. Didn't notice that one.
