: The storm had now definitely abated, and what thunder there was now
: grumbled over more distant hills, like a man saying "And another
: thing…" twenty minutes after admitting he's lost the argument.
: -So Long, and Thanks for All the Fish.

<3 Adams.

: I'll quote Orwell: "Four legs good, two legs bad."

And in my opinion, this is certainly true given our level of scientific achievement and discovery and capability. *shrug* Science fiction? Be creative. But believably creative. Space magic or not :P What I believe is feasible clearly doesn't seem to be shared by you (or vice versa).

: So, you have no concept of the difference between hard science fiction and
: soft, gooey science fiction like X-Men?
: I... don't understand.

X-Men I consider more fantasy (super powers; biological origin at least) mixed with sci-fi (the stuff people create/use with those super powers and enhanced knowledge yadda yadda).

: Try this on for size: Unobtainium. It's an ideal material that we don't have,
: and probably doesn't exist, but these are the properties of the material
: and how it would behave. How it would be used.

Ahh unobtanium; space magic at its finest!
I chuckle whenever I hear it mentioned, whether Avatar or The Core, or anywhere else.
Plot device'd! "I combined the crystals in a tungsten-titanium matrix at super-cool temperatures, and that's what did the trick! / What do you call this material? / Well it's real name has 37 syllables. I call it Unobtanium."
It's a label that was made up and essentially now used by any writer who wants to employ some element that doesn't (yet?) exist on the periodic table to accomplish a task no element that exists on the periodic table can perform. Whether believably similar to an existing element or not, IMO: space magic. :P

: Hardlight... doesn't function on any known principles, we don't know anything
: about the science behind it, what it does is left vague. It's pure
: handwavium, there because 343i wanted to disintegrate Prometheans and
: structures at will. Space magic, though not as pure as the Force.

Hard light was in Halo 1 for bridges, though I've seen the discussions/debates about its implementation and what it actually was/may be. Taken on the surface - this is a game element on which 343 seems to be basing its hardlight uses. Love it or hate it or debate it. The concept of 'hard light' existed, on the surface, before 343 took the reigns. They're just running with it, and saturating the environments with it. Love it or hate it. Still space magic :P

: To quote David Langford, "Any sufficiently advanced technology is
: indistinguishable from an ad-hoc plot device."

Yep. Some love it, some hate it. :)

: Hypothesis: human is biological. It is a biological brain that has
: cognizance. A machine is mechanical. It is a computer which has awareness,
: which thinks.

I differentiate biological from mechanical purely in that line between "running" by a means we are able to accomplish (manufacture/construct material; flip a switch), versus not (we cannot give that 'spark of life' to the molecules, which we could assemble, in order to make it "run"). Beyond that fundamental step, humans and robots are machines. Theoretically (ie via space magic), we could 'construct' a human by coordinating molecules (eg Tron or Star Trek transportation), but somehow we'd need to recreate that 'spark' of life. Tron/ST presume that the reconstruction somehow includes that 'spark' to make the reconstituted biological machine (continue to) tick.

This is one reason I absolutely love the Halo AI, because it deals with what some entity alive; Cortana being a (space magic'd) duplicate of Halsey's brain. She has personality, intelligence, capabilities that match Halsey, but without biological limitation, only technological. Is Cortana alive? Is she just a program running code (which btw wasn't hand-coded, but machine generated based on a template, the cognitive impression modeling process). Cortana isn't a biological machine, but is she alive? (that's rhetorical :P)

: Exactly. Power armor isn't the same as a mech.
...
: So... if I understand you correctly, power armor is a mech because it uses
: similar technology/concepts, and is thus a vehicular tool?
: Is my chainsaw a 'vehicular tool'? It's got a gas engine, and the chain isn't
: all that different from the timing chain in my Mercedes. I mean, one has
: blades, the other is rated to fifty thousand miles, but it's the same
: concept.

Where do you draw the line? If you defined power armour as say a wearable machine that enhances your capabilities without hindering your normal actions, then I'd say yeah that's different than a mech. I'd say a mech is a wearable machine which is more akin to the human being the pilot, than parts of the human being enhanced by a frame. The question is where is the line between those classifications? A mech (humanoid, based on what I'm arguing) IS an enhancement of human capability; it's a large machine that mimicks to some degree the construction of the human biped, but built and augmented with various levels of accessories, designed for specific tasks.
A chainsaw isn't power armour. It's not a vehicular tool. It's a tool, which hinders normal actions (you hold it and carry it, you're hindered), but provides an additional benefit to a certain area of the human form. Add a chainsaw to framework the human wears (that is, sits on/above the human framework so as to be much less of a hindrance to normal activity) that can be activated and used at some point, and it could become a part of power armour :P but it's certainly not power armour itself. Obviously a mech that the user pilots is a hindrance to that individual's non-encumbered normal activity; which is why I wouldn't consider a mech to be power armour; but it's still an enhancement to certain biped capabilities. And being piloted (moving the driver, rather than being moved by the occupant, it would be vehicular).
(repeat disclaimer: the words I use may not be 100% accurate, but read the spirit of my comments instead of the strict definitions ;)

: Power armor fits the user like, well, armor. It augments the user's strength,
: endurance, etc. It's supposed to enhance infantry while still letting them
: be infantry. They can ride in vehicles, enter houses, do whatever you need
: infantry to do on the battlefield.

: Mechs and walkers are large enough that you no longer wear them, you pilot
: them. They're vehicles that can't perform the same role as infantry, even
: if they do look like a giant metal samurai.

Right.

re: "Sufficiently advanced"
: It's a maximum limit for technology.

potatoes potahtoes. half empty / half full. maximum / minimum.
I'm saying it's the limit at which anything above is considered "magic" (or "plot device"). Seems we're debating whether that limit is here, there, a defined range, or a blurry region.

: I guess I have a very broad definition of what space magic is. If something
: looks like a straightforward evolution of our understanding of technology,
: I say that it's future technology. If a technology plays nice with the
: laws of physics and is applied consistently, I call it science fiction.
: Generally, I think I need to know what it does, and be able to understand the
: underlying principles of a technology.

Personally, I consider space magic (like you, in a broader sense) the use of some technology that does not exist, or is some arbitrary distance from that feasibility limit from current technology I described above in order to accomplish some feat. To me, science fiction is all about space magic, at least if it uses technology that hasn't been invented yet, or is sufficiently 'distant' from our current tech capabilities (which is subjective to me, really). To bring it back, Halo 4 has moved much further into Space Magic territory than Halo 1 was. And has introduced much more fantastical (fantasy-like) content than Halo 1 had.

: Just got back from the future.

Space magic!

: Mechs are in common use throughout the battlefield.
: This is only possible because all of mankind has been
: uploaded into the UniServer. Battles are fought in virtual warzones, where
: the laws of physics and the properties of individual objects are
: arbitrary. I have seen combat between mechs of all shapes and sizes, just
: as I have seen the P. 1500 Landkreuzer lay siege to Gibraltar as American
: zeppelins battled flying U-Boats.
: Now if you'll excuse me, I have to pay the Patent Office a visit.

http://youtu.be/mLNrLI3OBwg !