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.

: First, let me just say that I love this thread... :)

Definitely one to remember.

: Second, I'll quote what I believe should be the end of our 'disagreement' -
: an agreement, imo, based on the original point...

: Point being - my impression was that you were saying non-humanoid vehicles
: will always be better than mechs.

And here, I realize the terrible, terrible mistake I made: I was using 'mech' and 'walker' interchangeably.

I was thinking that there are a few applications where the benefits of legs would actually outweigh their drawbacks. In these applications... well, I'll quote Orwell:

"Four legs good, two legs bad."

I remain unconvinced that bipeds are a good design for mecha.

: But here, I think we can agree that
: that's not the case; to whatever degree you mean. And so, all that's left
: below are discussions entirely in the realm of fiction, in various
: subjective contexts of feasibility, believability, and preference ;)

: Every property of some machine is something to design around. It's not
: positive or negative until it's given a practical context.

And just about every practical context I can think of promotes wheels over legs.

: Center of
: balance isn't a "problem" until the machine is put in a position
: where it is a problem. You're framing your point unfairly against mechs.
: There may be more situations where CoB is a problem than where it isn't,
: but that's not the same as saying it Is a problem. So it comes back to
: whether there are situations where mechs are more useful than non-humanoid
: vehicles. (which you ceded above)

As I said before, I meant to cede no such thing.

: erm, then we have different ideas of what defines 'space magic'. If something
: can't be done now - whether 'logical' or based on sound science or not, I
: consider that "space magic", however believable or feasible.

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

: It only works because the writers say it works, with no practical
: demonstration that it can or will. Extrapolating forward from good science
: - extending knowledge into an unknown context - is space magic. At least,
: that was how I was using the term. :P

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.

Element Zero is unobtainium, because it has a simple effect (Reduce/increase mass of surrounding material) and the writers envisioned how that would affect society, and what it would be used for. (Hint: Completely, and everything, respectively)
Of course, some of Eezo's applications are suspect. I'm not sure how /realistic/ biotic powers are, given what we know about element zero. I will say that I don't think that Samara should be able to heal herself with biotics (Reave).

The Unobtainium in James Cameron's Avatar is a purer form of unobtainium. I mean, it's a room temperature superconductor. Something like that SHOULD be possible, would have the uses described in the movie's supplementary material, and would be worth its weight in Na'vi blood if it existed.

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.

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

: meh, different properties of entities that are built to accomplish some feat
: or feats, specialized or general. All different contexts and purposes,
: whether biological or not. Then we start to get into the line between
: human and machine; android, robot, cyborg, yadda yadda. Where would you
: draw the line?

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.

A robot is a machine.
An android is a machine with integrated biological systems.
A cyborg is a human with mechanical augments.

There is the edge case where a human mind is augmented with machinery. I would say that most functions of the brain (memory, control of bodily functions, ect) could be taken up by computers, and a person would still be human. But if the portions of the brain that do the actual thinking, where self-awareness occurs are augmented by machinery...
Hell if I know. It was 2:00 in the morning when I typed this.

: Apples & oranges. :P

Exactly. Power armor isn't the same as a mech.

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.

: (from what I'm arguing - not labels but practical
: uses of vehicular tools)

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.

: I don't see "sufficiently advanced" as a maximum limit, but a
: minimum limit.

It's a maximum limit for technology.

: Once it's past a certain point of advancement, it becomes
: magic. I suppose that limit is what's up for debate. Is the line drawn at
: current technology? Or current technology plus an increase of a property
: that is still feasible in theory?

Current technology with an increase in performance is a good place to start.
I also like to make allowances for stuff that's theoretical, but feasible. An example would be nanotechnology that doesn't violate thermodynamic laws.

: (eg, give it more power,

: Or the
: implementation of a fantasy technology that does not exist, and only
: exists as a some form of 'potential' future ability? Or something like
: that... I'm sure I'm not using the best words :P

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.

So, Avatar unobtainium: I have no clue how a room temperature superconductor would work, but I know a bit about superconductors, and I also know that their operating temperature has been rising for a while.

Contrast blamite, the pink crystals in needlers. It's a homogenous crystal with an inert and an active state. In the active state, it appears to be self-propelled and it guides itself towards biological and mechanical enemies. It's also capable of determining when a sufficient number of needles have embedded themselves for an effective supercombine, which is probably simpler than the guidance and target-acquisition.

I can describe what blamite does, and what it probably does, but I can't begin to theorize how it does it. So, sufficiently advanced technology.

: Travel to the future first, when mechs are as feasible to create as vehicles,
: with knowledgeable, professional mech engineers, then ask me again.

Just got back from the future. 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.