I'm pessimistic about non-lethal means of self-defense (that's unlike me, I know). I think that it's very difficult to design a "self defense" mechanism which is not a form of attack, no matter how softly softly it works; these things can be used on non-attackers as easily as attackers.
Glen Finney put forward 9 qualities of a non-lethal weapon. I have tacked them on the end of this message; if you haven't read them, go have a look.
There is an assumption which must be made when designing this kind of all-purpose non-lethal weapon, which is that lethal weapons are also available. Glen works under this assumption - I'm just making it explicit.
A corrolary is that non-lethal weapon must be able to defeat the best lethal weapons, or make a good stab at it (ha ha). The kind of nice-gun style weapon described in Glen's post seems doomed to be second rate, because pushing a bit of speeding lead real fast is easier than any of the round-about nice-gun solutions, which also involve firing a (perhaps complex) projectile, with all kinds of other burdens (like non-lethality) to contend with.
My other objection to the idea of non-lethal weapons is that they are still weapons. A weapon with the qualities that Greg described would appear to be a rapist's weapon of choice! Imagine being shot in the streets of a big city by one of these devices. How long do you have to lie there, totally helpless, before you regain control or someone comes to your aid? What happens to you during that time, especially if your attacker is still around (which seems likely)?
Jeff Davis added:
> I had a similar thought about non-lethal warfare--enemy soldiers
> incapacitated and captured rather than, well, you know,...mutilated and
> killed. That thought originated from the idea that, after all, soldiers
> are really just pawns, essentially innocent victims, so that a military
> technology which was effective without being lethal would be very
> from a moral standpoint. However, that's an idea for another thread.
This would just annoy a lot of militaries... it means you have to run around killing all those slumbering enemies, because you have no capacity to take prisoners. Much easier, more reliable, and far cheaper to fill 'em full o' lead.
They could use them in wargames, however; that'd make the contests pretty vivid (especially if the non-lethals really hurt).
[snip stuff about hi-tech version of "hue and cry"]
> Granted, such a device is likely to be severly limited in "stopping power"
> once an attack has been initiated, but I wonder if it wouldn't created an
> environment where such attacks would be substantially pre-empted.
"Hue and cry" can be used as a weapon also - "He tried to attack me, lock him up!"
- and I think this would be its downfall. People might end up tuning these devices out
also, so they become more background noise like people shouting and car/building
alarms going off. This is a better approach though in that it cannot be used to render
someone defenseless in order to take advantage of them.
On the subject of creating an environment of no-violence, a good weapon defense one which consists of a really big bomb attached to a person, with a deadman switch. The wearer dies, the bomb goes off. This has some drawbacks; fun with sniper rifles comes to mind, and the recursive effects are just plain scary (anyone ever written a flood-fill algorithm?). Maybe the weapon has to be smart, to identify the attacker, and not go off if it cannot identify such.
This conjures the image of people walking around with big red, orange and yellow backpacks on. A signal to would be attackers: Don't eat me, I taste bad.
> It goes without saying that anyone who wants to should take this idea and
> run with it. For example, the cloud of smoke could be tear gas, nausea
> gas, or some super stink bomb--powerful enough to disrupt the attack--yet,
> happily, harmless. Improvements anyone?
Gas/smoke grenades + a gas mask would appear to be a formidable weapon! Better
yet, just pop a nerve gas canister in the launcher, and voila!
The extropian solution in the (far flung) future would have to be personality backups. If you are uploaded in some form, but still move about the physical universe, you would have master backups of yourself stashed in multiple places, with incremental updates being sent of relatively frequently (every hour or two? ever couple of seconds?). So someone nukes your ramship. Big deal. You get restored from backup, and continue on your way; not one of the better events in your life, but non-lethal and not a weapon. Except maybe you can nuke yourself, killing yourself and everyone nearby, and all without backups are really dead. Then again, they really should have been being backed up (when will they ever learn?).
Then of course someone creates mental viruses which act over time... by the time it kills you all your backups are toast too. Well, you've got to die sometime; or restart from your first upload.
Appendix: 9 qualities of non-lethal weapons from Glen Finney
expect anyone to trade in a proven effective weapon for one of inferior ability, not when so much is on the line. Preferably, we want a weapon that
only needs to hit approximately center of mass, can usually immobilize with one application, and completely incapacitates the aggressor. Also, the weapon needs to be able to penetrate some degree of obstacles (be effective through clothes, for example).
5) Speed & Reusability - The weapon should be able to be brought into use rapidly, and be able to be reused several times in rapid succession in case the aggressor is missed the first time, is not completely incapacitated with
one strike, or there are multiple aggressors.
6) Accuracy - We want a weapon that can hit the target most of the time. This should be obvious. Precision would also be nice, but is slightly less important in a truly nonlethal weapon (indeed, the need for precision is inversely proportional to point 7).
7) Safety & Reversibility - Nothing I know of is perfectly safe, but the
ideal here is to make the weapon as safe as possible. This is especially
important to prevent accidental harm. Likely we want a weapon which with
time is completely reversible, and has low morbidity and mortality (it can
unpleasant though<g>). Ideally, the effect of the nonlethal weapon would not
be mass dependent (we don't want a weapon that a big enough attacker can shrug off and/or that is dangerous to small children).
8) Duration - Our nonlethal weapon's effects need to reliably last long enough for more permanent arrangements to be made to neutralize an aggressor.
9) Portability - Our nonlethal weapon needs to be able to be light and compact enough for most of the population to easily carry on their person.