Path: utzoo!attcan!uunet!cs.utexas.edu!rutgers!aramis.rutgers.edu!moncam.uucp!harry
From: harry@moncam.UUCP (Jangling Neck Nipper)
Newsgroups: sci.nanotech
Subject: Re: Is active shield design intractable?
Summary: Mode and reason for attack determines complexity.
Keywords: active shields, cultural evolution
Message-ID: <8906150843.AA06321@athos.rutgers.edu>
Date: 14 Jun 89 19:28:01 GMT
Sender: nanotech@aramis.rutgers.edu
Organization: Monotype ADG, Cambridge, UK
Lines: 25
Approved: nanotech@aramis.rutgers.edu


> There is clear asymmetry between the difficulty of destruction and the
> difficulty of maintaining a complex integrated system such as a
> building, workstation, standard of living, or human body.  To destroy
> is relatively easy, to protect against destruction is much more
> difficult.

This is not true; the sophistication of the attack determines the
sophistication of the defence.  Something like a physical blow simply
needs to be avoided, but something like a complicated toxin, or a
virus need more sophisticated defences.  Also, I think you are confusing
the defender and the defence response here; any system is the sum of
all its attacking modes and its defending modes.  The reason that the immune
system is so complex is because it has to deal with lots of >different<
kinds of attack, but on a one-to-one confrontation of, say, toxin to
anti-toxin, the complexity is similar, and, moreover, the complexity
of >producing< both the toxin and the anti-toxin are also similar.
Anything capable of producing >all< the toxins of >all< the bacteria &c.
would be as complex as the immune system; the `simplicity' of a toxin
is because it >is< just one toxin, and not all of them.

In fact, if you look at warfare, the aggressor's technology is much
more complex and costly than the defender's, mainly because attacking
invloves lots of moving around, which is more diffult to do than
staying still, eg, tanks are more complicated than mines.