From: kjm@buc.edu.au (Kevin Moore)
Newsgroups: bionet.info-theory
Subject: Re: More wacky theory
Date: 15 Sep 92 20:23:54 GMT
Distribution: bionet


mshute@cs.man.ac.uk (Malcolm Shute) writes:

> The paradox, or problem, or however you like to view it, then, is how
> to distinguish between the CPU hardware, which has no *regular* structure
> to summarise succinctly, but never-the-less has *a* structure for a purpose...
> and the random noise pattern, which also has no *regular* structure, but
> has no meaningful purpose for its particular pattern either.
>
> Phrased like this, we are going to have to define complexity (and information
> content, etc) in terms, not only of regularity of its structure (or lack
> thereof) but also the nature of the job that it is designed to perform.
>
Which is presumably why Shannon talks purely in terms of information
channels in his seminal papers. The message has to be interpreted, whether
by a molecular machine, or by a human brain, for information transfer to
mean anything.
> 
> This then comes back to my comment last week, from Richard Dawkins' "The Blind
> Watchmaker".  Mont Blanc is a complex structure... with millions of fragments
> of intricately shaped rocks making it up.  However, much of this complexity
> is random.  Mont Blanc would still do the same job if someone where to come
> along and muddle up some of its rocks, or even replace some of them.  However,
> a CPU would not work if you swapped a couple of its leads over, or replaced
> them with something else.
> 
> As far was we know, then, the CPU is more complex (has more intentional
> structure) than Mont Blanc.
> 
> However, as "Hitch Hiker's Guide to the Galaxy" fans would be quick to point
> out, we're only assuming that Mont Blanc would perform the same job with its
> components mixed up a bit.  How do we know that it isn't an extraterrestial's
> computer, with every fragment of rock performing a specific function?
>
A nice illustration of the point that a personalist viewpoint is necessary
in dealing with information theoretical ideas. The channel

ACME
Extraterrestrial --------> Mont Blanc --------->Informed Extraterrestrial
Computer
Company

clearly carries more information than the channel

ACME						 You or I in Blissful
Extraterrestrial --------> Mont Blanc ---------> Ignorance of the REAL
Computer 					 Purpose of Mont Blanc
Company

in this case. The "bitstream" is the same, the difference lies in the
interpreted message. You or I interpret it as "Mont Blanc is a pile of
rocks", while the extraterrestrial percieves a highly sophisticated
computer. A crystallographer with more patience than common sense might
well resolve the entire structure of the mountain, which, while it is a
perverse thing to do, requires more information than the computer
interpretation.

Perhaps we should be thinking in terms, not of the complexity of the
object itself, but in terms of the complexity of the information required
to fully describe its function. The randomness you mention is then simply
complexity which is irrelevant to function. Of course, as you have ably
illustrated, functionality is dependent on the observer's sophistication.

> So, clearly this is a blind alley, too, as a means of defining complexity
> of structure.  It would work fine for things that *we* have designed, but
> not for things like Mont Blanc and the Universe... (where there is some
> argument over whether they *have* a purpose, let alone *what* that purpose is)

What was it that Keats said about clipping angels' wings?

***************************************************************************
Let there be light			*      	Kevin Moore
	Bomb number 20			*   kjm@eureka.buc.edu.au
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