Douglas Hofstadter's 3-level message model

John Cowan cowan at
Mon Jun 22 23:38:17 BST 1998

Let me introduce, for those of you who don't know it or have
forgotten the details, Douglas Hofstadter's model of messages
as containing three levels:

	The <DFN>frame message</DFN> says "I am a message,
	decode me if you can!"

	The <DFN>outer message</DFN> tells how to decode the
	inner message; if put into words, the outer message
	of *this* message would say something
	like "This message is encoded in ASCII and written in
	the English language".

	The <DFN>inner message</DFN> is the actual content
	intended by the DC:Creator.  (:-))

If you do not understand the frame message, you fail to recognize
the message as a message; to you, it is just a bunch of chicken tracks,
or bits, or whatever.

If you do not understand the outer message, you recognize that you
have a message, but (like an archaeologist confronted with the
Phaistos disk or Easter Island rongo-rongo) have no clue what
it says.

If you do not understand the inner message, then you have the
formal requisites for reading the message, but its meaning
escapes you.

Note that neither the frame message nor the outer message can be
part of the inner message: to one who does not understand the
frame message, putting "This is a message" at the top of the
inner message is useless; likewise, saying "This message is in
English" is only useful to those who already understand English.

>From this perspective, metadata is an attempt to make the inner
message of one message contain the outer message of another, and
if interpreted naively, leads to an infinite regress.  Somewhere
there must be a core of messages whose understanding is hard-wired
into the system, which permit all other messages to be bootstrapped
from them.  At present, the only way we know to create such
universally understood messages is to write messages in some
(human or programming) language which can be presumed to be understood
everywhere.  The fact that no such language(s) exist is the
rationale for struggling to create them.

And see my .sig for another view of this.....

John Cowan		cowan at
	You tollerday donsk?  N.  You tolkatiff scowegian?  Nn.
	You spigotty anglease?  Nnn.  You phonio saxo?  Nnnn.
		Clear all so!  'Tis a Jute.... (Finnegans Wake 16.5)

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