definition of "meta"

[Jul,Erik]

	On Mon, 2 Mar 1998, Roy Lewis wrote:

	> I have been looking for an official definition of "meta" as in
"metadata" 
	> and this link did not have a listing of either.  Does anyone
have a source 
	> for a good definition?

To which Joy Schwarz [schwarz at AXP.WINNEFOX.ORG] replied (with the actual
definitions supplied by me in square brackets):

> You'll find one definition at The PC Webopaedia
> <http://www.pcwebopedia.com/meta.htm>, 
> 
	[In computer science, a common prefix that means "about".]

> and another at The Jargon File
> <http://www.lysator.liu.se/hackdict/split2/meta.html>.
> 
	[One level of description up.]

	These definitions are not totally satisfying to me.

	First, etymologically, "meta" derives from ancient Greek.  It is
a preposition and can have various meanings.  In terms of "metadata,"
one sensible meaning is "along with," or simply "with."

	Thus, metadata is that data (or information) that accompanies
(is along with) other data (or information).

	What is the purpose of this "with-data"?  Metadata provides the
context, or the necessary additional information, whereby one can
properly derive or interpret meaning.  This extended meaning often gets
collapsed into the short-hand definiton, "data about data," and, worse,
the assertion that "meta" is a "prefix that means about."

	Meta does not mean "about."  At least we can avoid that mistake.

	The second definition, above, that is, "one level of description
up," suffers from a centuries-long confusion about the title of
Aristotle's "Metaphysics," so titled because it "came after" (another
meaning of "meta") his treatise, "Physics."   Because the subject of
"Metaphysics" is higher-order first principles, philosophers and
neologists through the years have co-opted "meta" as a way of invoking
the notion of a higher order, a meaning never intended or understood by
Aristotle.

	So, neither "aboutness" nor "higher order" are part of the
original meaning of "meta."  These meanings have crept into our
vocabulary through usage over time.

	It might be useful to revert to a definition of metadata as,
simply, "accompanying data or information" or, by extension,
"accompanying data or information that provides a context for
understanding or interpreting the primary data."  (It's easy to see why
shorthand definitions are invented.)

	For your consideration,

	--Erik

	Erik Jul
	jul at oclc.org