Subject: Re: LISP and AI
From: Erik Naggum <>
Date: 2000/05/09
Newsgroups: comp.lang.lisp
Message-ID: <>

* Espen Vestre
| ok, I was thinking in terms of old-fashioned bibliographic
| references printed on dead trees (disregarding any software which
| might be involved in producing it), which basically is a simple
| one-way pointer which involves only two documents ...

  This is unfortunately a very misguided view of the old-fashioned
  bibliographic reference.  I'm sorry to say so, but the bibliographic
  reference includes a lot more than one-way "pointers", which is a
  special case or a narrow view, depending on how you look at it.  If,
  for instance, I wish to compare CLtL2 with CLtS (S for Standard),
  you can either regard my two bibliographic references in any given
  comparison on a given point as two one-way pointers from my document
  into those two documents, but that is very nearly irrelevant to the
  purpose and actual references involved.  A reader of a comparison
  would naturally want to have both text available and would have to
  regard my commentary on their _relationship_ as the real purpose of
  my text.  My document thus contains third-party hypertext links (and
  bibliographic references) with that purpose between two other

  This may not be all that obvious to a reader of modern literature,
  but pick up any commentary on religious writings and track down the
  references to the Bible, say.  This is a lot more explicit than the
  intertwined legal world I referred to, but it also less available to
  most people today.  (I wouldn't know about it all were it not for
  the many people who use SGML and HyTime for dealing with the rich
  set of references in precisely such literature.)

  On the other hand, what you refer to as "old-fashioned" may be a
  trivialization of the bibliographic reference into the _expression_
  of a bibliographic reference that follows certain formal rules.  The
  fact that there is an enormous number of ways to express a reference
  (such that actually locating the document that has been referred to
  may be very, very difficult), should not obscure the more abstract
  concept.  Instead, I'd hope that the plethora of ways to refer to
  texts should communicate the failure of trivializations to capture
  the author's (or indexer's or librarian's) purpose and intent.