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canonical

   usual or standard state or manner of something.  This word has a
   somewhat more technical meaning in mathematics.  Two formulas such
   as 9 + x and x + 9 are said to be equivalent because
   they mean the same thing, but the second one is in `canonical
   form' because it is written in the usual way, with the highest
   power of x first.  Usually there are fixed rules you can use
   to decide whether something is in canonical form.  The jargon
   meaning, a relaxation of the technical meaning, acquired its
   present loading in computer-science culture largely through its
   prominence in Alonzo Church's work in computation theory and
   mathematical logic (see Knights of the Lambda Calculus).
   Compare vanilla.


   This word has an interesting history.  Non-technical academics do
   not use the adjective `canonical' in any of the senses defined
   above with any regularity; they do however use the nouns `canon'
   and `canonicity' (not **canonicalness or **canonicality). The
   `canon' of a given author is the complete body of authentic works
   by that author (this usage is familiar to Sherlock Holmes fans as
   well as to literary scholars).  `*The* canon' is the body of
   works in a given field (e.g., works of literature, or of art, or of
   music) deemed worthwhile for students to study and for scholars to
   investigate.


   The word `canon' derives ultimately from the Greek
   `kanon'
   (akin to the English `cane') referring to a reed.  Reeds were used
   for measurement, and in Latin and later Greek the word `canon'
   meant a rule or a standard.  The establishment of a canon of
   scriptures within Christianity was meant to define a standard or a
   rule for the religion.  The above non-techspeak academic usages
   stem from this instance of a defined and accepted body of work.
   Alongside this usage was the promulgation of `canons' (`rules')
   for the government of the Catholic Church.  The techspeak usages
   ("according to religious law") derive from this use of the Latin
   `canon'.


   Hackers invest this term with a playfulness that makes an ironic
   contrast with its historical meaning.  A true story: One Bob
   Sjoberg, new at the MIT AI Lab, expressed some annoyance at the
   incessant use of jargon.  Over his loud objections, GLS and RMS
   made a point of using as much of it as possible in his presence,
   and eventually it began to sink in.  Finally, in one conversation,
   he used the word `canonical' in jargon-like fashion without
   thinking.  Steele: "Aha!  We've finally got you talking jargon
   too!"  Stallman: "What did he say?"  Steele: "Bob just used
   `canonical' in the canonical way."


   Of course, canonicality depends on context, but it is implicitly
   defined as the way *hackers* normally expect things to be.
   Thus, a hacker may claim with a straight face that `according to
   religious law' is *not* the canonical meaning of `canonical'.