• normalization, reduced variation
• improved retrieval
• better, smarter tools
• semantic verification
• better documentation

• normalization, reduced variation
• improved retrieval
• better, smarter tools
• semantic verification
• better documentation
• ... but mostly because it's interesting.

• Simons 1997 (translating between marked up texts and database systems)
• Sperberg-McQueen and Burnard 1995 (informal introduction to the TEI)
• Langendoen and Simons 1995 (also TEI)
• Huitfeldt and others in Bergen
• Renear and others at Brown University
• Welty and Ide 1997 (querying using knowledge representation system)
• Wadler 1999 (XSLT)
• Ramalho et al. 1999 (semantic verification)
• Sperberg-McQueen, Huitfeldt, Renear 2000

<p><del>It was be</del> <del>For</del> 
When we applied to Your Excellency for 
leave to adjourn it was because 
we foresaw that we <del>were</del> 
<add>should continue</add> 
wasting our own time ... </p>

• paragraph(elem-1).
• deleted(contents(elem-2)).
• deleted(contents(elem-3)).
• deleted(contents(elem-4)).
• added(contents(elem-5)).

• parts of (components of?) the text
• words or characters within the content of an element

paragraph(____).
deleted(_____).

• Part and whole are not the same (distributed and non-distributed properties).
• Some inferences may be incompatible.
• Properties of n arguments (n > 1)
• Predicates in real systems frequently take arguments other than "the contents of this element" and "the value of this attribute on this element".

<doc lang="en">
<p>Wittgenstein wrote:
<q lang="de"><ital>Die Welt ist alles,
was der Fall ist.</ital></q>
It is hard to escape, at first reading,
the suspicion that Wittgenstein is guilty
here of a gross platitude; it is only
after reading the rest of the
<bibl>
<title lang="la">Tractatus</title> 
</bibl> that on returning
to its famous first sentence one appreciates
the depths of its intension.</p>
</doc>

node(n1, element(doc)).
path(n1,[1]).

attr(n1, lang, "en").
node(n3, pcdata("
")).
path(n3,[1,1]).
node(n4, element(p)).
path(n4,[1,1,2]).

node(n5, pcdata("Wittgenstein wrote:
")).
path(n5,[1,1,1]).
node(n6, element(q)).
path(n6,[1,1,1,2]).

attr(n6, lang, "de").
node(n8, element(ital)).
path(n8,[1,1,1,1,1]).

node(n9, pcdata("Die Welt ist alles,
was der Fall ist.")).
path(n9,[1,1,1,1,1]).
node(n10, pcdata("
It is hard to escape, at first reading,
the suspicion that Wittgenstein is guilty
here of a gross platitude; it is only
after reading the rest of the
")).
path(n10,[1,1,3]).
node(n11, element(title)).
path(n11,[1,1,2,4]).

attr(n11, lang, "la").
node(n13, pcdata("Tractatus")).
path(n13,[1,1,2,1]).
node(n14, pcdata(" that on returning
to its famous first sentence one appreciates
the depths of its intension.")).
path(n14,[1,1,5]).
node(n15, pcdata("
")).
path(n15,[1,3]).

• Node n1 is a document (doc(n1).)
• The document is in English (lang(n1,"en").)
• Node n4 is a paragraph (p(n4).)
• Node n6 is a quotation (q(n4).)
• The quotation is in German (lang(n6,"de").)

• The paragraph is in English (lang(n4,"en").)
• The italics are in German (lang(n8,"de").)

• The italic phrase is a document (doc(n8).) — part and whole are different.
• The italics are in English (lang(n8,"en").) — incompatible inferences.

• Tractatus is not just a title; it's the title of the book described by the <bibl>.

• representation of the document (Prolog representation / DOM / ...)
• generic routines for applying predicate functions to document and generating statements about it (ad hoc? XSLT?)

• set of predicate functions (skeleton sentences) describing the meaning to be attached to each construct
• set of deictic expressions to fill blanks in sentence skeletons / provide arguments for functions
• categorization of predicates according to inference rules (distributed / non-distributed, ...)
• (optionally) rules allowing further inferences from the properties directly predicated by the markup (e.g. "if something is an author, and not identified as a corporate author, then it is a person", or "if something is a person, then it is human")

<doc lang="en">
<p>Wittgenstein wrote:
<q lang="de"><ital>Die Welt ist alles,
was der Fall ist.</ital></q>
It is hard to escape, at first reading,
the suspicion that Wittgenstein is guilty
here of a gross platitude; it is only
after reading the rest of the
<title lang="la">Tractatus</title> that on returning
to its famous first sentence one appreciates
the depths of its intension.</p>
</doc>

<xsl:template name="element">
 <xsl:text>node(</xsl:text>
 <xsl:value-of select="generate-id(.)"/>
 <xsl:text>, element(</xsl:text>
 <xsl:value-of select="name()"/>
 <xsl:text>)).&#xA;</xsl:text>
 <xsl:choose>
    <xsl:when test="../..">
     <!--* when we have a parent which has a parent, say who it is *-->
     <xsl:text>parent-child(</xsl:text>
     <xsl:value-of select="generate-id(..)"/>
     <xsl:text>, </xsl:text>
     <xsl:value-of select="generate-id(.)"/>
     <xsl:text>).&#xA;</xsl:text>

     <xsl:text>path(</xsl:text>
     <xsl:value-of select="generate-id(.)"/>
     <xsl:text>,[</xsl:text>
     <xsl:number level="multiple" count="*" format="1,1" />
     <xsl:text>,</xsl:text>
     <xsl:value-of select="position()" />
     <xsl:text>]).&#xA;</xsl:text>

    </xsl:when>
    <xsl:otherwise>
     <!--* when we have a parent which is an element, say who it is *-->
     <xsl:text>document-element(</xsl:text>
     <!--* <xsl:value-of select="./@id"/> *-->
     <xsl:value-of select="generate-id(.)"/>
     <xsl:text>).&#xA;</xsl:text>
    </xsl:otherwise>
 </xsl:choose>
 <xsl:text>&#xA;</xsl:text>
 <xsl:for-each select="@*">
  <xsl:call-template name="attribute"/>
 </xsl:for-each>
</xsl:template>

node(n1, element(doc)).
path(n1,[1]).

attr(n1, lang, "en").
node(n3, pcdata("
")).
path(n3,[1,1]).
node(n4, element(p)).
path(n4,[1,1,2]).

node(n5, pcdata("Wittgenstein wrote:
")).
path(n5,[1,1,1]).
node(n6, element(q)).
path(n6,[1,1,1,2]).

attr(n6, lang, "de").
node(n8, element(ital)).
path(n8,[1,1,1,1,1]).

node(n9, pcdata("Die Welt ist alles,
was der Fall ist.")).
path(n9,[1,1,1,1,1]).
node(n10, pcdata("
It is hard to escape, at first reading,
the suspicion that Wittgenstein is guilty
here of a gross platitude; it is only
after reading the rest of the
")).
path(n10,[1,1,3]).
node(n11, element(title)).
path(n11,[1,1,2,4]).

attr(n11, lang, "la").
node(n13, pcdata("Tractatus")).
path(n13,[1,1,2,1]).
node(n14, pcdata(" that on returning
to its famous first sentence one appreciates
the depths of its intension.")).
path(n14,[1,1,5]).
node(n15, pcdata("
")).
path(n15,[1,3]).

<attribute match="@lang">
<doc>
<p>If an element has a <ident>lang</ident> 
attribute, the attribute value names the 
language of the element's content (unless 
overridden).</p>
</doc>
<rule distributed="true" lang="Prolog">
lang(<de xv="../@id"/>,.) :- !.
</rule>
<doc>
<p>Otherwise, the language is the same as that 
of the parent element.</p>
</doc>
<rule distributed="false" lang="Prolog">
lang(E,L) :- parent(P,E), lang(P,L).
</rule>
</attribute>

• by including appropriate inference rules in Prolog
• by including appropriate inference rules in XSLT

lang(E,L) :- parent(P,E), lang(P,L).

<xsl:template name="calc-lang">
lang(
  <xsl:value-of select="generate-id(.)"/>
 ,
  <xsl:call-template name="inherit-lang"/>
).
</xsl:template>

<xsl:template name="inherit-lang">
 <xsl:choose>
  <xsl:when select="@lang">
   <xsl:value-of select="@lang"/>
  </xsl:when>
  <xsl:otherwise>
   <xsl:for-each select="..">
    <xsl:call-template name="inherit-lang"/>
   </xsl:for-each>
  </xsl:otherwise>
 </xsl:choose>
</xsl:template>
<!--* can you find the bug here? *-->

• ontology (what does this mean?)
• is completeness achievable? is it a goal?
• housekeeping problems
• the tenacious agnosticism of TEI

• the element (in this encoding)
• the text (= this rule asserts that in the text there is some (component?) part which is represented by this XML element in this encoding, and that that component has some property.
• some referent of the text
• some other encoding or representation of the text
• the words or characters contained* (except for notes, etc.) within this element (but N.B. deletions, insertions)

• the element (This TEI header was last updated 2001-06-15.)
• the text (This work [i.e. Peer Gynt] was created in 1874)
• some referent of the text (Henrik Ibsen was born in ...)
• the words or characters contained in this element (The string "Ibsen" is a proper noun here — not the name element)
• some other encoding or representation of the text (A page-break occurs at this point in the edition of 1874)

• complete formalized-TSD for TEI Lite
• create formalized-TSD for some other DTDs
• refine DTD for formalized-TSD
• experiment with calculation of non-immediate inferences (a) in XSLT, (b) in inference engine — what are the tradeoffs, really?
• experiment with retrieval and other applications
• theorize the whole enterprise