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Re: D7 - Which languages are better than OWL?

Title:
    Dear Philippe,

    Apparently, you have some problems in catching my central point, which is very simple. Independently then from any representational trick, from RDF to FCG or other, this point is that, in an n-ary situation like that represented by the event "Mary has given a book to Bill", you are surely entitled to decompose this situation in a series of binary relationships, saying, e.g., that Mary is the subject of an action of giving but, in order to "understand" really this elementary event, you must necessarily merge again the single binary relationships in a global unit, (an n-ary one), and to work on this in a global way. If you deal with the elementary binary relationships separately (this is what the W3C languages allow at the moment), it is difficult you will ever be able to move beyond the inferences of the "uncle" type the SWRL's supporters are fond of.

    In NKRL, an event like the above is represented as an instance of a general, n-ary "template" of the type "Move:TransferMaterialThingToSomeone", which is a specialization of a  "Move:TransferToSomeone" template. In the two templates (and in their instances) the semantic predicate is (conventionally) MOVE, and the slots SUBJ, OBJ and BENEFICIARY are necessarily filled; the other (MODAL, CONTEXT etc.) can be filled or not depending from the original formulation of the event. In the concrete instances, the temporal information must obviously be added. All the inferences are then executed starting from this unitary, n-ary block. Note, moreover, that I have voluntarily chosen a particularly simple example, avoiding, e.g., to speak of "connectivity phenomena" in the style of "Mary has given a book to Bill BECAUSE it was Bill's birthday".
   
    There are some other strange statements in your mail, like "... the primitive notion here is the concept type Gift, not the relation types gift etc." (???) but, as you suggest, I will reply, in case, separately (but only when my book will be finished).

    Regards,

    GPZ



 



mail@PHILIPPEMARTIN.COM wrote:



  
Dear Gian,

  

  

    
"a representation using an n-ary relation can always be converted
 to a representation using a binary relation, without loss of
 semantics" ... "without loss of semantics" is false.
    

  

  

I was waiting/hoping for that feedback.
Unfortunately, I am missing the (fine) point(s) in both your
email and the article you cited:
1) Where is the loss of semantics when you translate
     (giftOfSomethingBySomeoneToSomeoneSometime 
            book328    Mary128  Bill948 '12/9/2007')
   into (I use the FCG notation here)
         [a Gift, object: book328, agent: Mary128,
                  recipient: Bill948, date:12/9/2007]
   or to [ [a Gift, object: book328, agent: Mary128,
                    recipient: Bill948], date:  12/9/2007]
   I only see an increase of precision/semantic because
   the roles have been explicited. As you acknowledge in
   our article this decomposition avoids the combinatorial
   explosion of relation types such as 
   giftOfSomethingBySomeoneToSomeoneSometime, which
   furthermore cannot be ordered into a specialization 
   hierarchy (thus making knowledge re-use and comparison
   difficult). I'd add the fact that you can quantify the
   concept type 'Gift' (e.g., "2 Gift"or "any Gift") but not
   the previous relation type. Hence, I think the primitive
   notion here is the concept type Gift here, not the relation
   types gift or giftOfSomethingBySomeoneToSomeoneSometime.
2) At the end of page 3 of your article, you hint at the
   n-ary nature of the anonymously referred situation instance
   (in my above example, the particular gift , say,
    gift739ofSomeBookFromMary128ToBill948AtDate12/9/2007).
   I personally see this instance as an instance of the 
   concept type Gift, not as an instance of an n-ary relationship
   but, in any case, what are the consequences (where is the
   loss of semantics)?
3) what are these inferences that must "NECESSARILY" be made in NKRL
   even though NKRL can be fully translated from and to RDF?
   (I actually only saw binary relations in the NKRL examples
   of your article but I admit I have not yet read Section 3
   in detail). Please use an example, preferably using KIF or FCG.
  
Given we are here departing a bit from the core goal of D7, it might
be better to answer to me directly and I'll then post a summary of 
the underlying ideas in my structured format (when I understand 
these ideas enough to give a good summary). I let you be judge.

Philippe