Fwd: Re: Implicit Quantification in N3

Hello,
Sorry for sending an unfinished mail! Here the entire mail:

first of all: Thank you for your answers!
I still have two remarks/questions:


>> I am currently trying to write down the basic formal semantics of N3 and I had some problems with implicit quantification. Maybe you could help me here?
>>
>> I am not 100% sure how the scope of the universal quantifiers is. If I have for example the formula:
> They are universally quantified in the graph one outside the one they are mentioned in.  This is to
> get simple rules to work like sparql.
1. I am a little bit confused here, I thought that sparql handles that 
case different.  If I have the query:

    select distinct ?p ?t where {

     {{{?p a<http://dbpedia.org/ontology/Place>.}}}

     {{{?t<http://xmlns.com/foaf/0.1/primaryTopic>  ?p. }}}

    }




Doesn't it mean the same as:

    select distinct ?p ?t where {

     {?p a<http://dbpedia.org/ontology/Place>.}

     {?t<http://xmlns.com/foaf/0.1/primaryTopic>  ?p. }

    }




So here the scope of the quantification seems to be on top level and not 
just on the "mother-graph". This is different than in the n3-example I 
posted earlier. But maybe I just misunderstood you?


>   
>>     {{?x :p :o}=> {?x :pp :o}}=> {{?x :g :l}=>{?x :k :o}}.
>>
>> Are the four ?x the same?
> No, the first two are the same and the second two are.
>
> If in doubt use @forAll
>
2. I started with with a formalisation which uses @forAll but I got 
problems with formulas such as:

 { @forAll :x. :x :p :o.} => {:x :pp :o}.


Does the scope of the @forAll end with the bracket "}"?


Thank you in advance for your explanations and opinions!

Greetings,
Dörthe Arndt


-- 
Dörthe Arndt
Researcher Semantic Web
Ghent University - iMinds - Multimedia Lab
Faculty of Engineering and Architecture
Department of Electronics and Information Systems
Gaston Crommenlaan 8 bus 201, B-9050 Ledeberg-Ghent, Belgium

t: +32 9 331 49 59
e:dorthe.arndt@ugent.be
URL:http://multimedialab.elis.ugent.be