Re: Decision from the Semantics TF: liberal baseline

On 08/01/2025 18:29, Franconi Enrico wrote:
> SMART. I like it. 

I like it too, this is very elegant, but...

the proposed entailment patterns are mixing RDF and RDFS entailment.

If we follow the current "layering",  reif1 / reif2 would NOT produce 
the following triples in RDF-entailment (not RDFS)
     xxx rdf:type rdfs:Resource
     zzz rdf:type rdfs:Resource
and therefore, Niklas' trick does not work anymore :-(

Now, we may decide that "everything is a Resource" should belongs to 
RDF-semantics after all (rather than only RDFS), and that would solve 
the problem -- at the cost of destroying the last bit of consistency in 
the rdf:/rdfs: namespace split! :->.

> —e.
>
>> On 8 Jan 2025, at 18:26, Doerthe Arndt <doerthe.arndt@tu-dresden.de> 
>> wrote:
>>
>>
>>
>>> Am 08.01.2025 um 18:14 schrieb Franconi Enrico <franconi@inf.unibz.it>:
>>>
>>> With this in mind:
>>>
>>>
>>>  if the triple structure appears in S  then S RDF(S) entails
>>> */reif0/*  sss aaa ooo  sss rdf:type rdfs:Resource .
>>> ooo rdf:type rdfs:Resource .
>>> aaa rdf:type rdf:Property .
>>> */reif1/*  sss aaa <<(xxx yyy zzz)>>  <<(xxx yyy zzz)>> rdf:type 
>>> rdfs:Proposition .
>>> */reif2/*  <<(xxx yyy zzz)>> aaa ooo  <<(xxx yyy zzz)>> rdf:type 
>>> rdfs:Proposition .
>>> */reif3/*  sss rdf:reifies ooo  ooo rdf:type rdfs:Proposition .
>>>
>>>
>>> On 8 Jan 2025, at 18:07, Doerthe Arndt <doerthe.arndt@tu-dresden.de> 
>>> wrote:
>>>
>>>> General:
>>>> - Niklas made an interesting point: If you  derive from
>>>>> sss aaa <<(xxx yyy zzz)>>
>>>>>
>>>> that
>>>> xxx a rdfs:Resource. and zzz a rdfs:Resource.
>>>> then we do not need the  „if the triple structure appears in S“ for 
>>>> rdf:Resource and can stick to „if S contains“.
>>>
>>> What if this triple structure is deeply embedded?
>>
>>
>> I propose an alternative (based on Niklas idea):
>>
>>
>>>
>>>  if  S contains  then S RDF(S) entails
>>> */reif0/*  sss aaa ooo  sss rdf:type rdfs:Resource .
>>> ooo rdf:type rdfs:Resource .
>>> aaa rdf:type rdf:Property .
>>> */reif1/*  sss aaa <<(xxx yyy zzz)>>  <<(xxx yyy zzz)>> rdf:type 
>>> rdfs:Proposition .
>>> xxx rdf:type rdfs:Resource.
>>> zzz rdf:type rdfs:Resource.
>>> yyy rdf:type rdf:Property.
>>> */reif2/*  <<(xxx yyy zzz)>> aaa ooo  <<(xxx yyy zzz)>> rdf:type 
>>> rdfs:Proposition .
>>> xxx rdf:type  rdfs:Resource.
>>> zzz rdf:type  rdfs:Resource.
>>> yyy rdf:type rdf:Property.
>>> */reif3/*  sss rdf:reifies ooo  ooo rdf:type rdfs:Proposition .
>>>
>>
>> If I now have
>>
>> s p <<(a b <<(x y z)>>)>>.
>>
>> I get with reif1:
>>
>> <<(a b <<(x y z)>>)>> rdf:type rdfs:Resource.
>>
>> But from that, I get with reif2:
>>
>> <<(x y z)>>  rdf:type rdfs:Resource.
>>
>> I can again apply reif2 and get:
>>
>> x a rdfs:Resource.
>> z a rdfs:Resource.
>> y a rdf:Property.
>>
>> Kind regards,
>> Dörthe
>>
>>>
>>> It seems I fixed your comment below with my latest proposal above.
>>> Comments welcome!
>>> —e.
>>>
>>>> Problem keeps being rdf entailment and the property.
>>>>
>>>> RDF:
>>>> - I guess aaa in reif1 and reif2 should be yyy?
>>>>
>>>> RDFS:
>>>> - we do not need
>>>>> <<(xxx yyy zzz)>> rdf:type rdfs:Resource .
>>>>>
>>>> in reif1 and reif 2 because we get that with the existing rules 
>>>> from RDFS.
>>>> We do need
>>>> xxx a rdfs:Resource.
>>>> and
>>>> yyy a rdfs:Resource.
>>>> instead.
>>>>
>>>>
>>>> Kind regards,
>>>> Dörthe
>>>>
>>>>
>>>>>
>>>>>
>>>>>> On 8 Jan 2025, at 17:35, Franconi Enrico <franconi@inf.unibz.it> 
>>>>>> wrote:
>>>>>>
>>>>>> Option 1 (the current option) adds metamodelling inference only 
>>>>>> for asserted triples.:
>>>>>>
>>>>>>
>>>>>>         Option 1 (shallow metamodelling)
>>>>>>
>>>>>>
>>>>>>           * ⏩ |<[I+A](r), [I+A](rdf:Proposition)> ∈
>>>>>>             IEXT([I+A](rdf:type))|
>>>>>>                       if |r is a triple term and ∃ x,y .
>>>>>>             (<x,[I+A](r)> ∈ IEXT(y)) ⋁ (<[I+A](r),x> ∈ IEXT(y))|
>>>>>>                       or if |∃ x . <x,[I+A](r)> ∈
>>>>>>             IEXT([I+A](rdf:reifies))| ⏪️
>>>>>>
>>>>>> Note that this is just wrong since in this case we have
>>>>>> [I+A](rdfs:Resource) ≠ IR
>>>>>> [I+A](rdfs:Property) ≠ IP
>>>>>>
>>>>>>
>>>>>>         Option 2 (true metamodelling)
>>>>>>
>>>>>>
>>>>>>           * ⏩ |<r, [I+A](rdf:Proposition)> ∈ IEXT([I+A](rdf:type))|
>>>>>>                       if |r ∈ range(RE)| or
>>>>>>                       if |∃ x,y . RE(x,[I+A](rdf:reifies),r)=y| ⏪️
>>>>>>           * ⏩ |<r, [I+A](rdfs:Resource)> ∈ IEXT([I+A](rdf:type))|
>>>>>>                       if |r ∈ range(RE)| or
>>>>>>                       if |∃ x,y,z . RE(x,z,r)=y| or
>>>>>>                       if |∃ x,y,z . RE(r,z,x)=y| ⏪️
>>>>>>           * ⏩ |<r, [I+A](rdfs:Property)> ∈ IEXT([I+A](rdf:type))|
>>>>>>                       if |∃ x,y,z . RE(x,r,z)=y| ⏪️
>>>>>>
>>>>>>
>>>>>> Option 2 adds new metamodelling conditions, which implies that
>>>>>>
>>>>>> [I+A](rdfs:Resource) = IR
>>>>>>
>>>>>> [I+A](rdfs:Property) = IP
>>>>>>
>>>>>> as it should.
>>>>>> The entailment pattern for option 2 will have "if the triple 
>>>>>> structure appears in S”.
>>>>>>
>>>>>> —e.
>>>>>>
>>>>>>> On 8 Jan 2025, at 17:17, Doerthe Arndt 
>>>>>>> <doerthe.arndt@tu-dresden.de> wrote:
>>>>>>>
>>>>>>> Dear Niklas,
>>>>>>>
>>>>>>>>
>>>>>>>> I think that it should be derived. And I agree that the triple 
>>>>>>>> constituents are resources (due to transparency).
>>>>>>>>
>>>>>>>> I believe the following rule does that (given the existing RDF 
>>>>>>>> 1.1 entailment):
>>>>>>>>
>>>>>>>> If S contains:
>>>>>>>>
>>>>>>>>   sss aaa <<(xxx yyy zzz)>> .
>>>>>>>>
>>>>>>>> or S contains (in symmetric RDF):
>>>>>>>>
>>>>>>>>   <<(xxx yyy zzz)>> aaa ooo .
>>>>>>>>
>>>>>>>> then S RDF(1.2)-entails (in symmetric RDF):
>>>>>>>>
>>>>>>>>   <<(xxx yyy zzz)>> rdf:type rdf:Proposition .
>>>>>>>>   <<(xxx yyy zzz)>> rdf:propositionSubject xxx .
>>>>>>>>   <<(xxx yyy zzz)>> rdf:propositionPredicate yyy .
>>>>>>>>   <<(xxx yyy zzz)>> rdf:propositionObject zzz .
>>>>>>>>
>>>>>>>> Then define:
>>>>>>>>
>>>>>>>> rdf:propositionPredicate rdfs:range rdf:Property .
>>>>>>>>
>>>>>>>> To make yyy a property. (Which I think makes sense, even though 
>>>>>>>> weird triple terms misusing e.g. classes as properties would 
>>>>>>>> have weird consequences.)
>>>>>>>>
>>>>>>>>
>>>>>>>
>>>>>>> It is a little bit more complicated because of the nesting. We 
>>>>>>> could have
>>>>>>>
>>>>>>> :a :b <<( :s :p  <<( :x :y :z )>> )>>.
>>>>>>>
>>>>>>> we would want to derive that
>>>>>>>
>>>>>>> :y a rdf:Property.
>>>>>>>
>>>>>>> But that could still be done with a detailed version of Enrico’s 
>>>>>>> "triple structure appears in“ notation. We could still get your 
>>>>>>> triples.
>>>>>>>
>>>>>>> Another problem I see with your approach here is that we depend 
>>>>>>> on RDFS while the properties are already derived in RDF and I 
>>>>>>> assume that we want to keep it that way.
>>>>>>>
>>>>>>> Another question is whether or not we want the proposition 
>>>>>>> subject, predicate and object, but they could serve the purpose.
>>>>>>>
>>>>>>> Kind regards,
>>>>>>> Dörthe
>>>>>>>
>>>>>>>
>>>>>>>
>>>>>>
>>>>>
>>>>
>>>>
>>>
>>
>