Re: Is it a redundancy? Indetected inconsistency?

On 10 Mar 2015, at 14:08, Leila Bayoudhi <bayoudhileila@yahoo.fr> wrote:

> Hi,
> Thanks all for your answers. 
> The proposed solution is taken from ontology design patterns site .

I cannot say that I find the description there particulalyr perspicuous. 

> As the attached figure shows:
>  subClassOf( Carnivorous_plant unionOf(animal, plant)) and we already have subClassOf(Carnivorous_plant  , plant)

Ok. I don’t think this is what the pattern meant, as that is silly (because redundant).

I think that this is the transform:
Original ontology:
 Animal ⊑Fauna-Flora, 
 Plant ⊑Fauna-Flora, 
 Carnivorous-Plant ⊑Plant, 
 Plant ⊑ Not(Animal)
new ontology:
 Animal ⊑Fauna-Flora, 
 Plant ⊑Fauna-Flora, 
 Carnivorous-Plant ⊑(Plant or Animal), 
 Plant ⊑ Not(Animal)

The solution:
 Animal ⊑Fauna-Flora, 
 Plant ⊑Fauna-Flora, 
 Carnivorous-Plant ⊑Plant, 
 Carnivorous-Plant ⊑(Plant or Animal), 
 Plant ⊑ Not(Animal)
is pointless as it’s equivalent to the original ontology.

BTW, this is a terrible pattern for this case. What this tells us is that (potentially) *some carnivorous plants are animals and thus not plants*. But that’s surely not the intent! 

Frankly, I don’t know why anyone would want carnivorous plants to be animals :), but presumably the idea is that they are animalesque plants, not that there are some that are non-plants.

Now perhaps somewhere you have that all carnivores are animals. That *would* be a problem, but the solution is obvious *in that case* and is in fact this pattern.

> Does this at end means that  subClassOf(Carnivorous_plant plant)   (this is according to the reasoner since subClass(A B) subclass(A C) ==> subClass(A intersectionOf(B C)).
> So is this solution correct? or does it propose a redundant axiom?
> Thanks for answering me.
>  
> 
> 
> Le Mardi 10 mars 2015 9h25, Bijan Parsia <bijan.parsia@manchester.ac.uk> a écrit :
> 
> 
> On Mar 10, 2015, at 0:47, "Leila Bayoudhi" <bayoudhileila@yahoo.fr> wrote:
> 
>> Hi,
>> Having already:
>> subClassOf(person animal)
>> DisjointClasses(woman animal )
>> DisjointClasses(man animal)
>> 
>> We want to introduce subClassOf (person ObjectUnionOf(woman man)
>> This may introduce inconsistency.
> 
> No but it does introduce in satisfiability. 
> 
>> So, we choose as a solution to  introduce a subClassOf (person ObjectUnionOf(animal ObjectUnionOf(woman man)).
> 
> But this is not helpful if you have the original axioms. Ie they are equivalent. 
> 
>> According to protegé, the ontology is no longer inconsistent. However, it seems as if the ontologist wants at the end to say that:
>> subClassOf (person ObjectUnionOf(woman man):
> 
> If you preserve the original axioms, then there will still be no person who is either a man or a woman. 
> 
>> Is it correct what i am saying?
>> If it is not: is it problem of my proposed solution for maintaining consistency?
>> Am I introducing redundant axioms(though OWL 2 DOES NOT care for this, I care).
> 
> Without the union with animal, person is unsat. 
> 
> With the union with animal, the new axiom is redundant. 
> 
>> Thx for answering me those questions?
>> 
>> 
> 
> 
> <Djedidi_LOP2_WOP09.pdf>