Re: Is it a redundancy? Indetected inconsistency?

Hi,Thanks  for your answer.I just want to try an example (in the framework of my phd) and check if it introduces even unsatisfiable classes (I was wrong, the ontology was consistent but incoherent). Sorry for the example which isn't relevant to reality.Another response for my question is I have detected that I have to cancel the introduction of subClassOf (person ObjectUnionOf(woman man) before the addition of the other one.please, have you an idea about approaches , technics in litterature that control the introduction of such irrelevant examples w.r.t to the reality.(avoiding having non pertinent axioms which are semantically (w.r.t to the modeled domain) incorrect but logically correct since reasoner doesn't detect any inconsistency or incoherency)Thank you very much for answers. 

     Le Mardi 10 mars 2015 4h20, Pat Hayes <phayes@ihmc.us> a écrit :
   

 I am trying to make sense of your axioms, but they do seem rather odd. Comments in-line.

On Mar 9, 2015, at 7:43 PM, Leila Bayoudhi <bayoudhileila@yahoo.fr> wrote:

> Hi,
> Having already:
> subClassOf(person animal)
> DisjointClasses(woman animal )

What is your intention with these axioms? On the face of things they seem rather confused. If people are animals, why would women *not* be animals? This is technically consistent, but only by not having women be people, which is hardly a politically correct view of the fairer sex, and in any case you treat men in the same way:

> DisjointClasses(man animal)

So now anything in the classes man or woman cannot be an animal, so cannot be a person. Is this what you intended?

> 
> We want to introduce subClassOf (person ObjectUnionOf(woman man)
> This may introduce inconsistency.

It should not, since these are consistent. For example, if all the classes man, woman and person are the empty class, then all four sentences are true (since the empty class is a subclass of any class.) So they do have a satisfying interpretation, albeit one which describes a rather grim view of things, in which human beings are extinct. 

> So, we choose as a solution to  introduce a subClassOf (person ObjectUnionOf(animal ObjectUnionOf(woman man)).

That is also true under the no-people interpretation, since the empty class is a subclass of its union with itself.

> 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): Is it correct what i am saying?

I really don't quite know what you are saying, to be honest. Your axioms are all consistent, but they do not make intuitive sense, unless you are trying to say that there aren't any people; but then why bother to introduce the men and women classes?

Can you write out  just in plain English sentences what it is that you are intending to say? 

Pat Hayes

> 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).
> 
> Thx for answering me those questions?
> 
> 

------------------------------------------------------------
IHMC                                    (850)434 8903 home
40 South Alcaniz St.            (850)202 4416  office
Pensacola                            (850)202 4440  fax
FL 32502                              (850)291 0667  mobile (preferred)
phayes@ihmc.us      http://www.ihmc.us/users/phayes