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rdfowlsemantic-webprotegerdfs

Inference on Complex Classes in Protege

I want to make inferences such as the property represented by the grey-dotted line in this diagram:

kale goes well with pear because it tastes bitter which complements pear's sweet

I have asserted a general axiom:

(hasTaste some Bitter) SubClassOf: goesWellWith some (hasTaste some Sweet)

where 'bitter' is of type Bitter and 'sweet' is of type Sweet.

I thought owl:someValuesFrom (or Manchester's "some") meant that at least one such relation must exist. Yet this does not happen after making the bold diagram assertions and the general axiom.

How can I make this work?

EDIT (Edit 2, I figured it out)

I just thought of a super-property chain that works! I just specify

hasTaste o complements o isTasteOf

as a super property chain of goesWellWith. In fact, by making hasTaste, hasTexture, etc...all sub-properties of of a general hasTrait, then I can replace hasTaste and isTasteOf with hasTrait and isTraitOf, respectively:

hasTrait o complements o isTraitOf

The result captures every permutation of food properties complementing each other.

enter image description here

Solution

  • In answering you question I will (1) explain why your approach fails and (2) provide a possible solution.

    Why your approach fails

    Reasoners in genereal only give feedback on inferences based on named classes, not anonymous classes. In your example (hasTaste some XXX) and goesWellWith some (hasTaste some YYY) are anonymous classes and therefore they will in general not form part of the reported inferences of a reasoner.

    A possible solution

    ObjectProperty: hasIngredient
    Characteristics: Transitive
    Domain: 
        FoodCombination    
    Range: 
        Food       

ObjectProperty: hasTaste
    SubPropertyChain: 
        hasIngredient o hasTaste
    Characteristics: 
        Transitive
    Domain: 
        Food
    Range: 
        Taste

Class: Bitter
    SubClassOf: 
        Taste

Class: BitterSweetCombination
    EquivalentTo: 
        (hasTaste some Bitter)
         and (hasTaste some Sweet)
    SubClassOf: 
        TastyCombination

Class: CulinaryDish
    SubClassOf: 
        FoodCombination

Class: DespicableCombination
    SubClassOf: 
        FoodCombination

Class: Food
    DisjointWith: 
        Taste

Class: FoodCombination
    SubClassOf: 
        Food
    DisjointUnionOf: 
        DespicableCombination, TastyCombination

Class: Kale
    SubClassOf: 
        Food,
        hasTaste some Bitter
    DisjointWith: 
        Pear

Class: Pear
    SubClassOf: 
        Food,
        hasTaste some Sweet
    DisjointWith: 
        Kale

Class: PearKaleDelight
    SubClassOf: 
        CulinaryDish,
        hasIngredient some Kale,
        hasIngredient some Pear

Class: Sweet
    SubClassOf: 
        Taste

Class: Taste
    DisjointUnionOf: 
        Bitter, Sweet
    DisjointWith: 
        Food

Class: TastyCombination
    SubClassOf: 
        FoodCombination

    This ontology will classify the PearKaleDelight class as being a subclass of BitterSweetCombination.