Example Problem

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%----All (hu)men are created equal. John is a human. John got an F grade.
%----There is someone (a human) who got an A grade. An A grade is not 
%----equal to an F grade. Grades are not human. Therefore there is a 
%----human other than John.

fof(all_created_equal,axiom,(
    ! [H1,H2] : ( ( human(H1) & human(H2) ) => created_equal(H1,H2) ) )).

fof(john,axiom,(
    human(john) )).

fof(john_failed,axiom,(
    grade(john) = f )).

fof(someone_got_an_a,axiom,(
    ? [H] : ( human(H) & grade(H) = a ) )).

fof(distinct_grades,axiom,(
    a != f )).

fof(grades_not_human,axiom,(
    ! [G] : ~ human(grade(G)) )).

fof(someone_not_john,conjecture,(
    ? [H] : ( human(H) & H != john ) )).

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