Formulas are just sets of triples, so we can test for what is not contained.
If someone's page does not say they are vegetarian, let's assume they are an omnivore:
this log:forAll :x. {:x :homePage log:notIncludes { :x a :Vegetarian }} => { :x a :Omnivore }.
Of course, using defaults like this often gives wrong results
...but sometimes it's still your best option.
4 of 17 |