I was wondering if you could clear this up, specifically wrt what you intend by "necessary"
So, statements like "The United States are a country" or "The United States have a president" may perfectly go, say, in a eGov ontology. On the contrary, a statement like "The present president of United States is Barack Obama", should not go in an ontology (the Tbox), it rather goes to the Abox, simply because it doesn't hold necessarily.
For example, that "the United States is a country" seems necessary given the existence of the United States. And by necessary I mean something like
(w)(t)[E(us,<w,t>) -> Country(us,<w,t>)]
where w is a world and t a time and E an existence predicate. Of course a separate discussion would be needed about what the accessibility relation looks like for worlds and times. In the case of Obama, we'd have something like
E(obama,<@,now>) & President(obama,us,<@,now>)
Where @ is the actual world. So, Obama is contingently president at this time.
But if this is true would it not be necessary, wrt this (actual) world and time that Obama is president for his term?
In sum, I sympathize with your intuition, but it would take some work to pin it down precisely.
Cheers
.bill
Bill Andersen
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