Re: General semantics
Date: Fri, 21 May 2010 04:38:26 -0700 (PDT)
On 21 mei, 12:45, Nilone <rea..._at_gmail.com> wrote:
> On May 21, 7:57 am, Clifford Heath <n..._at_spam.please.net> wrote:
> > paul c wrote:
> > > By unary relation I mean a relation with one attribute (which I think is
> > > pretty standard lingo, surprised that anybody here wouldn't think that)
> > Right, that's what I thought you meant. In which case, it could be a
> > representation of either an existential fact type (an object type),
> > or a unary predicate over one. The distinction is important. A unary
> > predicate creates a subset of the object type it involves.
> > This distinction was, I believe, the cause of your earlier disagreement.
> > Further, a unary fact type does not have to be mapped as a unary relation.
> > It could be represented as a boolean value in a table of that object type.
> > > but I have no idea what a 'fact type' is. I know of relation and tuple
> > > types but don't know what use terms like 'fact type' or 'unary fact'
> > > terms might have.
> Perhaps, fact type = intension while unary fact = proposition
Instantiating a predicate with attribute values always yields a proposition, no matter what the degree of the relation is. Received on Fri May 21 2010 - 13:38:26 CEST