On Fri, Nov 13, 2015 at 8:34 PM, And Rosta <[log in to unmask]> wrote:
>
>
> On 13 November 2015 at 18:30, Lukasz Stafiniak <[log in to unmask]> wrote:
>>
>> Hi And,
>>
>> Does it in effect mean that the underlying data structure are triples
>> (A, C, R) such that A isa C? A relationship A--B would be built out of
>> two triples (A, C, R) and (B, D, R).
>
>
> I'll first restate what I've written in my previous:
>
> Given A--R--B, to know that A' isa A and B' isa B, and that A'--R'--B' is to
> know that R' isa R. You know that R' isa R iff you know that A' isa A and B'
> isa B, and that A'--R'--B'.
> But that's only if R' is relational. It must also be possible that
> nonrelational X isa R.
If as you said relations are never unclassified, then the triple
notation works. (The triple notation is very friendly to N-ary
relations, which may be bad if in fact relations are binary.)
(1) Can a relation have a single role? E.g. A -sibling-sibling- B;
alternative notation (A, sibling, R'), (B, sibling, R'), R' isa
siblinghood.
(2) What is on higher levels / at the top of the hierarchy /
hierarchies? Using my notation: (sibling, living-being, siblinghood),
siblinghood isa genealogical-relation, (living-being, living-being,
genealogical-relation), genalogica-relation isa relation, (thing,
thing, relation)...
Alternatively (sibling, family-member, siblinghood), siblinghood isa
family-relation, (family-member, person, family-relation),
family-relation isa social-relation, (person, person,
social-relation)...
Thanks!
Lukasz
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