[foaf-dev] Re: RDF triple assertions live forever?

[Phil Archer]

Being the one who kicked this off by making the original assertion 
(which I actually got from someone else but almost certainly 
mis-interpreted along the way) I feel I should give a little further input.

Actually, it's _good news_ (as well as common sense) that triples don't 
get stored in perpetuity. I came to this from the standpoint of wanting 
to make the statement (in a semantic way) that

foaf:Agent "will stand by the following assertions until" $date

Which is a little different from a cache header...

Phil.

Renato Golin wrote:
> 
> Phillip Rhodes wrote:
>> In a discussion that has arisen recently on the foaf-dev list, somebody
>> pointed out that they've been told that RDF triples live forever.  
>> That is, once something is asserted it is considered asserted until, 
>> as it
>> was put, "the entropic heat death of the universe."
> 
> Hi Phillip,
> 
> This assertion is, to me, the same as to say all web pages are static, 
> meaning that you can cache them locally without any further attempt to 
> get it back from the server again.
> 
> All web browsers have a fair cache policy which we're all used to 
> (Shift-F5 and stuff) so no big deal to do the same with triples and RDF 
> browsers.
> 
> Also, with RDF is easier to say that site A has "the same triple as" 
> another site B but with different content, who will you trust? Let's say 
> you have a timestamp annotating the triples, would you still believe the 
> "newest" one?
> 
> Site A:
>   renato is bad (today)
> 
> Site B:
>   renato is good (10 years ago)
> 
> It's the same with RDFAuth, you have to trust someone sometime, you need 
> a list of trusted sites, people, documents, beliefs. If your site says 
> "renato is bad" it may "like" better Site A and even automatically add 
> it to the "trusted sites" or even keep a score of things you agree with 
> the site as the "automatic trust level" as opposed to your "hardcoded 
> trust level" when you trust someone even if you don't agree with him/her.
> 
> The possibilities are endless...
> 
> cheers,
> --renato
> 
> 
> 

-- 
Phil Archer
Chief Technical Officer,
Family Online Safety Institute
w. http://www.fosi.org/people/philarcher/