- From: Melvin Carvalho <melvincarvalho@gmail.com>
- Date: Sun, 15 Jan 2023 02:08:44 +0100
- To: angelo.veltens@online.de
- Cc: public-solid <public-solid@w3.org>, Henry Story <henry.story@gmail.com>
- Message-ID: <CAKaEYhKhX2mfkfH2wNTd608W-UMp6u2+BRE6+hsXd+FjGpRtqA@mail.gmail.com>
so 14. 1. 2023 v 8:19 odesílatel <angelo.veltens@online.de> napsal: > Thanks Henry , this is an important point to make. So having "copies" of > data like Ruben states it is actually not a problem, but a feature to > express different points of views of the world. I could have a birth date > in an official birth certificate, as well as in my address book and in my > list of birthdays. All of these documents can have different permissions > and different amounts of trust. It could even considered to be a feature > that I can be able to lie about a birthdate in one document, while I could > use the signed birth certificate in places where it matters. > > But still the practical problems for Solid app developers persist. When > does which app update what data? The brithday app and the contacts app > would write to different documents and the promise of data re-use is not > fulfilled. Perhaps the birthday app could have a feature to copy dates from > my contacts of I give the permission, but it all leaves the problem of > keeping data in sync that Ruben addresses. > In Solid different quads are different data Conversely the same quads are the same data Quad reuse is through client-client standards > > Kind regards > Angelo > > Sent from MailDroid <https://goo.gl/ODgwBb> > > -----Original Message----- > From: Henry Story <henry.story@gmail.com> > To: public-solid <public-solid@w3.org> > Cc: Melvin Carvalho <melvincarvalho@gmail.com> > Sent: Fr., 13 Jan. 2023 21:39 > Subject: Re: Detailed response to Ruben's blog > > Hi Melvin, > > Thanks for alerting us to this discussion. > > > On 12. Jan 2023, at 14:58, Melvin Carvalho <melvincarvalho@gmail.com> > wrote: > > > > IMHO, Insightful article on Solid architecture from TimBL. I found > myself agreeing. > > > > Worth a read. In particular, I liked this observation: > > > > "The Pod, in RDF terms, is a quadstore, not a triple store. A triples > store is not powerful enough. The 4th part of the quad, the ID of the > graph, we call a 'Document' to make it match with the way people talk. They > might be called Named Graphs or Linked Data Resources but "Documents" is > simpler. The fact that the ;inked data in a pod is basically a set of > distinct graphs is really important." > > > > https://www.w3.org/DesignIssues/2023/RubenBlogResponse.html > > > Yes, that is the key argument. Graphs stores are good for expressing one > perspective > on the world, one coherent point of view. Each new relation added to the > store > is one more monotonic fact added to the database. It brings with it the > view of truth > as a (maximal) database of facts. Pushed to the logical conclusion we end > up with a > possible world: the complete set of coherent facts about a world. > > But > 1. no person is perfectly consistent or knows everything > 2. the world is full of competing and cooperating agents > 3. truth is discovered by a dialogic process, of argument and > counterargument, > of asking for and giving reasons for one’s statement. > > So just that means we need ways to seperate perspectives, statements, ... > > In a plain graph database one can only deal with this inconsistency > by refusing to do reasoning. And indeed those databases don’t do > reasoning. > They could not, unless they enforced one oracle to manage the truth > of all statements. That could work for one organisations, but it > won’t for the world wide web. Just think of China, Russia, US, Saudi > Arabia, > Japan, Israel, Palestine, and all the other countries as agents, each of > which having very different interests and points of views. The world is > a multi-agent system since a billion years at least. > > A document is a statement of something by someone in a certain mode > (could be fictional mode or factual). The fourth element of our quads > is what is needed to name the result of the act of saying something. > The same graph produced in two different places is not the same saying, > and may have very different trust properties for example, even if they > have the same meaning. The statement by a doctor that I should take some > medication does not have the same value as someone in a bar telling me to. > > One can it is true accomodate multiple sayings in a graph database: > by turning the nodes for individual RDF graphs into a node of type > rdf:XMLLiteral with a content that would be an RDF/XML string. But the > nodes would be opaque to the reasoning of the rest of the graph, just as > named graphs in a quad store don’t interact, unless one asserts a number > of them to be true, or true in a world, or true in a point of view. > > Next. If we look at the naming hierarchy dimension of Ruben’s argument. > Oddly Ruben only mentions the placing of files on the file system and > the naming of those hierarchied but I did not see anything about following > links to find the data. This is the error made by the Web 2.0 APIs in > current > use: they set a fixed URL naming framework for placing data on the web, > instead of > working with a linked data ontology, where following links is the way to > find the data. In that case the location of the data is relatively > unimportant. That is what I thought HATEOAS was about [1]. > > Henry > > PS. > > * The original blog post by Verborgh is: > https://ruben.verborgh.org/blog/2022/12/30/lets-talk-about-pods/ > > * And thanks Melving for pointing to the archived version > > https://cloudflare-ipfs.com/ipfs/QmSB8WpxXAtd3Ny9G2ZsW39RJnRsfAt2X6Q7iNTGGWo9HE > > [1] https://en.wikipedia.org/wiki/HATEOAS > "Hypermedia as the Engine of Application State" > > > > > >
Received on Sunday, 15 January 2023 01:09:09 UTC