OK, so ... On Fri, Jun 17, 2016 at 6:35 AM, 'Nil Geisweiller' via opencog < [email protected]> wrote:
> Ben, Amen, > > On 06/17/2016 08:22 AM, Ben Goertzel wrote: > >> Nil, Linas, etc., >> >> Amen suggested an alternate approach to representing embedded truth >> values, which may be better than our previous suggestions, due to >> reusing ContextLink rather than introducing additional mechanisms... >> see >> >> >> http://wiki.opencog.org/wikihome/index.php/Claims_and_contexts#An_Alternate_Approach >> > > I read a whole page. But I don't understand, what is the domain of > > SatisfyingSet > $X > Evaluation > hope > Aaron > $X > > ? > > I mean what are the $Xs? > The $Xis can be anything at all, the entire universe of all things. More narrowly, the satisfying set is true only if $X is a thing that Aaron hopes. Of course, we don't know what those things might be, at least, not yet. > I would assume that they are > > Evaluation eat@456 Ben lunch > That would indeed be one thing that Aaron hopes. > > etc. > > But then why do you use a ContextLink? Wouldn't that be instead > > MemberLink > SatisfyingSet > $X > Evaluation > hope > Aaron > $X > Evaluation eat@456 Ben lunch > I guess that could work. At the time that the wiki page was created, MemberLink was not fashionable. Now its fashionable again, so I guess that's OK. > Or > > Inheritance > SetLink > Evaluation eat@456 Ben lunch > SatisfyingSet > $X > Evaluation > hope > Aaron > $X > ? > That seems reasonable too. > > Also I would think that since eat@456 is a particular instance, then it > suffices to restrict the knowledge around it, so again why a context link? > I'm not sure that there is any strong reason, but let me try to sketch some of the original reasoning: MemberLinks and InheritanceLinks assert facts, relationships that are true "globally", in the universe as a whole. ContextLinks assert facts, relationships that are true only in Aaron's mind. This goes back to the old question of how to map Kripkle frames into the atomspace. There are many different confusing things written about Kripke frames; the particular variant that I like to think about is that which is called a "microtheory" in CYC -- a set of self-consistent statements that are true at a particular location during chaining. So, during forward chaining, you start with one single "context" or "set of facts". At each step of chaining, you get a new, slightly larger set of facts: the original ones, plus whatever you have deduced. This is a "Kripke frame". Note that two instances of the same chainer, if they start with the same initial context, but select something else to "think about", will deduce a different set of facts, and start on a path down a different set of frames or "mini-universes". Some of these different deduction paths may contradict one-another (for example, consider evidence in a legal case), and some of these paths converge to the same total set of conclusions. The idea here is that a kripke frame or a context or a min-universe holds things that are known to be true at a certain point of of a history-path of deduction. The mini-universe of things that Aaron thinks is just another context. That's how it got to be Context, and not something else. I hope you see how MemberLinks are inappropriate for the kripke frames (I think !?), but they might be fine for what Aaron thinks. If not, then I'm not sure what the point of Context links really is. --linas > Thanks, > Nil > > >> -- Ben >> >> > -- > You received this message because you are subscribed to the Google Groups > "opencog" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to [email protected]. > To post to this group, send email to [email protected]. > Visit this group at https://groups.google.com/group/opencog. > To view this discussion on the web visit > https://groups.google.com/d/msgid/opencog/5763E071.80606%40gmail.com. > > For more options, visit https://groups.google.com/d/optout. > -- You received this message because you are subscribed to the Google Groups "opencog" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. To post to this group, send email to [email protected]. Visit this group at https://groups.google.com/group/opencog. To view this discussion on the web visit https://groups.google.com/d/msgid/opencog/CAHrUA37y763hnv7sYuk4RfjaEdwJMEcV8wxqcb5-F_nSJiHtAQ%40mail.gmail.com. For more options, visit https://groups.google.com/d/optout.
