On Tue, Apr 18, 2017 at 3:22 PM, Alex <[email protected]> wrote:
> Maybe we can solve the problem about modelling classes (and using OO and > UML notions for knowledge representation) with the following (pseudo)code > > - We can define ConceptNode "Object", that consists from the set or > properties and functions > > - We can require that any class e.g. Invoice is the inherited from the > Object: > IntensionalInheritanceLink > Invoice > Object > > - We can require that any more specifica class, e.g. VATInvoice is the > inherited from the more general class: > IntensionalInheritanceLink > VATInvoice > Invoice > > - We can require that any instance is inherited from the concrete class: > ExtensionalInheritanceLinks > invoice_no_2314 > VATInvoice > If you wish, you can do stuff like that. opencog per se is agnostic about how you do this, you can do it however you want. The proper way to do this is discussed in many places; for example here: https://en.wikipedia.org/wiki/Upper_ontology I'm not particularly excited about building ontologies by hand, its much more interesting (to me) to understand how they can be learned automatically, from raw data. > > But I don't know yet what can and what can not be the parent for > extensional and intensional inheritance. Can an entity be extensionally > inherited from the more complex object or it can be extensionally inherited > from empty set-placeholder only. When we introduce notion of set, then the > futher question always arise - does OpenCog make distinction between sets > and proper classes? > Why? This "distinction" only matters if you want to implement set theory. My pre-emptive strike to halt this train of thought is this: Why would you want to implement set theory, instead of, say, model theory or universal algebra, or category theory, or topos theory? why the heck would distinguishing a set-theoretical-set from a set-theoretical-proper-class matter? (which oh by the way is similar but not the same thing as a category-theoretic-proper-class...) You've got multiple ideas going here, at once: the best way to hand-craft some ontology; the best theoretical framework to do it in; the philosophy of knowledge representation in general... and, my personal favorite: how do I get the machine to do this automatically, without manual intervention? > > There is second problem as well - there is only one - mixed > InheritanceLink. One can use SubsetLink for the extensional inheritance > (still it feels strange), but there is certainly necessary syntactic sugar > for intensional inheritance, because it is hard to write and read > SubsetLink of property sets again and again (http://wiki.opencog.org/w/ > InheritanceLink). > If the machine has learned an ontology with a million subset links in it, no human being is ever going to read or want to read that network. It'll be like looking at a bundle of neurons: the best you can do is say "oh wow, a bundle of neurons!" --linas > > -- > 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/a6d0102e-9ca1-4204-8dd4-75a9fb2ec06b%40googlegroups.com > <https://groups.google.com/d/msgid/opencog/a6d0102e-9ca1-4204-8dd4-75a9fb2ec06b%40googlegroups.com?utm_medium=email&utm_source=footer> > . > > 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/CAHrUA34p%3DcvtXtrkBpewTu1mTP96Hyqv7qVsJ27TkZyGqwz8sQ%40mail.gmail.com. For more options, visit https://groups.google.com/d/optout.
