On Wed, Apr 9, 2008 at 6:03 AM, Stephen Reed <[EMAIL PROTECTED]> wrote: > > Thanks for the compliment Lukasz. I am reading your slides and here are my > comments: > > (1) I had seven years experience with the Cyc project. Would you agree > that Cyc aspires to be a KRS as you define it?
Well, as Hermann Helbig defines it. Yes, Cyc gets its highlight in the Multinet book. (I've only written a bit of text on the slides, most of them, the diagrams, come from the Multinet book.) > (2) Sadly, Cyc lacks procedural methods as first class KB objects. Also > known as codelets, these are pieces of procedural code that can be fired as > the consequent of a rule. Cyc has a facility to do this but the procedures > themselves are semantically opaque, being calls into the Cyc runtime engine. > In my own work I want to fully represent procedures, using Cyc action > scripts as the starting point, so that the system can "do things" in > addition to answering questions. Multinet doesn't help here much: QAS is not an agent; Multinet helps by providing the semantic framework for situations and actions. We need to add the representation of "self" "grounded" in that semantics. > (4) Conceptual Dependency Theory (CD) - This is somewhat like Cyc in that > Doug Lenat is a mathematician and was strongly attracted to symbolic > representations that are independent of natural language. The glaring > problem with this approach is that coverage of commonsense phenomena is > harder without guidance from natural language sources. To illustrate my > point, rather than start with an English encyclopedia and represent it > entirely, the Cyc project began with some commonsense situations, (e.g. one > day in the life of Fred) and represented them from first > philosophical/mathematical principles. In my own work, I want to extend > the Cyc ontology to cover all the concepts mentioned in the glosses > (definitions) of WordNet, and ultimately the propositional content of > Wikipedia articles. Well, perhaps Cyc falls short on both fronts: it is too broad to be CD: it represents much more meaning than can be built from CD's-like atoms. But the representation is provided ad-hoc by knowledge ingeneers, it is not "grounded in the general net of meaning", which in Multinet is provided by the NL semantics. But perhaps these are just false slogans and Cyc knowledge is dense enough. > (5) Sorts and Features - To me these are Cyc-like, except that Cyc made the > decision to represent appropriate features as class membership (e.g. the > property cyc:mainColorOfObject is a sub-property of cyc:isa / rdf:type). > Supposedly, this representation is faster for Cyc deductive inference. On the "red petal" slide you see that Multinet is flexible about how things are represented (e.g. general rules transform between PROP and ATTR-VAL, similarily rules relate features and their corresponding concept nodes; well I don't know enough about features in Multinet). > (6) Knowledge types - Multinet appears more expressive in this respect than > the Cyc ontology, although the Cyc KR language CycL allows meta assertions > so I believe that MultiNet could be encoded in a Cyc KB. I believe Cyc is well worked-out by the many man-years of development. (I still need to "get my hands dirty".) > (7) Conceptual capsule - interesting, Cyc has the supporting assertions but > not the notion of what assertions uniquely define an object. This seems important to the object/concept-centeredness and "intensionality" of Multinet. > (8) How does Multinet address connectionism or probabilistic inference (e.g. > Bayes)? Did I miss where a probability may be associated with an assertion, > or with an argument place in an assertion? The book only mentions that the underlying logic should have "levels of truthworthiness". Multinet doesn't represent probabilities because neither does language: Multinet has modal modifiers, e.g. "(very) probable", "(very) unlikely" etc. and intensional generalized quantifiers, like "some", "most". > (8) lexicon - need more examples for me to comment. I would be interested > in your comments on my adoption of Fluid Construction Grammar as a solution > to the NL to semantics mapping problem. > I'll try to find time for some more in-depth comments here. ------------------------------------------- agi Archives: http://www.listbox.com/member/archive/303/=now RSS Feed: http://www.listbox.com/member/archive/rss/303/ Modify Your Subscription: http://www.listbox.com/member/?member_id=8660244&id_secret=98558129-0bdb63 Powered by Listbox: http://www.listbox.com
