Stephen, Yes, I think your spreading-activation approach makes sense and has plenty of potential.
Our approach in OpenCog is actually pretty similar, given that our importance-updating dynamics can be viewed as a nonstandard sort of spreading activation... I think this kind of approach can work, but I also think that getting it to work generally and robustly -- not just in toy examples like the one I gave -- is going to require a lot of experimentation and trickery. Of course, if the AI system has embodied experience, this provides extra links for the spreading activation (or analogues) to flow along, thus increasing the odds of meaningful results... Also, I think that spreading-activation type methods can only handle some cases, and that for other cases one needs to use explicit inference to do the disambiguation. My point for YKY was (as you know) not that this is an impossible problem but that it's a fairly deep AI problem which is not provided out-of-the-box in any existing NLP toolkit. Solving disambiguation thoroughly is AGI-hard ... solving it usefully is not ... but solving it usefully for *prepositions* is cutting-edge research going beyond what existing NLP frameworks do... -- Ben G On Mon, Sep 29, 2008 at 1:25 PM, Stephen Reed <[EMAIL PROTECTED]> wrote: > Ben gave the following examples that demonstrate the ambiguity of the > preposition "with": > > People eat food with forks > > People eat food with friend[s] > > People eat food with ketchup > > The Texai bootstrap English dialog system, whose grammar rule engine I'm > currently rewriting, uses elaboration and spreading activation to perform > disambiguation and pruning of alternative interpretations. Let's step > through how Texai would process Ben's examples. According to > Wiktionary<http://en.wiktionary.org/wiki/with>, > "with" has among its word senses the following: > > - as an instrument; by means of > > > - in the company of; alongside; along side of; close to; near to > > > - in addition to, as an accessory to > > Its clear when I make these substitutions which word sense is to be > selected: > > People eat food by means of forks > > People eat food in the company of friends > > People eat ketchup as an accessory to food > > Elaboration of the Texai discourse context provides additional entailed > propositions with respect to the objects actually referenced in the > utterance. The elaboration process is efficiently performed by spreading > activation <http://en.wikipedia.org/wiki/Spreading_activation> over the KB > from the focal terms with respect to context. The links explored by this > process can be formed by offline deductive inference, or learned from > heuristic search and reinforcement learning, or simply taught by a mentor. > > Relevant elaborations I would expect Texai to make for the example > utterances are: > > a fork is an instrument > > there are activities that a person performs as a member of a group of > friends; to eat is such an activity > > ketchup is a condiment; a condiment is an accessory with regard to food > > Texai considers all interpretations simultaneously, in a transient > spreading activation network whose nodes are the semantic propositions > contained within the elaborated discourse context and whose links are formed > when propositions share an argument concept. Negative links are formed > between propositions from alternative interpretations. At > AGI-09<http://www.agi-09.org/>I hope to demonstrate this technique in which > the correct word sense of > "with" can be determined from the highest activated nodes in the elaborated > discourse context after spreading activation has quiesced. > > -Steve > > Stephen L. Reed > Artificial Intelligence Researcher > http://texai.org/blog > http://texai.org > 3008 Oak Crest Ave. > Austin, Texas, USA 78704 > 512.791.7860 > > ----- Original Message ---- > From: Ben Goertzel <[EMAIL PROTECTED]> > To: agi@v2.listbox.com > Sent: Monday, September 29, 2008 8:18:30 AM > Subject: Re: [agi] universal logical form for natural language > > > > On Mon, Sep 29, 2008 at 4:23 AM, YKY (Yan King Yin) < > [EMAIL PROTECTED]> wrote: > >> On Mon, Sep 29, 2008 at 4:10 AM, Abram Demski <[EMAIL PROTECTED]> >> wrote: >> > >> > How much will you focus on natural language? It sounds like you want >> > that to be fairly minimal at first. My opinion is that chatbot-type >> > programs are not such a bad place to start-- if only because it is >> > good publicity. >> >> I plan to make use of Steven Reed's Texai -- he's writing a dialog >> system that can translate NL to logical form. If it turns out to be >> unfeasible, I can borrow a simple NL interface from somewhere else. >> > > > Whether using an NL interface like Stephen's is feasible or not, really > depends on your expectations for it. > > Parsing English sentences into sets of formal-logic relationships is not > extremely hard given current technology. > > But the only feasible way to do it, without making AGI breakthroughs > first, is to accept that these formal-logic relationships will then embody > significant ambiguity. > > Pasting some text from a PPT I've given... > > *** > Syntax parsing, using the NM/OpenCog narrow-AI RelEx system, transforms > > Guard my treasure with your life > > into > > _poss(life,your) > _poss(treasure,my) > _obj(Guard,treasure) > with(Guard,life) > _imperative(Guard) > > Semantic normalization, using the RelEx rule engine and the FrameNet > database, transforms this into > > Protection:Protection(Guard, you) > Protection:Asset(Guard, treasure) > Possession:Owner(treasure, me) > Protection:Means(Guard, life) > Possession:Owner(life,you) > _imperative(Guard) > > But, we also get > > Guard my treasure with your sword. > > Protection:Protection(Guard, you) > Protection:Asset(Guard, treasure) > Possession:Owner(treasure, me) > Protection:Means(Guard, sword) > Possession:Owner(sword,you) > _imperative(Guard) > > Guard my treasure with your uncle. > > Protection:Protection(Guard, you) > Protection:Protection(Guard, uncle) Protection:Asset(Guard, treasure) > Possession:Owner(treasure, me) > Protection:Means(Guard, sword) > Possession:Owner(uncle,you) > > ***** > > The different senses of the word "with" are not currently captured by the > RelEx NLP > system, and that's a hard problem for current computational linguistics > technology > to grapple with. > > I think it can be handled via embodiment, i.e. via having an AI system > observe > the usage of various senses of "with" in various embodied contexts. > > Potentially it could also be handled via statistical-linguistics methods > (where the > contexts are then various documents the senses of "with" have occurred in, > rather > than embodied situations), though I'm more skeptical of this method. > > In a knowledge entry context, this means that current best-of-breed NL > interpretation systems will parse > > People eat food with forks > > People eat food with friend > > People eat food with ketchup > > into similarly-structured logical relationships. > > This is just fine, but what it tells you is that **reformulating English > into logical > formalism does not, in itself, solve the disambiguation problem**. > > The disambiguation problem remains, just on the level of disambiguating > formal-logic structures into less ambiguous ones. > > Using a formal language like CycL to enter knowledge is one way of largely > circumventing this problem ... using Lojban would be another ... > > (Again I stress that having humans encode knowledge is NOT my favored > approach to AGI, but I'm just commenting on some of the issues involved > anyway...) > > -- Ben G > > > ------------------------------ > *agi* | Archives <https://www.listbox.com/member/archive/303/=now> > <https://www.listbox.com/member/archive/rss/303/> | > Modify<https://www.listbox.com/member/?&;>Your Subscription > <http://www.listbox.com> > > ------------------------------ > *agi* | Archives <https://www.listbox.com/member/archive/303/=now> > <https://www.listbox.com/member/archive/rss/303/> | > Modify<https://www.listbox.com/member/?&;>Your Subscription > <http://www.listbox.com> > -- Ben Goertzel, PhD CEO, Novamente LLC and Biomind LLC Director of Research, SIAI [EMAIL PROTECTED] "Nothing will ever be attempted if all possible objections must be first overcome " - Dr Samuel Johnson ------------------------------------------- agi Archives: https://www.listbox.com/member/archive/303/=now RSS Feed: https://www.listbox.com/member/archive/rss/303/ Modify Your Subscription: https://www.listbox.com/member/?member_id=8660244&id_secret=114414975-3c8e69 Powered by Listbox: http://www.listbox.com
