Path: utzoo!utgpu!news-server.csri.toronto.edu!cs.utexas.edu!sun-barr!lll-winken!elroy.jpl.nasa.gov!usc!isi.edu!smoliar From: smoliar@isi.edu (Stephen Smoliar) Newsgroups: comp.ai.philosophy Subject: Re: Just Minds and Machines this time Message-ID: <16537@venera.isi.edu> Date: 28 Jan 91 22:10:19 GMT References: <11656.9101241836@s4.sys.uea.ac.uk> <1991Jan25.022026.12999@watdragon.waterloo.edu> <16510@venera.isi.edu> <1991Jan27.185935.18038@watdragon.waterloo.edu> Reply-To: smoliar@venera.isi.edu (Stephen Smoliar) Organization: Information Sciences Institute, Univ. of So. California Lines: 97 In article <1991Jan27.185935.18038@watdragon.waterloo.edu> cpshelley@violet.uwaterloo.ca (cameron shelley) writes: >In article <16510@venera.isi.edu> smoliar@venera.isi.edu (Stephen Smoliar) writes: > >>Let us suppose that we still have some sort of multidimensional space as a >>metaphor for reality; but rather than filling it with an energy landscape, >>suppose we instead insert a linkage structure, sort of like a linear >>undirected >>graph, as a model of an agent's "knowledge" (whatever that may mean). The >>reason I wish to appeal to this metaphor is as an alternative to modeling >>reasoning in terms of the trajectory of a point in the space which seeks out >>an energy sink. Think, instead, of accommodating a point in space by asking >>how that linkage structure might get flexed, or, perhaps expanded, in such a >>way that it ultimately "meets" that point; that resulting "meeting" might >>then >>be regarded as an "interpretation" of that point. Given sufficiently liberal >>laws of what you could do with the linkages, any given point would obviously >>be subject to multiple interpretations, which would mean it is not really a >>fixed "point in reality" (which, as I assumed above, was one of the problems >>Wittgenstein was trying to get away from). From Cam's point of view, the >>question of whether or not the point is "well-formed" ultimately boils down >>to whether or not the linkages can be configured to "meet" it. >> >Hmmm. An interesting notion! Could you elabourate on "meet"? If I >understand correctly, you mean the structure can be deformed by some >composition of adjustments applied to its parts. This seems plausible >with the proviso that the entire structure need not be completely >connected (or am I missing something?). The notion "ill-formed" would >be the requirement of an 'illegal' translation of the structure, while >"ill-transmitted" would be uncertainty about the point being met. >Would we have to know all possible translations of the structure in >order to separate 'legal' from 'illegal'? Complexity could then be >measured by the number of elementary translations and deformations >necessary to meet the point in question. By then, the default (or >acquisition of) the structure becomes an issue... > I think we're basically on the same channel here. I was using "meet" in the set-theoretic sense of intersection. The more I think about it, I think there are (at least) two implications to this approach: 1. There is the issue of whether or not, and how, the linkages can be manipulated in order to achieve a meeting. 2. There is the issue of WHERE on the linkages this meeting actually takes place. In a very loose sense the first issue has to do with whether or not that particular point in space is well-formed, in the notion that Cam wishes to pursue. Under the assumption that it IS well-formed, the second issue then takes on the matter of HOW it will be interpreted. This is what I was trying to get at in saying that different ways of manipulating the linkages might lead to different interpretations: Depending on the specific manipulations, the point may meet different locations on the linkage, itself. Does the structure have to be connected? I do not see that as necessary. I am more interested in the extent to which this metaphor can be useful interpreted into a set of viable rules for manipulation the structure. There is no reason to eliminate rules which would pull the structure apart unless it could be demonstrated that they led to undesirable consequences (such as, perhaps, an inability to recover information about where the meeting took place when it was finally achieved). My own sense of aesthetics seems more inclined to allowing the "limbs" of the structure to be stretched or shrunken, rather than allowing the structure to be pulled apart; but, as I said, I think it is more important to start thinking about reasonable ways to talk about the manipulation, itself. Another possibility might be that the manipulations are sufficiently powerful that the structure can always access any point in the space. In this case there would no longer be an issue of ill-formed points. This might be a way in which the manipulation of the structure reflects an adjustment in interpretation to accommodate what might have otherwise been regarded as an ill-formed point. Perhaps I can try to illustrate what I am trying to say here with a concrete example. Peter Todd recently published some of his work in trying to use connectionism for musical composition. The basic approach was to "train" a network with some examples of melodies and then, through control of some inputs, allow a trained network to synthesize new melodies. During training, Todd has some very strict rules about what constitutes well-formed input. However, when he leaves the network to its own devices, so to speak, the results it yields do not respect those rules. As an outside observer, he interprets them in a way which basically "makes sense" according to the original INTENT of his rules. To return to my metaphor, in the strictest sense Todd's network converges to points in space which are actually ill-formed. However, his human intelligence controls this metaphorical system of linkages in such a way that he can still assign interpretations to those points which are consistent with what he originally had in mind. Robustness is thus a matter of finding the best interpretation for a given situation (for some metric for "best") rather than trying to decide, in any absolute sense, whether or not that situation is "well-formed." -- USPS: Stephen Smoliar 5000 Centinela Avenue #129 Los Angeles, California 90066 Internet: smoliar@venera.isi.edu