On Monday 15 October 2007 01:25:22 pm, Edward W. Porter wrote: > I'm arguing that its meaning makes an assumption about the nature of > semantics that obscures rather than informing some important questions > > WHAT EXACTLY DO YOU MEAN?
I think that will become clearer below: > I JUST READ THE ABSTRACT OF Harnad, S. (1990) The Symbol Grounding > Problem. Physica D 42: 335-346. ON THE WEB, AND IT SEEMS HE IS TALKING > ABOUT USING SOMETHING LIKE A GEN/COMP HIERARCHY OF REPRESENTATION HAVING > AS A BOTTOM LAYER SIMPLE SENSORY PATTERNS, AS A BASIS OF GROUNDING. Basically. He proposes his notion of grounding as an escape from the problem, as he describes it, of learning Chinese from a Chinese-Chinese dictionary. You chase definitions around and around, but never get to where the symbols have any meaning to you. > SO HOW DOES THE CALCULATOR HAVE SIGNIFICANTLY MORE OF THIS TYPE OF > GROUNDING THAN 10 IN BINARY. What i said was that the calculator does NOT nave this kind of grounding: “I'd just say that for the 2 in my calculator, the answer is no, in Harnad's fairly precise sense of grounding." What it does have is an internal system whose objects and workings reflect the ontology and etiology of arithmetic as we see it in the outside world. If I type 2+3 into the calculator, it displays 5. If I hold 2 sandwiches in my left hand, and 3 in my right, and put them all on a plate, when I count the sandwiches on the plate, lo and behold, there are 5 sandwiches. So, I claim, the symbols in the calculator have meaning because they are part of a model that reflects some phenomenon of interest, and can be used to predict it. They have NO grounding in Harnad's sense -- the calculator has no sensory patterns that reflect quanitites as we perceive them. > Typically one assumes that experience means the experience of the person, > AI, > or whatever that we're talking about... > > IF THAT IS TRUE, MUCH OF MY UNDERSTANDING OF SCIENCE AND AI IS NOT > GROUNDED, SINCE IT HAS BEEN LEARNED LARGELY BY READING, HEARING LECTURES, > AND WATCHING DOCUMENTARIES. Yes indeed -- but that doesn't mean (necessarily) that what you know is wrong, as long as the models you have reflect the realities they should. And this is why I say grounding in Harnad's sense is a red herring. > I claim that we can talk about a more proximate > criterion for semantics, which is that the system forms a model of some > phenomenon of interest. It may well be that experience, narrowly or > broadly > construed, is often the best way of producing such a system (and in fact I > believe that it is), but the questions are logically separable. > > THIS MAKES SENSE, BUT THIS WOULD COVER A LOT OF SYSTEM THAT ARE NOT > GROUNDED IN THE WAY MOST OF USE US THAT WORD Again an argument to use a different word. I know a lot of science for which I haven't personally done the experiments that I believe are the justifications for my knowledge. I'd claim that my concept of inertia is grounded in personal experience but that my concept of magnetic induction is more or less synthesized of other abstract mathematical concepts. But it happens to work well enough that I can build working transformers. So I believe it's "true" in the sense that it is a valid model of the phenomenon. > It's conceivable to have a system that has the appropriate semantics that > was just > randomly produced... > > I ASSUME THAT BY RANDOMLY PRODUCED, YOU DONT MEAN THAT THE SYSTEM WOULD > BE TOTALLY RANDOM, IN WHICH CASE IT WOULD SEEM THE CONCEPT OF A MODEL > WOULD BE MEANINGLESS. Nope. If the model was formed at random, BUT HAPPENS TO MATCH REALITY anyway, it has as much meaning as one built up by painstaking experimentation. But of course the probability of this happening is vanishingly small if the model is complex. > I WOULD PICK AS A GOOD EXAMPLE OF A SEMANTIC SYSTEM THAT IS SOMEWHAT > INDEPENDENT OF PHYSICAL REALITY, BUT YET HAS PROVED USEFUL, AT LEAST FOR > ENTERTAINMENT, IS THE HARRY POTTER SERIES, OR SOME OTHER FICTIONAL WORLD > WHICH CREATES A FICTIONAL REALITY IN WHICH THERE IS A CERTAIN REGULARITY > TO THE BEHAVIOR AND CHARACTERISTICS OF THE FICTITIOUS PEOPLE AND PLACES IT > DESCRIBES. There's a physical reality that the world of magic reflects, oddly enough, that's very close to home. The two key magical laws, i.e. of similarity and contagion, are remarkably good descriptions of the heuristics by which our minds form associations... Cheers! Josh ----- This list is sponsored by AGIRI: http://www.agiri.org/email To unsubscribe or change your options, please go to: http://v2.listbox.com/member/?member_id=8660244&id_secret=53804699-7f7e7e
