In this & surrounding discussions, everyone seems deeply confused - & it's nothing personal, so is our entire culture - about the difference between
SYMBOLS 1. "Derek Zahn" "curly hair" "big jaw" "intelligent eyes" ..... etc. etc and IMAGES 2. http://robot-club.com/teamtoad/nerc/h2-derek-sunflower.JPG I suggest that everytime you want to think about this area, you all put symbols besides the corresponding images, and slowly it will start to become clear that each does things the other CAN'T do, period. We are all next to illiterate - and I mean, mind-blowingly ignorant - about how images function. What, for example, does an image of D.Z. or any person, do, that no amount of symbols - whether words, numbers, algebraic formulae, or logical propositions - could ever do? Why are images almost always more powerful than the corresponding symbols? Why do they communicate so much faster? Derek: Related obliquely to the discussion about pattern discovery algorithms.... What is a symbol? I am not sure that I am using the words in this post in exactly the same way they are normally used by cognitive scientists; to the extent that causes confusion, I'm sorry. I'd rather use words in their strict conventional sense but I do not fully understand what that is. These thoughts are fuzzier than I'd like; if I was better at de-fuzzifying them I might be a pro instead of an amateur! Proposition: a "symbol" is a token with both denotative and model-theoretic semantics. The denotative semantacs are what makes a symbol refer to something or "be about" something. The model-theoretic semantics allow symbol processing operations to occur (such as reasoning). I believe this is a somewhat more restrictive use of the word "symbol" than is necessarily implied by Newell and Simon in the Physical Symbol System Hypothesis, but my aim is engineering rather than philosophy. I'm actually somewhat skeptical that human beings use symbols in this sense for much of our cognition. We appear to be a million times better at it than any other animal, and that is the special thing that makes us so great, but we still aren't very good at it. However, most of the things we want to build AGI *for* require us to greatly expand the symbol processing capabilities of mere humans. I think we're mostly interested in building artificial scientists and engineers rather than artificial musicians. Since computer programs, engineering drawings, and physics theories are explicitly symbolic constructs, we're more interested in effectively creating symbols than in the totality of the murky "subsymbolic" world supporting it. To what extent can we separate them? I wish I knew. In this view, "subsymbolic" simply refers to tokens that lack some of the features of symbols. For example, a representation of a pixel from a camera has clear denotational semantics but it is not elaborated as well as a better symbol would be ("the light coming from direction A at time B" is not as useful as "the light reflecting off of Fred's pinky fingernail"). Similarly, and more importantly, subsymbolic products of sensory systems lack useful model-theoretic semantics. The "origin of symbols" problem involves how those semantics arise -- and to me it's the most interesting piece of the AGI puzzle. Is anybody else interested in this kind of question, or am I simply inventing issues that are not meaningful and useful? ------------------------------------------------------------------------------ agi | Archives | Modify Your Subscription ------------------------------------------------------------------------------ No virus found in this incoming message. Checked by AVG. Version: 7.5.519 / Virus Database: 269.22.1/1349 - Release Date: 3/29/2008 5:02 PM ------------------------------------------- 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