Saturday, November 29, 2008
Naming Similar Impressions of the World
 I may refer to a man's hand using the phrase "John Black's hand", or the like, and associate with that phrase a transduction of John Black's hand, similar to the transduction formed by a transducer toy, like the one shown below. You may have a nearly identical transduction of that hand, if you have a transducer toy just like ours and you press it against my hand. And you may come to associate the same name with your transduction of that hand as I do with my transduction of it. So there is no need for an agreement between us. But there is a need for our respective transductions to be associated with the same name. |
 Any particular transduction formed by a transducer toy is as much about the world as it is about the toy. That is one of the reasons for its special appeal. Similarly, the world molds the physics of our memory just as surely as this toy was shaped by my hand. It would be senseless to conceive of a transduction as something separate or independent of the hand that formed it. So too, the idea of mental representations or concepts of the world being separate and independent of the world is senseless. We share names associated with our mutual imprints of the world. And those names refer because the world is one and our sensory apparatus is nearly identical and something has brought us all to associate a common name with our separate transductions. |
 What must happen for the phrase "John Black's hand" to refer is a common association of that name with our mutual, independent imprinting of John Black's hand using the same kind of transducer. Common transductions, not contracts, form the basis of this kind of concrete reference. |
Labels: language, reference, semantics, transduction
Sunday, November 23, 2008
The Semantic Web and the Singular Expression of Fact
On the web, a document needs to be posted once, because it is accessible from everywhere at about the same cost. This is a great advantage over physical publishing since reaching everyone with a publication requires sufficient duplicates and distribution for everyone to have access. Will the Semantic Web provide the the same advantage for factual data?
How many times does the fact that snow is white need to be expressed? For that matter, how many times is snow white? Is there one such fact or is the fact itself repeated over and over again with every snowflake? Let's suppose that there is only one such fact, no matter how many times it is expressed. Then are the many expressions of that one fact superfluous? Could we get away with just one expression of it, provided everyone could link to it with equal low cost?
How many times does the fact that snow is white need to be expressed? For that matter, how many times is snow white? Is there one such fact or is the fact itself repeated over and over again with every snowflake? Let's suppose that there is only one such fact, no matter how many times it is expressed. Then are the many expressions of that one fact superfluous? Could we get away with just one expression of it, provided everyone could link to it with equal low cost?Labels: distributed knowledge, semantics, truth
Sunday, April 22, 2007
The Semantic Web: Global Agreements? Or Symbolic Theft and the Ubiquitous Copying of URI
There is still controversy, but most agree that big globally accepted ontologies are not likely in the near future, if ever. Critics of the Semantic Web (upper case) say such ontologies are required and that this will be the downfall of the technology, since the required global agreements will never happen in the real, factious world. Semantic Web proponents come back and say this criticism is due to a misunderstanding of the way the technology is designed to work. They claim the semantic web (lower case) is designed for the organic growth of a beautiful fractal tangle of interlocking local ontologies. But proponents usually finish with a mumbled bit about agreement, 'there must be some", if just to avoid a cacophony of chaotic islands of solipsisms. So what gives? What sort of agreement, if any, is going to be necessary, accepting that it will not be the one big, global, uber-ontology?
In Symbol Grounding and the Symbolic Theft Hypothesis the authors, Angelo Cangelosi, Alberto Greco and Stevan Harnad, write, "There are two opposite ways of acquiring categories. First, we can use “sensorimotor toil”, in which new categories are acquired through real-time, feedback-corrected, trial and error experience. Secondly, we can use “symbolic theft”, in which new categories are acquired through language, based on hearsay from propositions (e.g., through boolean combinations of symbols describing them). In competition, symbolic theft always outperforms sensorimotor toil. It is more efficient than toil because only one propositional description of a new category is enough to learn it. In contrast, repeated experience is required to learn a category by sensorimotor toil. Due to this significant advantage, it has been hypothesized that symbolic theft is the basis of the adaptive advantage of language (Harnad, 1996). However, some basic categories must still be learned by toil to avoid an infinite regress in the symbol grounding problem."
I believe such symbolic theft (which is a victimless 'crime') is a critical part of the semantic web. The reason is that most of the semantics in the semantic web comes from natural languages like English. Most URIs have recognizable English words embedded in them and that gives them the same shared semantics as the English words themselves. In other words, most URI ride on the back of the common knowledge of natural language words for their meaning. There is no need to come to agreement about such a URI, not because common knowledge is not necessary, but because it already exists about the embedded natural language words that compose the URI. In short, there is no need for a globally agreed upon ontology because the semantic web is grounded in natural language, which is already a widely accepted, if not a globally agreed upon, uber-something, with ontological elements. So I propose ubiquitous copying, or symbolic theft, of word meaning is the actual route to common knowledge, rather than global agreement.
But there is another way that symbolic theft can serve the semantic web. That is through the copying and reuse of URI. The more a URI is copied and reused, the more common knowledge of it accumulates in the communities that use it. If this is true, then the semantic web depends on programmers, database designers, and authors getting into the habit of selecting their URIs for things from a common naming source - the web. And they will do such stealing when it becomes easier and cheaper to copy than it is to invent new terms. When all the creators of data copy the same name for an element up front, there will be no need to translate, merge, integrate, or otherwise massage data to work together. Like in natural languages, these copied terms will form the very essence of communication. As the semantic web really takes off, programmers should and will be able to steal variable and data element names, relational database table and column names, xml schema element names, object attribute names, and more from the web. This will be something available in Eclipse and in other editors where developers actually need to create the names of data elements.
But what about the Symbol Grounding Problem? It is real. It is what makes computers spit out errors so preposterous that even most three year olds could never make them. In persons, it is what causes superstitions, prejudice, and the madness of crowds. In societies, it leads to nationalism, ethnic cleansing, and genocide. Ungrounded symbols run amok, in humans as well as machines. For humans, the main antidote is science and the rational investigation of experience, i.e., sensorimotor toil. Is there a solution to the symbol grounding problem for computing machinery that can be used in the semantic web? That is one of the continuing topics of this blog.
In Symbol Grounding and the Symbolic Theft Hypothesis the authors, Angelo Cangelosi, Alberto Greco and Stevan Harnad, write, "There are two opposite ways of acquiring categories. First, we can use “sensorimotor toil”, in which new categories are acquired through real-time, feedback-corrected, trial and error experience. Secondly, we can use “symbolic theft”, in which new categories are acquired through language, based on hearsay from propositions (e.g., through boolean combinations of symbols describing them). In competition, symbolic theft always outperforms sensorimotor toil. It is more efficient than toil because only one propositional description of a new category is enough to learn it. In contrast, repeated experience is required to learn a category by sensorimotor toil. Due to this significant advantage, it has been hypothesized that symbolic theft is the basis of the adaptive advantage of language (Harnad, 1996). However, some basic categories must still be learned by toil to avoid an infinite regress in the symbol grounding problem."
I believe such symbolic theft (which is a victimless 'crime') is a critical part of the semantic web. The reason is that most of the semantics in the semantic web comes from natural languages like English. Most URIs have recognizable English words embedded in them and that gives them the same shared semantics as the English words themselves. In other words, most URI ride on the back of the common knowledge of natural language words for their meaning. There is no need to come to agreement about such a URI, not because common knowledge is not necessary, but because it already exists about the embedded natural language words that compose the URI. In short, there is no need for a globally agreed upon ontology because the semantic web is grounded in natural language, which is already a widely accepted, if not a globally agreed upon, uber-something, with ontological elements. So I propose ubiquitous copying, or symbolic theft, of word meaning is the actual route to common knowledge, rather than global agreement.
But there is another way that symbolic theft can serve the semantic web. That is through the copying and reuse of URI. The more a URI is copied and reused, the more common knowledge of it accumulates in the communities that use it. If this is true, then the semantic web depends on programmers, database designers, and authors getting into the habit of selecting their URIs for things from a common naming source - the web. And they will do such stealing when it becomes easier and cheaper to copy than it is to invent new terms. When all the creators of data copy the same name for an element up front, there will be no need to translate, merge, integrate, or otherwise massage data to work together. Like in natural languages, these copied terms will form the very essence of communication. As the semantic web really takes off, programmers should and will be able to steal variable and data element names, relational database table and column names, xml schema element names, object attribute names, and more from the web. This will be something available in Eclipse and in other editors where developers actually need to create the names of data elements.
But what about the Symbol Grounding Problem? It is real. It is what makes computers spit out errors so preposterous that even most three year olds could never make them. In persons, it is what causes superstitions, prejudice, and the madness of crowds. In societies, it leads to nationalism, ethnic cleansing, and genocide. Ungrounded symbols run amok, in humans as well as machines. For humans, the main antidote is science and the rational investigation of experience, i.e., sensorimotor toil. Is there a solution to the symbol grounding problem for computing machinery that can be used in the semantic web? That is one of the continuing topics of this blog.
Labels: common knowledge, evolution, language, semantics
Saturday, April 14, 2007
John Searle's Hypothesis of the Background
In his book, The Rediscovery of the Mind, John Searle, writes about his hypothesis of the Background, which asserts that all language semantics depends on a shared context,
"It is tempting to think that this argument rests on ambiguity, marginal cases, etc. But that is a mistake. Once full explicitness has been achieved, once all structural and lexical ambiguities have been removed, the problem of the Background still arises. You can see this if you see that progressive efforts at precision are not sufficient to remove the need for the Background. Suppose I go into the restaurant and order a meal. Suppose I say, speaking literally, "Bring me a steak with fried potatoes." Even though the utterance is meant and understood literally, the number of possible misinterpretations is strictly limitless. I take it for granted that they will not deliver the meal to my house, or to my place of work. I take it for granted that the steak will not be encased in concrete, or petrified. It will not be stuffed into my pockets or spread over my head. But none of these assumptions was made explicit in the literal utterance. The temptation is to think that I could make them fully explicit by simply adding them as further restrictions, making my original order more precise. But that is also a mistake. First, it is a mistake because there is no limit to the number of additions I would have to make to block possible misinterpretations, and second, each of the additions is itself subject to different interpretations."
"It is tempting to think that this argument rests on ambiguity, marginal cases, etc. But that is a mistake. Once full explicitness has been achieved, once all structural and lexical ambiguities have been removed, the problem of the Background still arises. You can see this if you see that progressive efforts at precision are not sufficient to remove the need for the Background. Suppose I go into the restaurant and order a meal. Suppose I say, speaking literally, "Bring me a steak with fried potatoes." Even though the utterance is meant and understood literally, the number of possible misinterpretations is strictly limitless. I take it for granted that they will not deliver the meal to my house, or to my place of work. I take it for granted that the steak will not be encased in concrete, or petrified. It will not be stuffed into my pockets or spread over my head. But none of these assumptions was made explicit in the literal utterance. The temptation is to think that I could make them fully explicit by simply adding them as further restrictions, making my original order more precise. But that is also a mistake. First, it is a mistake because there is no limit to the number of additions I would have to make to block possible misinterpretations, and second, each of the additions is itself subject to different interpretations."
Labels: ambiguity, context, semantics
