Artificial Intelligence =97 Sanskrit =97 The Age = of=20 Information =97=20 NASA =97 Knowledge Representation

Vedic Science

3D"Sanskrit

Sanskrit & Artificial Intelligence = =97 NASA
Knowledge=20 Representation in Sanskrit and Artificial Intelligence

by
Rick Briggs
Roacs, NASA Ames = Research=20 Center, Moffet Field, California

Abstract

3D"NASA In the = past twenty=20 years, much time, effort, and money has been expended on designing an=20 unambiguous representation of natural languages to make them accessible = to=20 computer processing. These efforts have centered around creating = schemata=20 designed to parallel logical relations with relations expressed by the = syntax=20 and semantics of natural languages, which are clearly cumbersome and = ambiguous=20 in their function as vehicles for the transmission of logical data.=20 Understandably, there is a widespread belief that natural languages are=20 unsuitable for the transmission of many ideas that artificial languages = can=20 render with great precision and mathematical rigor.

But=20 this dichotomy, which has served as a premise underlying much work in = the areas=20 of linguistics and artificial intelligence, is a false one. There is at = least=20 one language, Sanskrit, which for the duration of almost 1,000 years was = a=20 living spoken language with a considerable literature of its own. = Besides works=20 of literary value, there was a long philosophical and grammatical = tradition that=20 has continued to exist with undiminished vigor until the present = century. Among=20 the accomplishments of the grammarians can be reckoned a method for = paraphrasing=20 Sanskrit in a manner that is identical not only in essence but in form = with=20 current work in Artificial Intelligence. This article demonstrates that = a=20 natural language can serve as an artificial language also, and that much = work in=20 AI has been reinventing a wheel millenia old.

3D"Sanskrit

First, a typical Knowledge Representation = Scheme=20 (using Semantic Nets) will be laid out, followed by an outline of the = method=20 used by the ancient Indian Grammarians to analyze sentences = unambiguously.=20 Finally, the clear parallelism between the two will be demonstrated, and = the=20 theoretical implications of this equivalence will be = given.

Semantic = Nets
For the sake of = comparison, a=20 brief overview of semantic nets will be given, and examples will be = included=20 that will be compared to the Indian approach. After early attempts at = machine=20 translation (which were based to a large extent on simple dictionary = look-up)=20 failed in their effort to teach a computer to understand natural = language, work=20 in AI turned to Knowledge Representation.

Since translation is not simply a map = from lexical=20 item to lexical item, and since ambiguity is inherent in a large number = of=20 utterances, some means is required to encode what the actual meaning of = a=20 sentence is. Clearly, there must be a representation of meaning = independent of=20 words used. Another problem is the interference of syntax. In some = sentences=20 (for example active/passive) syntax is, for all intents and purposes,=20 independent of meaning. Here one would like to eliminate considerations = of=20 syntax. In other sentences the syntax contributes to the meaning and = here one=20 wishes to extract it.

3D"Sanskrit

I will consider a "prototypical" semantic = net=20 system similar to that of Lindsay, Norman, and Rumelhart in the hopes = that it is=20 fairly representative of basic semantic net theory. Taking a simple = example=20 first, one would represent "John gave the ball to Mary" as in Figure 1. = Here=20 five nodes connected by four labeled arcs capture the entire meaning of = the=20 sentence. This information can be stored as a series of=20 "triples":

give, agent, John

give, object, ball

give, recipient, Mary

give, time, past.

Note that grammatical information has = been=20 transformed into an arc and a node (past tense). A more complicated = example will=20 illustrate embedded sentences and changes of state:

John Mary

book past

Figure 1.

"John told Mary that the train moved out = of the=20 station at 3 o'clock."

As shown in Figure 2, there was a change = in state=20 in which the train moved to some unspecified location from the station. = It went=20 to the former at 3:00 and from the latter at 3:O0. Now one can routinely = convert=20 the net to triples as before.

The verb is given central significance in = this=20 scheme and is considered the focus and distinguishing aspect of the = sentence.=20 However, there are other sentence types which differ fundamentally from = the=20 above examples. Figure 3 illustrates a sentence that is one of "state" = rather=20 than of "event ." Other nets could represent statements of time, = location or=20 more complicated structures.

A verb, say, "give," has been taken as = primitive,=20 but what is the meaning of "give" itself? Is it only definable in terms = of the=20 structure it generates? Clearly two verbs can generate the same = structure. One=20 can take a set-theoretic approach and a particular give as an element of = "giving=20 events" itself a subset of ALL-EVENTS. An example of this approach is = given in=20 Figure 4 ("John, a programmer living at Maple St., gives a book to Mary, = who is=20 a lawyer"). If one were to "read" this semantic net, one would have a = very long=20 text of awkward English: "There is a John" who is an element of the = "Persons"=20 set and who is the person who lives at ADRI, where ADRI is a subset of=20 ADDRESS-EVENTS, itself a subset of 'ALL EVENTS', and has location '37 = Maple=20 St.', an element of Addresses; and who is a "worker" of 'occupation 1'. = .=20 .etc."

The degree to which a semantic net (or = any=20 unambiguous, nonsyntactic representation) is cumbersome and odd-sounding = in a=20 natural language is the degree to which that language is "natural" and = deviates=20 from the precise or "artificial." As we shall see, there was a language = spoken=20 among an ancient scientific community that has a deviation of=20 zero.

The hierarchical structure of the above net and = the=20 explicit descriptions of set-relations are essential to really capture = the=20 meaning of the sentence and to facilitate inference. It is believed by = most in=20 the AI and general linguistic community that natural languages do not = make such=20 seemingly trivial hierarchies explicit. Below is a description of a = natural=20 language, Shastric Sanskrit, where for the past millenia successful = attempts=20 have been made to encode such information.

Shastric = Sanskrit

The sentence:

(1) "Caitra goes to the village." = (graamam gacchati=20 caitra)

receives in the analysis given by an=20 eighteenth-century Sanskrit Grammarian from Maharashtra, India, the = following=20 paraphrase:

(2) "There is an activity which leads to = a=20 connection-activity which has as Agent no one other than Caitra, = specified by=20 singularity, [which] is taking place in the present and which has as = Object=20 something not different from 'village'."

The author, Nagesha, is one of a group of = three or=20 four prominent theoreticians who stand at the end of a long tradition of = investigation. Its beginnings date to the middle of the first millennium = B.C.=20 when the morphology and phonological structure of the language, as well = as the=20 framework for its syntactic description were codified by Panini. His = successors=20 elucidated the brief, algebraic formulations that he had used as = grammatical=20 rules and where possible tried to improve upon them. A great deal of = fervent=20 grammatical research took place between the fourth century B.C and the = fourth=20 century A.D. and culminated in the seminal work, the Vaiakyapadiya by=20 Bhartrhari. Little was done subsequently to advance the study of syntax, = until=20 the so-called "New Grammarian" school appeared in the early part of the=20 sixteenth century with the publication of Bhattoji Dikshita's=20 Vaiyakarana-bhusanasara and its commentary by his relative Kaundabhatta, = who=20 worked from Benares. Nagesha (1730-1810) was responsible for a major = work, the=20 Vaiyakaranasiddhantamanjusa, or Treasury of dejinitive statements of=20 grammarians, which was condensed later into the earlier described work. = These=20 books have not yet been translated.

The reasoning of these authors is couched = in a=20 style of language that had been developed especially to formulate = logical=20 relations with scientific precision. It is a terse, very condensed form = of=20 Sanskrit, which paradoxically at times becomes so abstruse that a = commentary is=20 necessary to clarify it.

One of the main differences between the = Indian=20 approach to language analysis and that of most of the current linguistic = theories is that the analysis of the sentence was not based on a = noun-phrase=20 model with its attending binary parsing technique but instead on a = conception=20 that viewed the sentence as springing from the semantic message that the = speaker=20 wished to convey. In its origins, sentence description was phrased in = terms of a=20 generative model: From a number of primitive syntactic categories = (verbal=20 action, agents, object, etc.) the structure of the sentence was derived = so that=20 every word of a sentence could be referred back to the syntactic input=20 categories. Secondarily and at a later period in history, the model was = reversed=20 to establish a method for analytical descriptions. In the analysis of = the Indian=20 grammarians, every sentence expresses an action that is conveyed both by = the=20 verb and by a set of "auxiliaries." The verbal action (Icriyu- "action" = or=20 sadhyu-"that which is to be accomplished,") is represented by the verbal = root of=20 the verb form; the "auxiliary activities" by the nominals (nouns, = adjectives,=20 indeclinables) and their case endings (one of six).

The meaning of the verb is said to be = both vyapara=20 (action, activity, cause), and phulu (fruit, result, effect). = Syntactically, its=20 meaning is invariably linked with the meaning of the verb "to do". = Therefore, in=20 order to discover the meaning of any verb it is sufficient to answer the = question: "What does he do?" The answer would yield a phrase in which = the=20 meaning of the direct object corresponds to the verbal meaning. For = example, "he=20 goes" would yield the paraphrase: "He performs an act of going"; "he = drinks":=20 "he performs an act of drinking," etc. This procedure allows us to = rephrase the=20 sentence in terms of the verb "to do" or one of its synonyms, and an = object=20 formed from the verbal root which expresses the verbal action as an = action noun.=20 It still leaves us with a verb form ("he does," "he performs"), which = contains=20 unanalyzed semantic information This information in Sanskrit is = indicated by the=20 fact that there is an agent who is engaged in an act of going, or = drinking, and=20 that the action is taking place in the present time.

Rather that allow the agent to relate to = the syntax=20 in this complex, unsystematic fashion, the agent is viewed as a one-time = representative, or instantiation of a larger category of "Agency," which = is=20 operative in Sanskrit sentences. In turn, "Agency" is a member of a = larger class=20 of "auxiliary activities," which will be discussed presently. Thus = Caitra is=20 some Caitral or instance of Caitras, and agency is hierarchically = related to the=20 auxiliary activities. The fact that in this specific instance the agent = is a=20 third person-singular is solved as follows: The number category = (singular, dual,=20 or plural) is regarded as a quality of the Agent and the person category = (first,=20 second, or third) as a grammatical category to be retrieved from a = search list,=20 where its place is determined by the singularity of the = agent.

The next step in the process of isolating = the=20 verbal meaning is to rephrase the description in such a way that the = agent and=20 number categories appear as qualities of the verbal action. This = procedure=20 leaves us with an accurate, but quite abstract formulation of the = scntcnce: (3)=20 "Caitra is going" (gacchati caitra) - "An act of going is taking place = in the=20 present of which the agent is no one other than Caitra qualified by=20 singularity." (atraikatvaavacchinnacaitraabinnakartrko vartamaanakaa- = liko=20 gamanaanukuulo vyaapaarah:) (Double vowels indicate = length.)

If the sentence contains, besides an = agent, a=20 direct object, an indirect object and/or other nominals that are = dependent on=20 the principal action of the verb, then in the Indian system these = nominals are=20 in turn viewed as representations of actions that contribute to the = complete=20 meaning of the sentence. However, it is not sufficient to state, for = instance,=20 that a word with a dative case represents the "recipient" of the verbal = action,=20 for the relation between the recipient and the verbal action itself = requires=20 more exact specification if we are to center the sentence description = around the=20 notion of the verbal action. To that end, the action described by the = sentence=20 is not regarded as an indivisible unit, but one that allows further=20 subdivisions. Hence a sentence such as: (4) "John gave the ball to Mary" = involves the verb Yo give," which is viewed as a verbal action composed = of a=20 number of auxiliary activities. Among these would be John's holding the = ball in=20 his hand, the movement of the hand holding the ball from John as a = starting=20 point toward Mary's hand as the goal, the seizing of the ball by Mary's = hand,=20 etc. It is a fundamental notion that actions themselves cannot be = perceived, but=20 the result of the action is observable, viz. the movement of the hand. = In this=20 instance we can infer that at least two actions have taken=20 place:

(a) An act of movement starting from the = direction=20 of John and taking place in the direction of Mary's hand. Its Agent is = "the=20 ball" and its result is a union with Mary's hand.

(b) An act of receiving, which consists = of an act=20 of grasping whose agent is Mary's hand.

It is obvious that the act of receiving = can be=20 interpreted as an action involving a union with Mary's hand, an = enveloping of=20 the ball by Mary's hand, etc., so that in theory it might be difficult = to decide=20 where to stop this process of splitting meanings, or what the semantic=20 primitives are. That the Indians were aware of the problem is evident = from the=20 following passage: "The name 'action' cannot be applied to the solitary = point=20 reached by extreme subdivision."

The set of actions described in (a) and = (b) can be=20 viewed as actions that contribute to the meaning of the total sentence, = vix. the=20 fact that the ball is transferred from John to Mary. In this sense they = are=20 "auxiliary actions" (Sanskrit kuruku-literally "that which brings = about") that=20 may be isolated as complete actions in their own right for possible = further=20 subdivision, but in this particular context are subordinate to the total = action=20 of "giving." These "auxiliary activities" when they become thus = subordinated to=20 the main sentence meaning, are represented by case endings affixed to = nominals=20 corresponding to the agents of the original auxiliary activity. The = Sanskrit=20 language has seven case endings (excluding the vocative), and six of = these are=20 definable representations of specific "auxiliary activities." The = seventh, the=20 genitive, represents a set of auxiliary activities that are not defined = by the=20 other six. The auxiliary actions are listed as a group of six: Agent, = Object,=20 Instrument, Recipient, Point of Departure, Locality. They are the = semantic=20 correspondents of the syntactic case endings: nominative, accusative,=20 instrumental, dative, ablative and locative, but these are not in exact=20 equivalence since the same syntactic structure can represent different = semantic=20 messages, as will be discussed below. There is a good deal of overlap = between=20 the karakas and the case endings, and a few of them, such as Point of = Departure,=20 also are used for syntactic information, in this case "because of". In = many=20 instances the relation is best characterized as that of the allo-eme=20 variety.

To illustrate the operation of this model = of=20 description, a sentence involving an act of cooking rice is often = quoted: (5)=20 "Out of friendship, Maitra cooks rice for Devadatta in a pot, over a=20 fire."

Here the total process of cooking is = rendered by=20 the verb form "cooks" as well as a number of auxiliary=20 actions:

1. An Agent represented by the person=20 Maitra

2. An Object by the = "rice"

3. An Instrument by the = "fire"

4. A Recipient by the person=20 Devadatta

5. A Point of Departure (which includes = the causal=20 relationship) by the "friendship" (which is between Maitra and=20 Devadatta)

6. The Locality by the = "pot"

So the total meaning of the sentence is = not=20 complete without the intercession of six auxiliary actions. The action = itself=20 can be inferred from a change of the condition of the grains of rice, = which=20 started out being hard and ended up being soft.

Again, it would be possible to atomize = the meaning=20 expressed by the phrase: "to cook rice": It is an operation that is not = a=20 unitary "process", but a combination of processes, such as "to place a = pot on=20 the fire, to add fuel to the fire, to fan", etc. These processes, = moreover, are=20 not taking place in the abstract, but they are tied to, or "resting on" = agencies=20 that are associated with the processes. The word used for "tied to" is a = form of=20 the verbal root a-sri, which means to lie on, have recourse to, be = situated on."=20 Hence it is possible and usually necessary to paraphrase a sentence such = as "he=20 gives" as: "an act of giving residing in him." Hence the paraphrase of = sentence=20 (5) will be: (6) "There is an activity conducive to a softening which is = a=20 change residing in something not different from rice, and which takes = place in=20 the present, and resides in an agent not different from Maitra, who is = specified=20 by singularity and has a Recipient not different from Devadatta, an = Instrument=20 not different from.. .," etc.

It should be pointed out that these = Sanskrit=20 Grammatical Scientists actually wrote and talked this way. The domain = for this=20 type of language was the equivalent of today's technical journals. In = their=20 ancient journals and in verbal communication with each other they used = this=20 specific, unambiguous form of Sanskrit in a remarkably concise=20 way.

Besides the verbal root, all verbs have = certain=20 suffixes that express the tense and/or mode, the person (s) engaged in = the=20 "action" and the number of persons or items so engaged. For example, the = use of=20 passive voice would necessitate using an Agent with an instrumental = suffix,=20 whereas the nonpassive voice implies that the agent of the sentence, if=20 represented by a noun or pronoun, will be marked by a nominative = singular=20 suffix.

Word order in Sanskrit has usually no = more than=20 stylistic significance, and the Sanskrit theoreticians paid no more than = scant=20 attention to it. The language is then very suited to an approach that = eliminates=20 syntax and produces basically a list of semantic messages associated = with the=20 karakas.

An example of the operation of this model = on an=20 intransitive sentence is the following:

(7) Because of the wind, a leaf falls = from a tree=20 to the ground."

Here the wind is instrumental in bringing = about an=20 operation that results in a leaf being disunited from a tree and being = united=20 with the ground. By virtue of functioning as instrument of the = operation, the=20 term "wind" qualifies as a representative of the auxiliary activity=20 "Instrument"; by virtue of functioning as the place from which the = operation=20 commences, the "tree" qualifies to be called "The Point of Departure"; = by virtue=20 of the fact that it is the place where the leaf ends up, the "ground" = receives=20 the designation "Locality". In the example, the word "leaf" serves only = to=20 further specify the agent that is already specified by the nonpassive = verb in=20 the form of a personal suffix. In the language it is rendered as a = nominative=20 case suffix. In passive sentences other statements have to be made. One = may=20 argue that the above phrase does not differ in meaning from "The wind = blows a=20 leaf from the tree," in which the "wind" appears in the Agent slot, the = "leaf"=20 in the Object slot. The truth is that this phrase is transitive, whereas = the=20 earlier one is intransitive. "Transitivity" can be viewed as an = additional=20 feature added to the verb. In Sanskrit this process is often = accomplished by a=20 suffix, the causative suffix, which when added to the verbal root would = change=20 the meaning as follows: "The wind causes the leaf to fall from the = tree," and=20 since English has the word "blows" as the equivalent of "causes to fall" = in the=20 case of an Instrument "wind," the relation is not quite transparent. = Therefore,=20 the analysis of the sentence presented earlier, in spite of its manifest = awkwardness, enabled the Indian theoreticians to introduce a clarity = into their=20 speculations on language that was theretofore un- available. Structures = that=20 appeared radically different at first sight become transparent = transforms of a=20 basic set of elementary semantic categories.

It is by no means the case that these = analyses have=20 been exhausted, or that their potential has been exploited to the full. = On the=20 contrary, it would seem that detailed analyses of sentences and = discourse units=20 had just received a great impetus from Nagesha, when history intervened: = The=20 British conquered India and brought with them new and apparently = effective means=20 for studying and analyzing languages. The subsequent introduction of = Western=20 methods of language analysis, including such areas of research as = historical and=20 structural linguistics, and lately generative linguistics, has for a = long time=20 acted as an impediment to further research along the traditional ways. = Lately,=20 however, serious and responsible research into Indian semantics has been = resumed, especially at the University of Poona, India. The surprising=20 equivalence of the Indian analysis to the techniques used in = applications of=20 Artificial Intelligence will be discussed in the next = section.

Equivalence

A comparison of the theories discussed in = the first=20 section with the Indian theories of sentence analysis in the second = section=20 shows at once a few striking similarities. Both theories take extreme = care to=20 define minute details with which a language describes the relations = between=20 events in the natural world. In both instances, the analysis itself is a = map of=20 the relations between events in the universe described. In the case of = the=20 computer-oriented analysis, this mapping is a necessary prerequisite for = making=20 the speaker's natural language digestible for the artificial processor; = in the=20 case of Sanskrit, the motivation is more elusive and probably has to do = with an=20 age-old Indo-Aryan preoccupation to discover the nature of the reality = behind=20 the the impressions we human beings receive through the operation of our = sense=20 organs. Be it as it may, it is a matter of surprise to discover that the = outcome=20 of both trends of thinking-so removed in time, space, and culture-have = arrived=20 at a representation of linguistic events that is not only theoretically=20 equivalent but close in form as well. The one superficial difference is = that the=20 Indian tradition was on the whole, unfamiliar with the facility of = diagrammatic=20 representation, and attempted instead to formulate all abstract notions = in=20 grammatical sentences. In the following paragraphs a number of the = parallellisms=20 of the two analyses will be pointed out to illustrate the equivalence of = the two=20 systems.

Consider the sentence: "John is going." = The=20 Sanskrit paraphrase would be

"An Act of going is taking place in which = the Agent=20 is 'John' specified by singularity and masculinity."

If we now turn to the analysis in = semantic nets,=20 the event portrayed by a set of triples is the = following:

1. "going events, instance, go (this = specific going=20 event)"

2. "go, agent, John"

3. "go, time, present."

The first equivalence to be observed is = that the=20 basic framework for inference is the same. John must be a semantic = primitive, or=20 it must have a dictionary entry, or it must be further represented (i.e. = "John,=20 number, 1" etc.) if further processing requires more detail (e.g. "HOW = many=20 people are going?"). Similarly, in the Indian analysis, the detail = required in=20 one case is not necessarily required in another case, although it can be = produced on demand (if needed). The point to be made is that in both = systems, an=20 extensive degree of specification is crucial in understanding the real = meaning=20 of the sentence to the extent that it will allow inferences to be made = about the=20 facts not explicitly stated in the sentence

3D"Sanskrit

The basic crux of the equivalence can be=20 illustrated by a careful look at sentence (5) noted in Part=20 II.

"Out of friendship, Maitra cooks rice for = Devadatta=20 in a pot over a fire "

The semantic net is supplied in Figure 5. = The=20 triples corresponding to the net are:

cause, event, = friendship

friendship, objectl, = Devadatta

friendship, object2, = Maitra

cause, result cook

cook, agent, Maitra

cook, recipient, = Devadatta

cook, instrument, fire

cook, object, rice

cook, on-lot, pot.

The sentence in the Indian analysis is = rendered as=20 follows:

The Agent is represented by Maitra, the = Object by=20 "rice," the Instrument by "fire," the Recipient by "Devadatta," the = Point of=20 Departure (or cause) by "friendship" (between Maitra and Devadatta), the = Locality by "pot."

Since all of these syntactic structures = represent=20 actions auxiliary to the action "cook," let us write %ook" uext to each = karakn=20 and its sentence representat(ion:

cook, agent, Maitra

cook, object, rice

cook, instrument, fire

cook, recipient, = Devadatta

cook, because-of, = friendship

friendship, Maitra, = Devadatta

cook, locality, pot.

The comparison of the analyses shows that = the=20 Sanskrit sentence when rendered into triples matches the analysis = arrived at=20 through the application of computer processing. That is surprising, = because the=20 form of the Sanskrit sentence is radically different from that of the = English.=20 For comparison, the Sanskrit sentence is given here: Maitrah: sauhardyat = Devadattaya odanam ghate agnina pacati.

Here the stem forms of the nouns are:=20 Muitra-sauhardya- "friendship," Devadatta -, odana- "gruel," ghatu- = "pot," agni-=20 "fire' and the verb stem is paca- "cook". The deviations of the stem = forms=20 occuring at the end of each word represent the change dictated by the = word's=20 semantic and syntactic position. It should also be noted that the Indian = analysis calls for the specification of even a greater amount of = grammatical and=20 semantic detail: Maitra, Devadatta, the pot, and fire would all be said = to be=20 qualified by "singularity" and "masculinity" and the act of cooking can=20 optionally be expanded into a number of successive perceivable = activities. Also=20 note that the phrase "over a fire" on the face of it sounds like a = locative of=20 the same form as "in a pot." However, the context indicates that the=20 prepositional phrase describes the instrument through which the heating = of the=20 rice takes place and, therefore, is best regarded as an instrument = semantically.=20 cause

Of course, many versions of semantic nets = have been=20 proposed, some of which match the Indian system better than others do in = terms=20 of specific concepts and structure. The important point is that the same = ideas=20 are present in both traditions and that in the case of many proposed = semantic=20 net systems it is the Indian analysis which is more = specific.

A third important similarity between the = two=20 treatments of the sentence is its focal point which in both cases is the = verb.=20 The Sanskrit here is more specific by rendering the activity as a = "going-event",=20 rather than "ongoing." This procedure introduces a new necessary level = of=20 abstraction, for in order to keep the analysis properly structured, the = focal=20 point ought to be phrased: "there is an event taking place which is one = of=20 cooking," rather than "there is cooking taking place", in order for the = computer=20 to distinguish between the levels of unspecified "doing" (vyapara) and = the=20 result of the doing (phala).

A further similarity between the two = systems is the=20 striving for unambiguity. Both Indian and AI schools en-code in a very = clear,=20 often apparently redundant way, in order to make the analysis accessible = to=20 inference. Thus, by using the distinction of phala and vyapara, = individual=20 processes are separated into components which in term are decomposable. = For=20 example, "to cook rice" was broken down as "placing a pot on the fire, = adding=20 fuel, fanning, etc." Cooking rice also implies a change of state, = realized by=20 the phala, which is the heated softened rice. Such specifications are = necessary=20 to make logical pathways, which otherwise would remain unclear. For = example,=20 take the following sentence: 3D"Rice

"Maitra cooked rice for Devadatta who = burned his=20 mouth while eating it."

The semantic nets used earlier do not = give any=20 information about the logical connection between the two clauses. In = order to=20 fully understand the sentence, one has to be able to make the inference = that the=20 cooking process involves the process of "heating" and the process of = "making=20 palatable." The Sanskrit grammarians bridged the logical gap by the = employment=20 of the phalu/ vyapara distinction. Semantic nets could accomplish the = same in a=20 variety of ways:

1. by mapping "cooking" as a change of = state, which=20 would involve an excessive amount of detail with too much compulsory=20 inference;

2. by representing the whole statement as = a cause=20 (event-result), or

3. by including dictionary information = about=20 cooking. A further comparison between the Indian system and the theory = of=20 semantic nets points to another similarity: The passive and the active=20 transforms of the same sentence are given the same analysis in both = systems. In=20 the Indian system the notion of the "intention of the speaker" = (tatparya,=20 vivaksa) is adduced as a cause for distinguishing the two transforms=20 semantically. The passive construction is said to emphasize the object, = the=20 nonpassive emphasizes the agent. But the explicit triples are not = different.=20 This observation indicates that both systems extract the meaning from = the=20 syntax.

Finally, a point worth noting is the = Indian=20 analysis of the intransitive phrase (7) describing the leaf falling from = the=20 tree. The semantic net analysis resembles the Sanskrit analysis = remarkably, but=20 the latter has an interesting flavor. Instead of a change from one = location to=20 another, as the semantic net analysis prescribes, the Indian system = views the=20 process as a uniting and disuniting of an agent. This process is = equivalent to=20 the concept of addition to and deletion from sets. A leaf falling to the = ground=20 can be viewed as a leaf disuniting from the set of leaves still attached = to the=20 tree followed by a uniting with (addition to) the set of leaves already = on the=20 ground. This theory is very useful and necessary to formulate changes or = statements of state, such as "The hill is in the = valley."

In the Indian system, inference is very = complete=20 indeed. There is the notion that in an event of "moving", there is, at = each=20 instant, a disunion with a preceding point (the source, the initial = state), and=20 a union with the following point, toward the destination, the final = state. This=20 calculus-like concept fascillitates inference. If it is stated that a = process=20 occurred, then a language processor could answer queries about the state = of the=20 world at any point during the execution of the = process.

As has been shown, the main point in = which the two=20 lines of thought have converged is that the decomposition of each prose = sentence=20 into karalca-representations of action and focal verbal-action, yields = the same=20 set of triples as those which result from the decomposition of a = semantic net=20 into nodes, arcs, and labels. It is interesting to speculate as to why = the=20 Indians found it worthwhile to pursue studies into unambiguous coding of = natural=20 language into semantic elements. It is tempting to think of them as = computer=20 scientists without the hardware, but a possible explanation is that a = search for=20 clear, unambigous understanding is inherent in the human being.=20

Let us not forget that among the great=20 accomplishments of the Indian thinkers were the invention of zero, and = of the=20 binary number system a thousand years before the West re-invented them.=20

$3D"Zero$ $3D"Binary$

Their analysis of language casts doubt on = the=20 humanistic distinction between natural and artificial intelligence, and = may=20 throw light on how research in AI may finally solve the natural language = understanding and machine translation problems.

References
Bhatta, Nagesha = (1963)=20 Vaiyakarana-Siddhanta-Laghu-Manjusa, Benares (Chowkhamba Sanskrit Series = Office).

Nilsson, Nils J. Principles of Artificial = Intelligence. Palo Alto: Tioga Publishing Co

Bhatta, Nagesha (1974) = Parama-Lalu-Manjusa Edited=20 by Pandit Alakhadeva Sharma, Benares (Chowkhambha Sanskrit Series=20 Office).

Rumelhart, D E. & D A. Norman (1973) = Active=20 Semantic Networks as a model of human memory. IJCAI.

Wang, William S-Y (1967) "Final = Administrative=20 Report to the National Science Foundation." Project for Machine = Translation.=20 University of California, Berkeley. (A biblzographical summary of work = done in=20 Berkeley on a program to translate Chinese.)

[THE AI MAGAZINE Spring, = 1985=20 #39]

Artificial=20 Intelligence & Sanskrit top

Science=20 Index=20

Vedic Science

Sanskrit & Artificial Intelligence = =97 NASA
Knowledge=20 Representation in Sanskrit and Artificial Intelligence

Abstract

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Artificial Intelligence =97Sanskrit=97 The Age of = Information =97=20 NASA =97 Knowledge Representation

Science Article Links

Vedic Science

Sanskrit & Artificial Intelligence = =97 NASAKnowledge=20 Representation in Sanskrit and Artificial Intelligence

Abstract

Equivalence

Artificial Intelligence =97Sanskrit=97 The Age of = Information =97=20 NASA =97 Knowledge Representation

Science Article Links

Sanskrit & Artificial Intelligence = =97 NASA
Knowledge=20 Representation in Sanskrit and Artificial Intelligence