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11. The future of MT

(1) Machine translation software will be on a word processor or on a laptop personal computer in the near future, and machine translation will become available everywhere - at home, in the office, and at school. In such a situation, a system will be adapted quickly to individual user needs by the learning mechanism in the system.
(2) Another direction is network access to a big MT system from a home computer. Users in this category may not use MT systems regularly, and therefore particular care must be taken to develop user-friendly interfaces.
(3) Present-day MT systems have a definite limitation in translation quality because they are based on the compositionality principle. Anaphora and ellipsis cannot be handled well because the systems don't recognize relationships between sentences. Much ambitious research must be performed in the future and include that on natural language understanding and more elaborate contrastive linguistic studies.
(4) Multilingual machine translation systems must be developed not only for European languages but also for Asian languages and other languages worldwide.
(5) Machine translation must be introduced into information retrieval systems and database systems so that people all over the world can have easy access to any information sources in the world.
(6) Machine translation must be introduced for the daily news transmitted via computer network and also for electronic mail systems, which are becoming more and more popular and represent a convenient way of communication.
(7) Speech translation research must be performed. At the ATR, the Interpreting Telephony Research Institute in Japan, research has been going on since 1986 for Japanese and English. It is highly recommended that other countries start similar research projects.
(8) International cooperation is essential in machine translation research and development. Dictionaries must be exchanged, and contrastive studies of languages are to be promoted as cooperative research works among different countries. Such activities must be supported continuously for a long time, for example 10 or 15 years, because language is a very difficult objective to attack. Agreement must be reached at the governmental level and Unesco on such international cooperative research.

The new world of computing: The sub-language paradigm


Abstract
1. Prologue
2. Obstacles to the development of the telephone-computer
3. Sub-language: a new paradigm
4. The implementation of sub-languages
5. The creation and basing of sub-languages
6. Networking in the telephone-computer era
7. All of the world's information
8. The new world of computing applications development environment
9. Toward an efficient organization of the software and data provider industry
10. The vision and the realization
11. Epilogue
Notes


Bozena Henisz Thompson and Frederick B. Thompson

Abstract

Following a brief discussion of obstacles to the introduction of a "telephone-computer era" (based on the use of a combination of the telephone, personal computer, workstation, and television set), the "sub-language" concept is presented, this being a form of communication that is related to natural language but is domain specific. The processes of implementing sub-languages on the computer are described. Treated thereafter are the creation and basing of sub-languages and the ways in which networking is accomplished. Finally, the relevant software development environment is discussed and suggestions made for the organization of a software and data provider industry that could stimulate the arrival of the new "telephone-computer era."

1. Prologue

We are witnessing one of history's major technological events: the advance of the telephone-computer era. Over a number of years, we have directed our research toward the solution to the problems of this coming age. The results of this research are presented here. However, it is not enough to put down some concepts from which a solution may be implied. The solution therefore is also in the form of a fully implemented system that now exists as a commercial prototype ready for product development - the New World of Computing system.

2. Obstacles to the development of the telephone-computer

The next decade will see the telephone, personal computer, workstation, and television set combined into a single, ubiquitous instrument - the telephone-computer. The telephone-computer will cause a rapid, widespread acceleration in the use of information processing and telecommunications. As a result of this major development, the market for both computer hardware and software will rapidly expand in both quantity and variety. This market will soon far exceed the current market for personal computers, workstations, and large transaction processors.

Current hardware capabilities are already adequate for this development: 30 MIP processing chips, voice digitizing, image processing and communication chips, 8 megabyte main memories, and 100+ megabyte peripheral memories are quite adequate for the great bulk of processing to be done. 144 K bits per second, error free, and soon 1,500 K bits per second, telecommunications, with packet switching, are now becoming available; capabilities can be expected to stay well ahead of foreseeable needs. New technologies, such as flat screens, and parallel processing chips will all enhance this radical change in the human-computer interface.

What will the era of the telephone-computer be like? This question has been the focus of our research over a number of years. One thing is clear: in the confluence of computer technology and telecommunications technology, we are witnessing one of history's major advances in human communication.

Industry is ill-prepared for this rapid acceleration of the information technologies. There are dislocations in the current software industry that work against the full development of the telephone-computer. One major symptom of these dislocations is the high cost of software development. Industry is acutely aware of these symptoms, as evidenced by their concern with "open systems" and "software engineering" approaches. However, the roots of these problems lie elsewhere. In this paper we will identify these roots and an approach that substantially corrects them.

As industry moves into this period of accelerating change and expanding market opportunity, management- indeed the industry as a whole - needs a coherent set of concepts that can provide the perspective required for intelligent decision-making. At this point in time, there is an almost total lack of sensible, down-to-earth concepts on which to develop an understanding and a strategy for what is taking place. Lacking perspective, managers in the computer industry are preoccupied with tactical questions and short-range considerations.

The artificial intelligence paradigm has distracted us and has proven to be inadequate. The successes of UNIX, on the one hand, and the Macintosh computer interface, on the other, have led industry into espousing the minimalist philosophy of the computer as an applications independent tool kit. The situation was stated succinctly by Dr. Robert W. Lucky in his capacity as Annenberg Distinguished Lecturer, the University of Southern California, on 22 January 1990.¹ After surveying the astounding advances in telecommunications resulting from the development of digital switching and optical fibre technologies, he asked the rhetorical question: "What are we going to do with this gigabyte? To be honest with you, nobody knows."

He went on to state that there is a total lack of leadership to carry us into the emerging telephone-computer era. In parallel with the vacuum in the conceptual area, he pointed out that the legal position of the Local Area Telephone Companies has worked against any telephone company taking a leadership role.

A new paradigm is needed that puts into proper perspective the role of the computer in human communications.

3. Sub-language: a new paradigm

We present here a simple, basic concept, that of a "sub-language." A sub-language is a form of human communication that is domain specific, appropriate to that domain, and, consequently, highly efficient. Using this concept, we put forward a new paradigm for human information processing and communication. We then use this paradigm to lay out the new world of computing that will characterize the telephone-computer era.

We have learned to impose structure on the jumble of our moment-to-moment experiences so as to create order and provide perspective. In the words of William James:

Is not the sum of your actual experience taken at this moment and impartially added together an utter chaos? The strains of my voice, the lights and shades inside the room and out, the murmur of the wind, the ticking of the clock, the various organic feelings you may happen individually to possess, do these make a whole at all? . . . We break it: we break it into histories, and we break it into arts, and we break it into sciences; and then we begin to feel at home.... The intellectual life of a man consists almost wholly in his substitution of a conceptual order for the perceptual order in which his experience originally came.²

It is in terms of this conceptual order that our world becomes comprehensible.

It is the infinitely variable expressions of language that give tangible form to our own immediate view of the world and by which we share that view with others. It should be no surprise to find human language playing the central role in leading to an understanding of information processing. The mechanisms of language are precisely the tools we need and use to express the recursive structures we impose on our experience. It is these mechanisms of language that we universally share that form the basis of communication.

What is this "natural language" that we use? The notion of natural language has played a useful role in linguists' development of a general understanding of human communication, in the codification and maintenance of purity of national languages, and the training of language teachers. Language, in the sense used by linguists, might more properly be thought of as an integrated family of linguistic mechanisms, often expressible as grammar rules. The phenomenon of information processing and communications, although exhibiting in a given cultural community the adherence to such syntactic forms, also has features better characterized, we believe, by the notion of "sub-language." Current literature often refers to a person's mental awareness of the world as one's "cognitive model." But it is not a single model; it is a large family of interrelated, comparable models - the many alternatives that we visualize and choose among. The logician would refer to these as the model theoretic counterpart of our sub-language; and indeed, abstractly, the model theoretic and the linguistic representations are quite equivalent. We do not wish to imply that we "think linguistically," as an alternative to "thinking in terms of a cognitive model." Rather, it is simply a more useful paradigm for the consideration of the role of the computer, a case that we intend to make in this paper. The linguistic formulation, we feel, grasps much more clearly the characteristics of our ongoing cognitive processes.

In dealing with their immediate task environment, people narrow their considerations by making judgements of relevance, value, and task effectiveness - judgements that are characteristically human. The results of these judgements take concrete form in the sub-languages we use both in communicating within our task group and in our own internal thought processes. A moment's introspection makes it clear that as we move about from one task to another during a busy day we change from one sub-language to another as our attention is drawn from one domain of activity to another. These sub-languages differ in vocabulary, often in their cryptic syntax, and even in the meanings of the same words. Their only commonality is their basic linguistic structure.

Consider the sentences in figure 1 entered by the trust officer of a bank in his ongoing dialogue with his computer. Does this look like English? It is not. Surely it is a sub-language of English, one that has been geared to the concerns of the trust officer. In such a defined context, the phrasing is no longer ambiguous or indecipherable.

The concerns of a human individual engaged in a specific task environment can be characterized by that person's immediate sub-language. The essential characteristic of a well functioning team is their common sub-language. The stability of a given sub-language is found in the stability of the task we undertake. When we return again and again to a task, and to that group in which we interact in conducting that task, it is the sub-language that codifies and externalizes our ongoing considerations. And it is the ongoing, ubiquitous changes in that sub-language that track our decision-making processes.

As an illustration, consider a particular work environment, say that of a person working as secretary for an industrial manager. One aspect of that person's environment is their typewriter. The technology of the typewriter keyboard has not changed in many years, even though a more efficient layout of the keys is known. The reasons for this stability are not hard to envision - the keyboard does not change because of the strong social inertia resulting from so many people having been trained on the existing one. There are many other aspects of the typing, filing, and sending of letters, reports, etc., where there are both physical and social inertia that mitigate against change in many aspects of the secretary's concern. The moment to moment sub-language of such a person is constantly shifting as a needed address must be found, a letter retrieved from a file, a phone call answered. But a part of all of these sub-languages remains essentially constant - that part related to the mechanics of typing, phoning, filing, where the physical and social inertia are high. This part can itself be characterized as a formal language. It is precisely these highly stable sub-languages that can economically be built into computer systems. Word processors are an ideal example of how the inertia of a significant part of the secretarial world can be exploited.

• Which of Bob Moore's equities changed by more than five percent in the last two weeks?

• How many high-tech shares does he own?

• What are our short-term projections for GM and DetEd?

Figure 1

This illustration, concerning word processors, bears greater scrutiny. When a team is working on a project, there are at any given time a number of aspects that are undergoing change, and the rapidity of this change results in uncertainties and ambiguities in the sub-language that characterizes their interactions. Each of the participants has their own sub-language related to the common task but also containing the expertise and personal insights the individual brings to the common effort. But it is essential to the effective functioning of the team that they share completely and unambiguously and tacitly a sub-language that establishes the basis for their intercommunication. It is this that is the team's sub-language. Relative to their many interactions- the sharing of insights, the settling of differing ways to approach a problem, etc. - this team sub-language changes only slowly. And these changes result directly from interventions of the team itself. A word processor obviously does not comprehend the entire sub-language of a busy secretary. But it is a stable part of the secretary's rapidly changing sub-language.

A useful analogy is to the layout of a mountainous terrain. Suppose all sub-languages were spread out over a broad area, and that the altitude of this terrain at any point was some measure of the relevance of the associated sub-language to the task at hand. The landscape would in general consist of a tall mesa whose top was quite flat except for a small hill. As time went by, the mesa would move almost imperceptibly, while the hillock would be seen to shift about, in almost constant motion, as the concerns of the moment shifted from one situation to the next.

Consider a team, working on a common design task. If one were to ask them what they were doing, they would say "designing a...." From our perspective, however, their sole task is the maintenance of the underlying team sub-language. The completion of their task is marked by their agreement that this sub-language is now ready to be passed on to those who will implement their design. Their common sub-language will, by that time, have evolved into one containing the design drawings, part tables, and specification lists in forms they know to meet the conventions established for transmittal to the industrial engineers who will further prepare them to go to tooling and the production floor. These conventions are characteristic of the hierarchy of sub-languages that characterize interactions in an organization.

There is one area where the computerization of sub-languages is already highly developed and sophisticated, namely programming languages. The stability of the Von Neumann architecture has resulted in an evolutionary development of sub-languages that exploit this stability. We will say that the computer "understands" a sub-language to mean precisely the same as when we say a computer understands a programming language. Namely, it carries out instructions in the way they were intended to be carried out, whether in the sub-language of a programmer or the sub-language of a professional when referring to work-related matters. Stable, domain-specific sub-languages, from simple word processors to the cryptic, icon-oriented yet highly sophisticated sub-language of a NASA space flight control room, can be handled by a computer as easily as any traditional programming language. Computers can be programmed to understand the highly idiosyncratic, often cryptic sub-languages of individuals and teams from all walks of life.

The academic disciplines of linguistics, foundations of mathematics, and computer science provide firm theoretical underpinnings for the study and computer implementation of sub-languages. A brief overview of these underpinnings reveals in sharp focus the full sub-language paradigm. The concept of "sub-language" is abstractly equivalent to the concepts of "recursive function" and "Turing machine." Thus our "sub-language" paradigm is equivalent to Church's thesis that human information processing can be characterized by these formalisms.

To give utmost precision to this statement, we restate this paradigm in terms of one of the above formalisms. Turing machines can be enumerated, i.e., we can speak of the ith Turing machine, Ti. A Universal Turing machine, Tu, is such that given any argument n, Tu(i,n) = Ti(n); thus a universal Turing machine can simulate any Turing machine, provided it is given the proper index. We are indeed Universal Turing machines, but with a Demon D. Having observed n, our Demon selects that Turing machine that is most informing, and Tu(D(n),n) becomes our cognitive model. In this formalism, the sub-language paradigm is equivalent to saying that at any instant our thought processes can be characterized as a Turing machine; but the selection of what Turing machine is a non-computable process, characteristically human.

The sub-language paradigm can also be considered as the integration of two other well-established paradigms of computer science, namely object-oriented programming and compositional semantics. Approaching this relationship from the object-oriented perspective, take the object classes as "parts of speech," the "semantic categories" of Tarski's seminal paper³ that established modern mathematical linguistics. We note the clear tie to consideration of data structures. In the terminology of compositional - or more generally procedural semantics, a sub-language is defined by its "rules of grammar," each of which is associated with a semantic procedure. The implementation of these semantic procedures on the computer is in terms of the processes encapsulated in the object classes associated with the parts of speech occurring in the syntax rule. This point of view yields an elegant formulation of the "sub-language" notion: Let the processes and memory structures of a given object-oriented programming environment be implemented in "hardware," then the "sub-language" becomes the "machine language" of the resulting computer. In this form, sub-language is abstractly equivalent to "computer"; that is, the set of all "sub-languages" coincides with the set of all machine languages of computers.

The paradigm for human information processing can now be stated:

It is the constant re-evaluation and adjustment of the relevant view that characterizes human information processing. A succinct expression of such a view is as a formal language. When there are strong social and physical inertia in an area of broad concern, a part of the sub-languages characterizing those concerns stabilizes. For these stable areas, it is economically expedient to develop computer systems that can understand these sub-languages. When, in some area, these stabilities dissipate and others arise, it is only human intervention that can maintain their relevance and effectiveness.

A computer can "understand" a given task-specific sub-language far beyond its use as a simple query language to a database. Consider a middle-level manager in a large engineering establishment (see figure 2). He changes the estimated time of completion of one of the tasks for which he is responsible by typing instructions to his computer; the computer responds by carrying out the indicated actions. The sub-language of engineering management is thus "understood" by the computer, just as the manager would expect a staff assistant to have responded in a pre-computer era. The computer then becomes an instantaneous link, conveying the relevant implications of this simple change to wide-ranging concerns across the engineering floor. The computer is seen here in its true identity, as a powerful communications device. A brief, curt word to the computer, in the same jargon that has been developed by the management team, is enough to elicit a complex computer response, which may include composing and sending messages or controlling equipment. However, as the task develops, there will always be new instructions for the computer; therefore, there is a need to fall back on longer sentences and more complex commands, using, of course, the syntax and vocabulary of our own sub-language.

4. The implementation of sub-languages

How are sub-languages implemented in the computer? Members of one class of sub-languages are already implemented in computers, namely programming languages. How are they currently implemented? A compiler is written that embodies both the syntax of the language and the semantics. The compiler accepts a sentence of the language and returns a single, machine language program. When used in interactive mode, this program is then executed. That is, the abstract computer that understands the programming language consists of a hardware computer with its own machine language and the compiler, which translates the programming language into machine language. To change the programming language, one rewrites the compiler. There are compelling reasons why this is a bad technology for implementing sub-languages, including programming languages. Before discussing these reasons, we present here a radically different technology.

The manager enters: "Task G will be delayed 10 days."

The computer:

1. changes appropriately the data base entry for the duration of task G;
2. recomputes a Pert chart for the entire project;
3. for those tasks that will experience a significant delay, generates e-mail to the affected managers, identifying the cause and potential consequences of the delay;
4. sends any changes in critical path tasks to the Project Manager.

Figure 2

Let the computer be a Universal Language Processor (a hardware computer with a universal language processor replacing the compiler of a particular language, if you like). It operates in two modes:

  • (1) It accepts, one at a time, the rules of grammar and their associated semantic procedures that define the sub-language, building them into its internal grammar table.
    (2) It accepts an input sentence, parses it according to the grammar, uses the resulting parsing graph to compose the associated semantic procedures, evaluates them, outputs the result, and cycles.
  • Figure 3

    A typical Rule of Grammar (as understood by the computer):

    RULE
    >Syntax :<noun_phrase> =><adjective>" "<noun_phrase>
    >Semantics: POST adj_mod_proc

    Thus it is a simple, straightforward implementation of compositional semantics.

    A little insight into what is going on here will be useful in understanding the power of this paradigm. Sub-languages are defined to the computer in terms of grammar rules, consisting of a syntactic aspect and an associated semantic procedure. An example of such a rule is shown in figure 3. Given the constituents of a meaningful phrase - for example: "government" and "contracts" - the semantic procedure goes to the two associated data files and produces the "meaning" of the entire phrase: "government contracts." The role of syntax is to show how words and phrases can be combined into meaningful statements. Once the syntactic structure of a sentence is seen, the associated semantic procedures can be composed appropriately. The rules of grammar, along with the corresponding semantic procedures, constitute the building blocks. Each of these rules is implemented as a separate unit. The syntax of a sentence provides the plan for combining these building blocks into the complex meaning of the entire sentence. Thus the individual semantic procedures can be efficiently composed in innumerable ways to produce the needed answers to immediate user concerns.

    (The first question that will come to the mind of a knowledgeable computer person is the effect of such an architecture on response time. Let us deal with this immediately. In our current implementation of this architecture, against a moderate size database concerning ships and shipping [for computational linguists, this is the well-known DARPA "blue" file.], and using a sizable grammar, the parsing time for the following sentence: "What is the cargo type and destination of each ship whose port of departure was some Soviet port?" is about a tenth of a second; the through put time, including database access, is 8 seconds. The key to these response times lies in the fact that in such very high-level sub-languages, the object-class data structures and processes are highly optimized, so that in processing a sentence, one is composing a few highly optimized procedures.)

    The first thing to notice are the implications of the independence of the grammar rules - syntax and associated semantic procedures. As said above, in building a sub-language, rules are added one at a time. These same rule-adding utilities can obviously be used at any time to add an additional rule or, for example, a whole family of rules implementing a new object class. It is these same utilities that implement the user's ability to extend his own sub-language by definitions.

    An "insider's" problem is to determine how the great number of highly complex procedures that may all be needed at some time or another can be retained in a form that makes them available for rapid response to a query. One way that has proved particularly effective is to use "pages" in peripheral memory that are organized on the basis of semantic content. In response to a particular query, only those pages that are required are brought into main memory - whether they be database record, procedure, text, image, digitized voice, or other pages. Pages holding all manner of material are brought into the same paging area. Obviously, procedure pages require a modicum of run time binding, but since the number of paging slots is large, there is very little trashing of pages between main and peripheral memories.

    The information available to the computer is organized into a network of "nodes" and "links." The "nouns" of a sub-language point to certain of the nodes in this semantic net. The syntax rules also have a geometric interpretation in terms of the semantic net; they indicate how to move from one set of nodes to another. Thus the parser composes the path from the words in the initial expression of a question to the nodes constituting the desired answer. The information about a node is kept on a database record on one or more pages of peripheral memory.

    Organizing information in this way provides a highly efficient and flexible method for maintaining a rather shallow level of information organization (essentially equivalent to an entity-attribute database or relational database, plus inheritance). By linking such "database" records to more complex forms of representation (e.g., texts, pixel files, postscript files, engineering drawings) and by providing sophisticated semantic procedures that can exploit the additional complexities of these structures, the computer can give wide-ranging responses to highly complex technical questions. In the terminology of object-oriented programming, these database records constitute the object representations for the single all-encompassing object class, "noun." Any hierarchy of subclasses of objects may be created, such as "image noun," "matrix noun," "co-variance matrix noun," etc., with their associated processing procedures.

    A new object class can be easily implemented as a new subclass of the "noun" object class; when an instance of the new object class is created, first its record as an instance of "noun" is created, and then a link from this record to an instance of the data structure of the new class is added. As an example, suppose one were building a new sub-language to be used by the structural engineers in an aerospace company. Suppose the company already had a major investment in files of stress data and, say, FORTRAN procedures that processed these files. The new object class, a sub-object class of "noun," would be created whose associated data structure was that of the stress data files. Syntax rules for noun phrases that engineers commonly used in referring to the stress data would be added, their corresponding semantic procedures consisting largely of calls to the relevant FORTRAN routines. Such queries as: "Plot the stress against wing tip loading for both Model A12 and Model A14 wing aileron designs" would be immediately available.

    In today's highly visual world, sub-languages are seldom limited to written text. But how can this complete integration of media be implemented? Certainly the identification of the object class with its encapsulation of structure and process is a major step. Another step concerns the extended "alphabet" available to all sub-languages. All letters and characters of the usual alphabet as well as the entire extended ASCII character set; all graphic "events," such as clicks of the mouse and movements of the cursor; and all "interrupts" from internal and external sources (properly screened and identified) can be used in the input string that is fed to the language processor. (The computer, like human beings, has "fingers" for pointing and "intonation" and "gestures" it can use.) In this respect, all sub-languages have the same terminal vocabulary, namely this extended alphabet. Once this is established, grammar rules can supply the recursive, flexible link between the input string and the internal object classes. For example, one can at any time introduce a new icon, placing under it any sentence or phrase of the sub-language that is then evaluated in line whenever the icon is clicked during input of a query.

    In figure 4, an airline mechanic is seen working on the radar nose-cone of a Boeing 747 aircraft. He turns to his computer for detailed technical support. He has already entered information identifying the particular aircraft he is working on and has called for a display of the nose-cone area. The computer-generated photo image of the relevant area (plus an invisible back-plane drawing outlining all significant parts) provides a highly efficient medium for communication. For example, he may type "leak" and click his mouse on the image of the place he suspects is leaking oil. The computer may respond with the spoken word: "tighten" and blink the bolt it identified in its diagnosis as the probable cause of the leak. In response to a sparsely stated but technically involved question, the mechanic receives an immediately useful response that reflects a high degree of built-in understanding.

    In figure 5, a maintenance professional is entering instructions into his personal, completely mobile, telephone-computer. It eliminates any need for the usual truck-full of manuals. The professional's efficiency is greatly increased, since the computer tailors its responses to the specific installation. Astute use of hypermedia links from one data display to another quickly provides pathways to the details the professional really needs. References that establish context (e.g., "I am at . . ."), as well as pronouns and elliptic constructions (e.g., "What about the other connector?") play important roles in effective dialogue. Note that pointing to and blinking significant areas in pictures and drawings constitutes visual "pronouns" (e.g., "voltage 'there'?" or "tighten 'that'," ''[ show schematic icon] of 'that"').

    There is a leak here (pointing at the monitor}. Is this Shuttle cock tightly closed? (valve on monitor blinks) Yes. Check the connection here (arrow points to indicated point).

    Figure 4

    I am at 766 Oak Lane. Show me the electric panel wiring diagram.

    Figure 5

    Figure 6

    5. The creation and basing of sub-languages

    The typical industrial manager will have many sub-languages, for example:

    - schedules and deliverables
    - budgets and fiscal control
    - personnel assignments and administration
    - correspondence

    Underlying each of these, and a part of every sub-language, are the general dialect of the manager's natural language, a complete graphics package, text editor, electronic mail, voice messaging, etc. Once he has chosen to use any one of his sub-languages, all of these services will be immediately available; the manager will not be aware of which service a phrase of his query may have invoked as he proceeds in his normal way: "Send this draft budget to my section managers with the following message: '. . . (voice) . . ."'; "Schedule a meeting with them sometime on Wednesday afternoon."

    How are sub-languages created? Initially, there is one sub-language, BASE. It contains a limited dialect of English that is adequate to handle expressions concerning typical relational, or entity-attribute databases with inheritance. It also contains a graphics package, text editor, electronic mail, etc., as mentioned above. To create a new sub-language, say "Finances," one "bases" it on BASE: base Finances on BASE, or, for that matter, on any pre-existing sub-language that may be available. Then, choosing this new sub-language: enter Finances, one has all the capabilities of the based upon sub-language immediately available. One can then extend this new sub-language in many ways (these will be discussed below).

    In figure 6, engineering manager E.D. Moore creates a sub-language to share with his three subordinate managers. Now any of the four of them can use, modify, and extend this common sub-language "EngSec." Thus they jointly maintain a common, up-to-date view of their joint activities (e.g., preliminary designs, personal schedules). This is the significance of being able to "enter."

    Figure 7

    There is a strong asymmetric relationship between a sub-language and all of the sub-languages on which it is based, either directly or indirectly. Suppose one sub-language, "Accounting," is based on another, "Personnel Accounting": base Accounting on Personnel Accounting. Any changes in Personnel Accounting are immediately reflected in Accounting; however, Accounting can be changed in any way without affecting Personnel Accounting. This asymmetric relationship is characteristic of basing.

    In figure 7, showing the accounting sub-languages, the people in the Personnel Accounting Section are the only ones who are authorized to enter the Personnel Accounting sub-language; therefore, they are the only ones who can change it; the same holds for the Contracts Accounting and General Accounting sub-languages. Accounting is based on each of these three. No one is authorized to enter Accounting; therefore no one can make any changes in it. Of course, it is automatically always up to date with the latest data from Personnel Accounting, Contracts Accounting, and General Accounting.

    Appropriate managers are authorized to base on Accounting. One of the Department Manager's sub-languages is based on both Accounting and Production, and therefore always has available the very latest accounting information. The manager may well have had the application programmers add a number of grammar rules, graphic output formats, and icons, so that overviews of the complete operation are always readily available. These added facilities would only be available in this particular sub-language, but would always utilize the latest accounting and production data. A member of the manager's staff, looking into the possible change in the pricing structure for company products, could also base a staff study sub-language on Accounting, change many of the entries to values reflecting the new pricing structure, then examine the inferred results, and finally arrange appropriate graphics for a presentation (without, of course, affecting the Accounting sub-language at all). In figure 8, placing one sub-language above another indicates that the top one has been based upon the one immediately below.

    Figure 8


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