Y.

TECHNOLOGY

WHY COMPUTERSCAN'T OUTTHINK

THE EaPEK 19Programs called expert systems are being ballyhooed as the hottest technology around. Whileuseful for some tasks, the systems aren't as smart as they sound. We'll keep needing old-fashioned specialists whose intelligence isn't artificial. ■ by Tom Alexander

|XPERT SYSTEMS—computer pro- processesofhuman experts,andsome of the dollars to developing expertsystems. Th6*em grams that grew out of research in ar- newsoftware is being ballyhooedas smarter who see the technology as vastlyamplifyingB tificial intelligence—are suddenly the than humans. Planners in government, at the impact ofcomputers on societyare com-

Jflbiggest technologycraze since genet- giant corporations such as General Motors paring it to the invention of the printingie engineering.The programs aim to endow and Exxon, and at dozensof start-up compa- press or the steam engine.:omputers with the wit to mimic thethought nies have allocated hundreds of millions of The new expert systems do have the pp-

The head of intelligent systems at Xerox, John Seely Brown, the difference between dumb secretaries and smart ones who think fortikens the difference between expertcomputersystems andhuman expertsto themselves. He says his own secretary, Dana Bloomberg, is exceptional.

DHOTOGRAPH BY

CHUCK

O'REAR AUGUST 20, 1984 FORTUNE 105

TECHNOLOGY

Frederick Hayes-Roth,36, thechiefscientistat TeknowledgeInc., oneofthe mostactivecompaniesin expertsystems, says thegreatestcontribution from work inthisfield maybe toprovidebasic information aboutthe ways thatexpertsmakedecisions.Notsurprisingly, expertsthemselveshavea difficult timedescribing theirthoughtprocesses.

tential to raise productivity in an array of advice, just like the supersmartcomputer inindustries. But quite afew computer scien- the movie WarGames. Such developmentstists, including prominent artificial intelli- almostcertainly are years and years away,genceresearchers like Marvin Minsky of the This is not to say that thepresent technol-Massachusetts Institute of Technology and ogy won't find plenty of real-world applica-Roger Schank of Yale, think that enthusiasm tions. Arthur D. Little, the Cambridge re-for the present technologyis out of hand, search firm, predicts that corporations andThe blossoming of interest in the field and governmentwill be spending$1.25 billion an-the outpouring of investment dollars have nually on expert systems by 1990. But thecreated the impression that scientific break- main uses of the technologywill be modestthroughs have suddenly openedthe wayfor by comparisonwith some of theclaims for it.countless new applications for expert sys- Expert systems will serve to multiply theterns. Yet Minsky and Schank contend that value of real experts byputting some of theirtoday's systems are largely based on 20- knowledge at the fingertipsof nonexperts.Ayear-old programming techniques that have few systems are already performing credit-merelybecome practical as computer power ably at such tasks—helping to sell comput-got cheaper. Truly significant advances in ers, to repairmachines, orto makechemicalcomputer intelligence, they say, awaitfuture analyses, for instance—and showing prom-breakthroughs in programming. ise at other applications, such as teaching

Expert systems that canroutinely outper- systemsfor the military(see the photographform human experts will be much rarer than on page 108).the hoopla suggests. Only one such systemexists today,and ithasbeen around since the gW ESPITE THEIR ORIGINS in artifi-mid-19605. Yet proponents of expert sys- c^ intelligence research, expertterns envision scenarios in which, for exam- W^m systems have no morespecial claimpie, various medical specialists would pool to "intelligence"than manyconven-their expertise in a diagnostic system that tional computer programs. In

fact,

expertwould prove superior to anydoctor. Another systems display fewer of the attributes clas-promisedfantasy is an "information fusion" sically associated with intelligence, such assystem that will automatically gather, syn- the ability to learn or to discern patternsthesize, and analyze information from many amid confusion, than code-breakingand deci-sources and then offer up conclusions and sion-aiding programsthat first emerged dur-Research AssociateJohn Paul NewportJr. ing World War 11. Those older efforts never

achieved anything like the glamourof expertsystems because theywere shrouded in se-crecy or wore unexciting labels like "opera-tions research."

The main connection between expertsys-terns and intelligence is that most of thesystems employ programming techniquespioneered by researchers trying to developcomputer models of how the mind works.Theresearchers perfectedways to separateprograms into twoparts. One is the "knowl-edgebase," a looselystructured collection ofrules that sum up the expertise in a givenfield. The second part, the "inference en-gine," is a sequence of logic-like operationsthat manipulateand combine the rules in theknowledge base. The separation permitsprogrammers to revise the knowledge orsubstitute knowledge about an entirely dif-ferent subject without doingviolence to theprogram as a whole. Conventional program-ming techniques usually mixknowledge andinstructions together,making them about asamenable to casual modification as a Swisswatch.

Artificial intelligenceresearchers also in-ventedcomputer languagesthat can manipu-late strings of nonnumerical symbols—suchas English words and sentences—and emu-late the deductive operationsof classical log-ic. If told, for example,that (1) Socrates is aman and (2) all men are mortal, many expertsystems can infer that Socrates is mortal.

The controversy overthepotential of ex-pert systems centers on their conceptualsimplicity. The systems recognize patternsof symbols—such as "Who was Socrates?"—and match the words and sentences inthose patterns against others in the knowl-edgebase.But the computerworks mechani-cally, manipulatingarid symbols that itrecog-nizes but does not understand. It does notdeal in the rich associations, metaphors, andgeneralizationsthat language evokes in peo-ple and that constitute the essence of mean-ing and thought. Thinking consists less oflogic andrecognizing symbols than it does ofmental images and analogics—things no onehas been able to define in terms computerscan grasp. So while expert systems cansometimes display an amazingsemblance ofhuman expertise and logic, it is an emptymimicry, the limited repertoire of a clock-work doll rather than a respectable simula-tion of human intellect.

How far can such mechanical mimicry goin addressing really difficult problems? Forthe past 15 years the U.S. government haspoured millions of dollars into more than adozen efforts to automate medical diagnosis

106 FORTUNE AUGUST 20, 1984

Notes on Wine and Wine Appreciation

The Loire is the longest river in France,extending from the mountains in central France,known as MassifCentral, to the Atlantic more than600 miles away.

It ribbons its

way

past half a million acres ofvines tended by thousands of

growers,

coursing byOrleans, of Joan of Arc fame, and Tours, world-famous for spectacular chateaux. This mightywaterway is what links together an exceptionallywide variety ofwines.

Of the nine major districts, Muscadet, Anjou andTouraine are the largest and best known.

Unlike some other regions where wine isidentified by the producer's name, wines from theLoire tend to be characterized by the type of

grape

used and the village or region oforigin. CheninBlanc, Sauvignon Blanc and Muscadet are the threemajor

grapes

that produce the white for which theLoire is primarily known. Cabernet Franc andGamay are

grown

for the red and rose wines.Loire wines are versatile and interesting;

manycarry

the suggestion offruit flavor and aroma.Touraine, with its wine cellars in caves dug out of

chalk hills, gives us Vouvray, easily the most famousChenin Blanc with a unique crisp, apple-sweettaste.The Chenin Blanc

grape

is also called Pineaude la Loire.

Nearby Chinon and Bourgueil produce lighterbodied reds, perhaps the best in the Loire Valley.

Muscadet is the name ofthe

wine,

the area andthe

grape

itself. It is a lively and light

wine,

particularly appropriate with seafood fromneighboring Brittany.

The Upper Loire gives us Sancerre's 'flinty'wines which typify the Sauvignon Blanc

grape.

Pouilly-sur-Loire has a

very

attractive Pouilly Fume(not to be confused with Pouilly Fuisse ofsouthernBurgundy).

Anjou is famous for rose wines. Saumur, withinthe district, dependson the acidity ofChenin Blancfor its celebrated sparkling wines.

These notes are but an introduction to apicturesque region. Frederick Wildman suggeststhat

you

look for the J. Moreau

St

Fils andWildman labels for Vouvray, Muscadet andSancerre for summer sipping.

Copyright 1984, Frederick Wildman &. Sons,

Ltd.,

New

York,

NY

108 FORTUNE AUGUST 20, 1984

TECHNOLOGY

Aresearcheratßolt Beranek &Newman,a Cambridgecompany, shows offan expertsystem tohelptheNavytrainradaroperatorsonfighter-interceptors.The threescreensdisplayinformationabout enemyaircraft, missiles, and theplane'sactions, andrecordwhatthestudenthas toldthepilottodo. Aftera simulatedflight, thesystem tellsthestudentwhathedidrightand wrong.

and treatment. So far only two programs, a man perceptions of cause and effect. Solimited system called Puff that dealsin respi- while a diagnostic program can discourseratory diseases, and a program that inter- with apparent facility about symptoms andprets blood tests on a machine called Clini- diseases, it actually responds by rote withScan, are in regular clinical use. prerecordedknowledge that assumes more

The most ambitious medical project is a uniformity in the relationships betweensystem called Caduceus, which contains in- symptoms and diseases than actuallyexists,formation about some 700 diseases. Caduce- Physicians and other experts also use sur-us sometimes scores better thantop special- face knowledge when dealing with familiarists in its first guess at diagnosinga patient's cases. But when they get stuck, human ex-illness. But it's wrongoften enoughto make perts draw on their deepknowledgeto find ait impossible to rely on. One of Caduceus's solution. Pople is working on a second-gen-developers,Harry Pople of the Universityof eration Caduceus thathehopeswill somedayPittsburgh, says that the present system incorporate such abstract reasoning.won't be useful for anythingmore than help- Equipping programs with common senseing physicians organize their thoughts and is evenmore difficult than makingprogramsrule out implausiblediagnoses. that can reason deeply. John Seely Brown,

A major weakness of the medical pro- head ofXerox's intelligentsystemslaborato-grams is that they don't learn medicine the ry in Palo Alto, California, compares the dif-way doctors do—as a body of scientific prin- ference between current expertsystems andciples and causalrelations betweenphysical, true intelligenceto the differencebetween achemical, and biological entities. Instead, bad secretaryand a good one. "Every man-they are programmed with rules of thumb ager knows the difference," says Brown. "Arepresenting a physician's overt responses good secretary is one you simply tell whatto sets of symptoms: if the patient has a fe- you want done, andshe figures out how todover, a runny nose, and aches and pains, then it. A dumb one needs explicit instructionshe has flu. This "surface" knowledge, which abouteverything."A brilliant secretary,addsis easy to express in rules, is vastly different Brown, can handle emergencies when thefrom "deep"knowledge, or genuine under- boss is out of town,standingbased on scientific principles or hu- Brown's analogy offers a useful way to

-.

■

1

TECHNOLOGY

think about most existing expert systems: Unless programmers can anticipate all chanics. But they would be frustrating timewhat kinds of tasks would one entrust to a eventualities, the rule-bound expert system wasters if theproblemis, say, a potato in thetruly dumb, literal-minded,by-the-rules sec- could be even worse than any conceivably exhaust pipe. The term that artificial intelli-retary, even one possessingflawless memo- awful secretary: not knowing what it didn't gence people use for this shortcoming isry and endless patience? She might do a su- know, it would be bound to provide mislead- "brittleness," the tendencyto break ratherperb job, most of the time, of keeping out ing responses while having no idea it had thanbend gracefully or ask for help in thevisitors who arrive without appointments, done so. For example, several expert sys- presenceof the unusual.But she couldbe a menace in unusualcircum- terns can diagnoseautomobile breakdowns. Most people, in contrast, have the advan-stances—if, say, one of the Bass brothers They know all about ignition and fuel prob- tageof common sense. Theycan handle thecame callingwith an interesting deal. lems and mightbe terrific help to novice me- unusual bymakinganalogieswith their expe-

add new programs that

;

:'s probablybetter

__j_.j

testing devices.HumanEdgepacks its progr;

ality theories developed bybehavioral scientists using"human factor" analysis. Ac-cording to these theories,people fall into a relativelysmall number of personalitytypes. Human Edge's pro-grams supposedly tell a userhow to modify his behavior toachieve maximum leverageindealings with other personal-ity types.

A salesman might crank up ■Sales Edge to find out how tohandle a customer. First thesalesman answers questions ■about himself, stating wheth-er he agreesor disagreeswith .HBHuHSkstatements like the ones on Sales Edge asks 86 questions to assess its owner.

ybetter than anybody

__'__.

Til : ___.»_-__

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.aii oi tnis year, lac companypians 10 nsrsre advice on such matters as getting tioi

a-i-f owotofne _i__«*^

uic CAtciiLw wmui pcup.ic

cue OCU-SCI^UJ. C,

U/UglJ.-

-extroverted. Next the program creates a similar,

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Kiofl/I

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tlio dloomon'e trocs

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. cus-j

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tay be the questions, yuite a lew oi

bieuous ordeDendent on circumstances forYr\

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4axxT Allot..

ty cannavea considerable enect onme aavice tnedes. That said, it generally seemspossible to spotadvice and goback and find the ambiguousques-

aighs in with manyparagraphs about how tothe uncominc deal. It mieht say: "Your ten-

say.

xuui icu- ■:■■;;.;

2 ternative,it might suggest the* "narrative account" close:

since Jones craves an exhila-rating and successful life, hemight be swayed by tales ofother customerswho have ex-perienced exciting successwith theproduct. Or the pro-grammjght propose the "vicepresident close": callingsomebody higher up in thesalesman's company for Mr.Jonesto wrangle with. In grat-ifyinghis urgesfor powerandinfluence, that little touchmightbe justenoughto swaya tough customer like Jones.

112 FORTUNE AUGUST 20, 1984

tess is doing. Thepre;'s president, JamesI

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FORTUNE AUGUST 20, 19841 14

TECHNOLOGYriences, by extrapolating missing informa- mation orpoint out inconsistencies between faster and less error-prone than most DECtion, or by modifying imperfect instructions, their assumptions and established knowl- technicians. DEC says it has saved enoughThe trouble with tryingto programcommon edge. Martin Hollander, director of market- money using Xcon to have a "positive" re-sense—or even insights about potatoes and ing with IntelliCorp, a

$1.7-million-a-year

turn on its investment,exhaust pipes—into a computer is that it public company that sells software tools Hoping to achieve savings in a similarcould take literallymillions of idiosyncratic used to build expertsystems, sees a system fashion, major banks and insurance compa-nies. Most of those rules haven't been artic- functioning best as a "doubtingThomas" ad- nies are among the most enthusiastic back-datedwell enoughto convey to other human viser. "You give the system a hypothesis," ers of expertsystems development.Becausebeings, much less to computers, and there he says, "and the system runs through its their employeesmake judgments involvingare no signs that the limitation will be tran- rules and points out things it knows are in- large sums of money every day, managersscended anytime soon. consistent." As an example, Hollander sug- calculate that even minor improvements in

Beau Sheil, a manager of artificial intelli- gests that a systemfor designers of chemical those judgmentswould justify enormous re-gence systems with Xerox, observes: "It's plants might serve as akind of automateden- search outlays,extremelydifficult to clone experts except in gineering handbook, pointing out things that Peter Hart, president of Syntelligence, avery, very narrow, highly specified domains, an engineer shouldn't forget when scaling up privatelyowned expert systems company inYou can capture a lotof the surface behavior a pilotprocess to a commercial-size plant. Silicon Valley, is working with several finan-of an expert with rules, but what youreally cial institutions to build systems that would,get out of having an experthas a great deal Qk UT EXPERT SYSTEMS to help for example, incorporate therules of thumbmore depth and sophistication than rules W with even suchroutine tasks are ar- used by a bank's top loan or trust officers;would provide. A limit of expert systems is I slowly. One of thebestknown the systems couldbe usedby juniorofficersthat if the rules are wrong or don't apply in I ___P in use now is a four-year-old pro- inbranches. Hart seessuch software primar-this case, who tells? One thing that's sure is gram called Xcon that Digital Equipment ily as looking over the shoulders of lower-that the expert system doesn't tell." Corp. developedto ensure that its techni- level employees to ensure that they don't

Sheil concludes, as others have, that the cians select theright componentsfor custom make some of the mistakes that go with inex-main applications of expert systems will computer installations. Xcon can't dothe job perience.But he acknowledgesthat comput-probablybe to helpspecialistsmanage infor- better than the best DEC engineers, but it's ers won't helpwith some of the most impor-

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AUGUST 20, 1984 FORTUNE 1 15

tant decisions, such as those involving tions, putsforeignexchangepredictionin the and Vestal suspects it will be a long time be-judgmentsabout character drawnfrom per- category of things theprograms will proba- fore the system can replace a Gilreath.~onal encounters. bly notbe much good at (even if the experts Stories of expert systems smarter than

Anyone building expert systems has to themselves reallyare good). thebest geologists shouldberegarded skep-". 'rapple; with the reality that much of an ex- The oil industry is another big spenderon tically. One oft-told tale has it that Prospec-:.ert's knowledge is intuitive, or at least not expert systems. One ambitious effort is 'Dip- tor, a geology program developed by aeasily formulated into rules. SecurityPacific meter Advisor, a system developed by nonprofit California company called SRI In-national Bank in Los Angelesis working on a Schlumberger and now undergoing field tri- ternational, zeroed in on a molybdenum de-rogramto predictforeign exchangerates as als. The program interprets readings from posit in eastern Washington that geologists

\ service to large customers.It is drawing on instruments deepin the drill hole, called dip- had been unsuccessfully hunting since thehe knowledge of its foreign exchange trad- meters, that indicate the type of geological 19205. In fact, the initial discovery of molyb-rs, on the bold assumption that they can structure. Schlumberger sells advice about denum was made by humans, though Pros-uccessfully predict changes in rates. The exploratorywells that helps owners decide pector later found more ore. Its developers.ank has found that some factors that go into whether to keep going or write an operation merely claim that Prospector should be al-Tedictions by its foreign currency special- off as a dry hole.

,sts are quantitative and relatively easy tomostas goodat prospecting as geologistVic-tor Hollister, whose expertise was fed into

educe torules. But the forecasts are also in- Bk IPMETER ADVISOR represents the program.iuencedbymoresubjective variables—com- somewhere between eight and 20 Frederick Hayes-Roth, the chief scientist.ion sense, anecdotal evidence, confidence man-years of labor by several pro- at Teknowledge Inc., a three-year-old pri-evels—that are difficult to articulate. grammers trying to clone the vate company in Palo Alto, says the proper

Joseph Heinen, Security Pacific's vice knowledge of a single expert, Al Gilreath, a applications for expert systems are what hepresident in charge of advanced technology specialist on geological formations off the calls structured selection problems. Thesefor data processing,hopes thebankwill have Gulf Coast. Stanley Vestal, software coordi- are situations involving a limited number ofi limited currency prediction system avail- nator at Schlumberger's engineeringcenter choices arrived at by weighing judgmentsable for customers before the year is out. inAustin, Texas,estimates that the program about complicated alternatives, such asBut another player in the field, Kenneth P. can interpret Gulf-area dipmeter readings as scheduling factory operations or designingMorse of Applied Expert Systems in Cam- well as a junior geologistabout 90% of the insurance policies. "If a technically trainedbridge, a private company developingexpert time. On the other 10%, however, Gilreath person who's narrowly specializedcan givesystems for several financial service institu- or another senior geologist has to step in, useful advice, then an expert system is

1 16 FORTUNE AUGUST 20, 1984

TECHNOLOGY

ijlfjurely you're not£>oin£ to fly so

far away from homejust to stay in anordinary hotel.

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New York(The Pierre)Chicago (The Ritz-Carlton)

Dallas " HoustonPhiladelphia " San Antonio

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Edmonton " VancouverInn on the Park

Houston " London " TorontoCall your Travel Agent

Schlumberger is developinganexpertsystemcalledDipmeterAdvisorto analyzedatacollecteddeepin oilandgaswells. Al

Gilreath,

59, thegeologistwhoseknowledge wasusedto build thesystem,compares aprintoutofdatagatheredatawell site with thesystem 's inferences about surroundinggeologicalstructures. Thesystem isas accurateas juniorgeologists90%ofthe time.

likely to prove quite good," says Hayes- impossible topredict. Highprices and unceiRoth. tainty about performance make expert sys

Thekinds of applications for which expert terns a hard sell. Companies in the businessystems are likelyto improve on human ex- have devised an assortment of strategies tperts are very specialized and very few. make theirtechnologiesattractive.A CaliforAmong them are situations that are toofast- nia start-up, Human Edge Software, is winmoving and stressful to be left to people, ning customers with low-price systems deThemost obvious example,and the object of signed for use on personal computers (se<research byseveral companies, is thecontrol box). Another private company, Smart Sysof nuclear powerplants during emergencies, terns TechnologyinVirginia,has made a spe

The lone existingexpert system that rou- cialtyof teaching knowledge engineering tcfinely beatshuman expertsis Dendral, devel- its customers' programmers, while Brattkoped at Stanford 20 years ago. The latest Research of Cambridgeand others build cusversion of Dendral is Genoa, a system sold tom-tailored systems for clients. Some comby Molecular Design Limited, a private com- panicshave developedsystems in-house thatpany in Hayward, California. When fed par- may have a broader market. For exampletial analyses by chemists, Genoa can deter- General Electric has developed a prograirmine the structure of unknown compounds, that itwill market to helprailroad mechanicssuch as pollutants.The system is moreprofi- diagnose and repair GE locomotives in thecient than human experts only because the field, without having to drag them to centralprocess of comparing chemical substances repair yards.with every conceivable molecular structure Other vendors and would-be users pinthat might contain them involves so many their hopes on the recent emergence of ancomputations that no chemist could perform industry in expert system "shells." Thesean exhaustive analysis. are off-the-shelf inference engines that users

can equip with special expertise for doing

CREATING a new expert system can anything from analyzing the source ofpollut-take many man-years of work by ants in streams to selecting the right dinnerscarce specialists called knowledge wine. Taylor Instrument of Rochester, Newengineers—part programmers, part York, a division of Combustion Engineering,

psychologists—and can eat up $1 million or uses shells from several suppliers to buildmore. Worse, the costs and the chances for systemsfor controllingprocessing plants,success of a pioneering project are almost Major shell vendors include Teknowledge,

1

I

financefor industry

The Participants' meeting of Istituto Mobiliare Italiano approved theFinancial Statements as ofMarch 31, 1984.TheFinancial Statements we-re audited by Arthur Loans outstanding 21,476 billion LireAndersen and Co.s.a.s. Net income 142 billion Lire

ISTITUTO MOBILIARE ITALIANO - Public Law Credit InstitutionHead Office in Rome(Italy) - Subsidiaries abroad and representative

Offices in: Brussels,

Frankfurt-on-Main,

Jersey (Channel Islands),London, Luxembourg, Mexico City, Rotterdam, Zurich, Washington

RegionalOffices in Italy:Milan, Turin,

Genoa,

Padua, Venice, Bologna, Florence, Rome,Naples,Bari, Catania.

TECHNOLOGYIntelliCorp, a Virginia company called Soft-ware Architecture & Engineering, and SPLInternational, a British company. Sales ofshells, which cost up to $60,000, are slow,and only one vendor has sold more than 60.Several companies have begun to lower thespecs and prices of their software.

In number of units sold, the most success-ful shell vendor is Expert Software Interna-tional Ltd., a Scottish company. ExpertSoftware has sold about 150 copies of a$2,000 program called Expert-Ease. Thecompany claims that Expert-Ease, whichruns on computers as small as the IBM PC,can be used to design systems that can su-pervise repairs of factory machinery, trainnew employees, and formulate decisionrulesfor low-level employees.

Expert-Ease and a $40,000 system calledTIMM (for The IntelligentMachine Model),produced by a subsidiary of Flow General(1983 sales: $129 million), differ from main-stream expert systems by relying on induc-tiverather than deductiveprinciples. Where-as a deductive system works by goingstep-by-step through all the preprogrammedrules, an inductive inference enginelooks forthe variables that affect the outcomein a sit-uation and throws out the ones that don'tmatter. Applied to the task of spottingfaultsonelectronic circuit boards, Expert-Easefig-ured out that only three tests were neces-saryinstead of the 20 that human technicianshad been using.

lem solving, including Roger L. Barron, aconsultant to Flow General, argue that mostresearch on expert systems is too narrowlyfocused on the symbol-oriented logic of arti-ficial intelligence.They contend that marry-ing this approach with powerful mathemati-cal and statistical techniques might lead toexpert systems that reallycould solve prob-lems beyond the capacityof the human brain.

Another challenge will be to make expertsystems cost effective. A recent market sur-vey by Gartner Group, a Connecticut re-search firm, found plenty of interest in sys-tems that could handle tasks such asrationalizing factory schedules, processinginsurance claims, and even supplying invest-ment advice. But the study concluded thatmost of today'sexpertsystemsare limited inapplication,narrow in scope, and quitecostly.Gartner Group believes that most makersand users of expert systems are still yearsaway from getting substantial returns ontheir investments. Bothwould do well to dis-count the hoopla and put their ownexpertiseto workcalculating costs and benefits. □

Loans outstanding 21,476 billion Lire

118 FORTUNE AUGUST 20, 1984

v uctu usmg.

Some authorities on computer-aidedprob-