六级阅读理解CantheComputerLearnfromExperience计算机会总结经验吗Computershavebeentaughttoplaynotonlycheckers,butalsochampionshipchess,whichisafairlyaccurateyardstickformeasuringthecomputer’sprogressintheabilitytolearnfromexperience.Becausethegamerequireslogicalreasoning,chesswouldseemtobeperfectlysuitedtothecomputer.allaprogrammerhastodoisgivethecomputeraprogramevaluatingtheconsequencesofeverypossibleresponsetoeverypossiblemove,andthecomputerwillwineverytime.Intheorythisisasensibleapproach;inpracticeitisimpossible.Today,apowerfulcomputercananalyze40000movesasecond.Thatisanimpressivespeed.Butthereareanastronomicalnumberofpossiblemovesinchess—literallytrillions.Evenifsuchaprogramwerewritten(andintheoryitcouldbe,givenenoughpeopleandenoughtime),thereisnocomputercapableofholdingthatmuchdata.Therefore,ifthecomputeristocompeteatchampionshiplevels,itmustbeprogrammedtofunctionwithlessthancompletedata.Itmustbeabletolearnfromexperience,tomodifyitsownprogramm,todealwitharelativelyunstructuredsituation—inaword,to“think”foritself.Infact,thiscanbedone.Chess-playingcomputershaveyettodefeatworldchampionchessplayers,butseveralhavebeatenhumanplayersofonlyslightlylowerranks.Thecomputershavehadprogramstocarrythemthroughtheearly,mechanicalstagesoftheirchessgames.Buttheyhavegoneonfromtheretoreasonandlearn,andsometimestowinthegame.Thereareotherproofsthatcomputerscanbeprogrammedtolearn,butthisexampleissufficienttodemonstratethepoint.Granted,winningagameofchessisnotanearthshakingeventevenwhenacomputerdoesit.Buttherearemanyserioushumanproblemswhichbanbefruitfullyapproachedasgames.TheDefenseDepartmentusescomputerstoplaywargamesandworkoutstrategiesfordealingwithinternationaltensions.Otherproblems—internationalandinterpersonalrelations,ecologyandeconomics,andtheever-increasingthreatofworldfamine—canperhapsbesolvedbythejointeffortsofhumanbeingsandtrulyintelligentcomputers.Notescheck:agameplayedonacheckerboardbytwoplayers,eachusing12piecesecology:therelationshipbetweenorganismsandtheirenv...
