下载辰思小说免费APP
Whenspeakingofuninvitingobjects,Imeanthosewhichdonotpassfromonesensationtotheopposite;invitingobjectsarethosewhichdo;inthislattercasethesensecomingupontheobject,whetheratadistanceornear,givesnomorevividideaofanythinginparticularthanofitsopposite。Anillustrationwillmakemymeaningclearer:——herearethreefingers——alittlefinger,asecondfinger,andamiddlefinger。
Verygood。
Youmaysupposethattheyareseenquiteclose:Andherecomesthepoint。
Whatisit?
Eachofthemequallyappearsafinger,whetherseeninthemiddleorattheextremity,whetherwhiteorblack,orthickorthin——itmakesnodifference;afingerisafingerallthesame。Inthesecasesamanisnotcompelledtoaskofthoughtthequestion,whatisafinger?forthesightneverintimatestothemindthatafingerisotherthanafinger。
True。
Andtherefore,Isaid,aswemightexpect,thereisnothingherewhichinvitesorexcitesintelligence。
Thereisnot,hesaid。
Butisthisequallytrueofthegreatnessandsmallnessofthefingers?Cansightadequatelyperceivethem?andisnodifferencemadebythecircumstancethatoneofthefingersisinthemiddleandanotherattheextremity?Andinlikemannerdoesthetouchadequatelyperceivethequalitiesofthicknessorthinness,orsoftnessorhardness?Andsooftheothersenses;dotheygiveperfectintimationsofsuchmatters?Isnottheirmodeofoperationonthiswise——thesensewhichisconcernedwiththequalityofhardnessisnecessarilyconcernedalsowiththequalityofsoftness,andonlyintimatestothesoulthatthesamethingisfelttobebothhardandsoft?
Youarequiteright,hesaid。
Andmustnotthesoulbeperplexedatthisintimationwhichthesensegivesofahardwhichisalsosoft?What,again,isthemeaningoflightandheavy,ifthatwhichislightisalsoheavy,andthatwhichisheavy,light?
Yes,hesaid,theseintimationswhichthesoulreceivesareverycuriousandrequiretobeexplained。
Yes,Isaid,andintheseperplexitiesthesoulnaturallysummonstoheraidcalculationandintelligence,thatshemayseewhethertheseveralobjectsannouncedtoherareoneortwo。
True。
Andiftheyturnouttobetwo,isnoteachofthemoneanddifferent?
Certainly。
Andifeachisone,andbotharetwo,shewillconceivethetwoasinastateofdivision,foriftherewereundividedtheycouldonlybeconceivedofasone?
True。
Theeyecertainlydidseebothsmallandgreat,butonlyinaconfusedmanner;theywerenotdistinguished。
Yes。
Whereasthethinkingmind,intendingtolightupthechaos,wascompelledtoreversetheprocess,andlookatsmallandgreatasseparateandnotconfused。
Verytrue。
Wasnotthisthebeginningoftheenquiry’Whatisgreat?’and’Whatissmall?’
Exactlyso。
Andthusarosethedistinctionofthevisibleandtheintelligible。
Mosttrue。
ThiswaswhatImeantwhenIspokeofimpressionswhichinvitedtheintellect,orthereverse——thosewhicharesimultaneouswithoppositeimpressions,invitethought;thosewhicharenotsimultaneousdonot。
Iunderstand,hesaid,andagreewithyou。
Andtowhichclassdounityandnumberbelong?
Idonotknow,hereplied。
Thinkalittleandyouwillseethatwhathasprecededwillsupplytheanswer;forifsimpleunitycouldbeadequatelyperceivedbythesightorbyanyothersense,then,asweweresayinginthecaseofthefinger,therewouldbenothingtoattracttowardsbeing;butwhenthereissomecontradictionalwayspresent,andoneisthereverseofoneandinvolvestheconceptionofplurality,thenthoughtbeginstobearousedwithinus,andthesoulperplexedandwantingtoarriveatadecisionasks’Whatisabsoluteunity?’Thisisthewayinwhichthestudyoftheonehasapowerofdrawingandconvertingthemindtothecontemplationoftruebeing。
Andsurely,hesaid,thisoccursnotablyinthecaseofone;forweseethesamethingtobebothoneandinfiniteinmultitude?
Yes,Isaid;andthisbeingtrueofonemustbeequallytrueofallnumber?
Certainly。
Andallarithmeticandcalculationhavetodowithnumber?
Yes。
Andtheyappeartoleadthemindtowardstruth?
Yes,inaveryremarkablemanner。
Thenthisisknowledgeofthekindforwhichweareseeking,havingadoubleuse,militaryandphilosophical;forthemanofwarmustlearntheartofnumberorhewillnotknowhowtoarrayhistroops,andthephilosopheralso,becausehehastoriseoutoftheseaofchangeandlayholdoftruebeing,andthereforehemustbeanarithmetician。
Thatistrue。
Andourguardianisbothwarriorandphilosopher?
Certainly。
Thenthisisakindofknowledgewhichlegislationmayfitlyprescribe;andwemustendeavourtopersuadethosewhoareprescribetobetheprincipalmenofourStatetogoandlearnarithmetic,notasamateurs,buttheymustcarryonthestudyuntiltheyseethenatureofnumberswiththemindonly;noragain,likemerchantsorretail—traders,withaviewtobuyingorselling,butforthesakeoftheirmilitaryuse,andofthesoulherself;andbecausethiswillbetheeasiestwayforhertopassfrombecomingtotruthandbeing。
Thatisexcellent,hesaid。
Yes,Isaid,andnowhavingspokenofit,Imustaddhowcharmingthescienceis!andinhowmanywaysitconducestoourdesiredend,ifpursuedinthespiritofaphilosopher,andnotofashopkeeper!
Howdoyoumean?
Imean,asIwassaying,thatarithmetichasaverygreatandelevatingeffect,compellingthesoultoreasonaboutabstractnumber,andrebellingagainsttheintroductionofvisibleortangibleobjectsintotheargument。Youknowhowsteadilythemastersoftheartrepelandridiculeanyonewhoattemptstodivideabsoluteunitywhenheiscalculating,andifyoudivide,theymultiply,takingcarethatoneshallcontinueoneandnotbecomelostinfractions。
Thatisverytrue。
Now,supposeapersonweretosaytothem:Omyfriends,whatarethesewonderfulnumbersaboutwhichyouarereasoning,inwhich,asyousay,thereisaunitysuchasyoudemand,andeachunitisequal,invariable,indivisible,——whatwouldtheyanswer?
Theywouldanswer,asIshouldconceive,thattheywerespeakingofthosenumberswhichcanonlyberealisedinthought。
Thenyouseethatthisknowledgemaybetrulycallednecessary,necessitatingasitclearlydoestheuseofthepureintelligenceintheattainmentofpuretruth?
Yes;thatisamarkedcharacteristicofit。
Andhaveyoufurtherobserved,thatthosewhohaveanaturaltalentforcalculationaregenerallyquickateveryotherkindofknowledge;andeventhedulliftheyhavehadanarithmeticaltraining,althoughtheymayderivenootheradvantagefromit,alwaysbecomemuchquickerthantheywouldotherwisehavebeen。
Verytrue,hesaid。
Andindeed,youwillnoteasilyfindamoredifficultstudy,andnotmanyasdifficult。
Youwillnot。
And,forallthesereasons,arithmeticisakindofknowledgeinwhichthebestnaturesshouldbetrained,andwhichmustnotbegivenup。
Iagree。
Letthisthenbemadeoneofoursubjectsofeducation。Andnext,shallweenquirewhetherthekindredsciencealsoconcernsus?
Youmeangeometry?
Exactlyso。
Clearly,hesaid,weareconcernedwiththatpartofgeometrywhichrelatestowar;forinpitchingacamp,ortakingupaposition,orclosingorextendingthelinesofanarmy,oranyothermilitarymanoeuvre,whetherinactualbattleoronamarch,itwillmakeal