CATEGORIES

第1章

Thingsaresaidtobenamed"equivocally"when，thoughtheyhaveacommonname，thedefinitioncorrespondingwiththenamediffersforeach。Thus，arealmanandafigureinapicturecanbothlayclaimtothename"animal"；yettheseareequivocallysonamed，for，thoughtheyhaveacommonname，thedefinitioncorrespondingwiththenamediffersforeach。Forshouldanyonedefineinwhatsenseeachisananimal，hisdefinitionintheonecasewillbeappropriatetothatcaseonly。

Ontheotherhand，thingsaresaidtobenamed"univocally"whichhaveboththenameandthedefinitionansweringtothenameincommon。

Amanandanoxareboth"animal"，andtheseareunivocallysonamed，inasmuchasnotonlythename，butalsothedefinition，isthesameinbothcases：forifamanshouldstateinwhatsenseeachisananimal，thestatementintheonecasewouldbeidenticalwiththatintheother。

Thingsaresaidtobenamed"derivatively"，whichderivetheirnamefromsomeothername，butdifferfromitintermination。Thusthegrammarianderiveshisnamefromtheword"grammar"，andthecourageousmanfromtheword"courage"。

Formsofspeechareeithersimpleorcomposite。Examplesofthelatteraresuchexpressionsas"themanruns"，"themanwins"；oftheformer"man"，"ox"，"runs"，"wins"。

Ofthingsthemselvessomearepredicableofasubject，andareneverpresentinasubject。Thus"man"ispredicableoftheindividualman，andisneverpresentinasubject。

Bybeing"presentinasubject"Idonotmeanpresentaspartsarepresentinawhole，butbeingincapableofexistenceapartfromthesaidsubject。

Somethings，again，arepresentinasubject，butareneverpredicableofasubject。Forinstance，acertainpointofgrammaticalknowledgeispresentinthemind，butisnotpredicableofanysubject；oragain，acertainwhitenessmaybepresentinthebody（forcolourrequiresamaterialbasis），yetitisneverpredicableofanything。

Otherthings，again，arebothpredicableofasubjectandpresentinasubject。Thuswhileknowledgeispresentinthehumanmind，itispredicableofgrammar。

Thereis，lastly，aclassofthingswhichareneitherpresentinasubjectnorpredicableofasubject，suchastheindividualmanortheindividualhorse。But，tospeakmoregenerally，thatwhichisindividualandhasthecharacterofaunitisneverpredicableofasubject。Yetinsomecasesthereisnothingtopreventsuchbeingpresentinasubject。Thusacertainpointofgrammaticalknowledgeispresentinasubject。

Whenonethingispredicatedofanother，allthatwhichispredicableofthepredicatewillbepredicablealsoofthesubject。

Thus，"man"ispredicatedoftheindividualman；but"animal"ispredicatedof"man"；itwill，therefore，bepredicableoftheindividualmanalso：fortheindividualmanisboth"man"and"animal"。

Ifgeneraaredifferentandco-ordinate，theirdifferentiaearethemselvesdifferentinkind。Takeasaninstancethegenus"animal"

andthegenus"knowledge"。"Withfeet"，"two-footed"，"winged"，"aquatic"，aredifferentiaeof"animal"；thespeciesofknowledgearenotdistinguishedbythesamedifferentiae。Onespeciesofknowledgedoesnotdifferfromanotherinbeing"two-footed"。

Butwhereonegenusissubordinatetoanother，thereisnothingtopreventtheirhavingthesamedifferentiae：forthegreaterclassispredicatedofthelesser，sothatallthedifferentiaeofthepredicatewillbedifferentiaealsoofthesubject。

Expressionswhichareinnowaycompositesignifysubstance，quantity，quality，relation，place，time，position，state，action，oraffection。Tosketchmymeaningroughly，examplesofsubstanceare"man"or"thehorse"，ofquantity，suchtermsas"twocubitslong"

or"threecubitslong"，ofquality，suchattributesas"white"，"grammatical"。"Double"，"half"，"greater"，fallunderthecategoryofrelation；"inamarketplace"，"intheLyceum"，underthatofplace；"yesterday"，"lastyear"，underthatoftime。"Lying"，"sitting"，aretermsindicatingposition，"shod"，"armed"，state；

"tolance"，"tocauterize"，action；"tobelanced"，"tobecauterized"，affection。

Nooneoftheseterms，inandbyitself，involvesanaffirmation；itisbythecombinationofsuchtermsthatpositiveornegativestatementsarise。Foreveryassertionmust，asisadmitted，beeithertrueorfalse，whereasexpressionswhicharenotinanywaycompositesuchas"man"，"white"，"runs"，"wins"，cannotbeeithertrueorfalse。

Substance，inthetruestandprimaryandmostdefinitesenseoftheword，isthatwhichisneitherpredicableofasubjectnorpresentinasubject；forinstance，theindividualmanorhorse。Butinasecondarysensethosethingsarecalledsubstanceswithinwhich，asspecies，theprimarysubstancesareincluded；alsothosewhich，asgenera，includethespecies。Forinstance，theindividualmanisincludedinthespecies"man"，andthegenustowhichthespeciesbelongsis"animal"；these，therefore-thatistosay，thespecies"man"andthegenus"animal，-aretermedsecondarysubstances。

Itisplainfromwhathasbeensaidthatboththenameandthedefinitionofthepredicatemustbepredicableofthesubject。Forinstance，"man"ispredictedoftheindividualman。Nowinthiscasethenameofthespeciesman"isappliedtotheindividual，forweusetheterm"man"indescribingtheindividual；andthedefinitionof"man"willalsobepredicatedoftheindividualman，fortheindividualmanisbothmanandanimal。Thus，boththenameandthedefinitionofthespeciesarepredicableoftheindividual。

Withregard，ontheotherhand，tothosethingswhicharepresentinasubject，itisgenerallythecasethatneithertheirnamenortheirdefinitionispredicableofthatinwhichtheyarepresent。

Though，however，thedefinitionisneverpredicable，thereisnothingincertaincasestopreventthenamebeingused。Forinstance，"white"beingpresentinabodyispredicatedofthatinwhichitispresent，forabodyiscalledwhite：thedefinition，however，ofthecolourwhite"isneverpredicableofthebody。

Everythingexceptprimarysubstancesiseitherpredicableofaprimarysubstanceorpresentinaprimarysubstance。Thisbecomesevidentbyreferencetoparticularinstanceswhichoccur。"Animal"

ispredicatedofthespecies"man"，thereforeoftheindividualman，foriftherewerenoindividualmanofwhomitcouldbepredicated，itcouldnotbepredicatedofthespecies"man"atall。Again，colourispresentinbody，thereforeinindividualbodies，foriftherewerenoindividualbodyinwhichitwaspresent，itcouldnotbepresentinbodyatall。Thuseverythingexceptprimarysubstancesiseitherpredicatedofprimarysubstances，orispresentinthem，andiftheselastdidnotexist，itwouldbeimpossibleforanythingelsetoexist。

Ofsecondarysubstances，thespeciesismoretrulysubstancethanthegenus，beingmorenearlyrelatedtoprimarysubstance。Forifanyoneshouldrenderanaccountofwhataprimarysubstanceis，hewouldrenderamoreinstructiveaccount，andonemorepropertothesubject，bystatingthespeciesthanbystatingthegenus。Thus，hewouldgiveamoreinstructiveaccountofanindividualmanbystatingthathewasmanthanbystatingthathewasanimal，fortheformerdescriptionispeculiartotheindividualinagreaterdegree，whilethelatteristoogeneral。Again，themanwhogivesanaccountofthenatureofanindividualtreewillgiveamoreinstructiveaccountbymentioningthespecies"tree"thanbymentioningthegenus"plant"。

Moreover，primarysubstancesaremostproperlycalledsubstancesinvirtueofthefactthattheyaretheentitieswhichunderlieevery。

else，andthateverythingelseiseitherpredicatedofthemorpresentinthem。Nowthesamerelationwhichsubsistsbetweenprimarysubstanceandeverythingelsesubsistsalsobetweenthespeciesandthegenus：forthespeciesistothegenusassubjectistopredicate，sincethegenusispredicatedofthespecies，whereasthespeciescannotbepredicatedofthegenus。Thuswehaveasecondgroundforassertingthatthespeciesismoretrulysubstancethanthegenus。

Ofspeciesthemselves，exceptinthecaseofsuchasaregenera，nooneismoretrulysubstancethananother。Weshouldnotgiveamoreappropriateaccountoftheindividualmanbystatingthespeciestowhichhebelonged，thanweshouldofanindividualhorsebyadoptingthesamemethodofdefinition。Inthesameway，ofprimarysubstances，nooneismoretrulysubstancethananother；anindividualmanisnotmoretrulysubstancethananindividualox。

Itis，then，withgoodreasonthatofallthatremains，whenweexcludeprimarysubstances，weconcedetospeciesandgeneraalonethename"secondarysubstance"，forthesealoneofallthepredicatesconveyaknowledgeofprimarysubstance。Foritisbystatingthespeciesorthegenusthatweappropriatelydefineanyindividualman；andweshallmakeourdefinitionmoreexactbystatingtheformerthanbystatingthelatter。Allotherthingsthatwestate，suchasthatheiswhite，thatheruns，andsoon，areirrelevanttothedefinition。Thusitisjustthatthesealone，apartfromprimarysubstances，shouldbecalledsubstances。

Further，primarysubstancesaremostproperlysocalled，becausetheyunderlieandarethesubjectsofeverythingelse。Nowthesamerelationthatsubsistsbetweenprimarysubstanceandeverythingelsesubsistsalsobetweenthespeciesandthegenustowhichtheprimarysubstancebelongs，ontheonehand，andeveryattributewhichisnotincludedwithinthese，ontheother。Forthesearethesubjectsofallsuch。Ifwecallanindividualman"skilledingrammar"，thepredicateisapplicablealsotothespeciesandtothegenustowhichhebelongs。Thislawholdsgoodinallcases。

Itisacommoncharacteristicofallsub。stancethatitisneverpresentinasubject。Forprimarysubstanceisneitherpresentinasubjectnorpredicatedofasubject；while，withregardtosecondarysubstances，itisclearfromthefollowingarguments（apartfromothers）thattheyarenotpresentinasubject。For"man"ispredicatedoftheindividualman，butisnotpresentinanysubject：

formanhoodisnotpresentintheindividualman。Inthesameway，"animal"isalsopredicatedoftheindividualman，butisnotpresentinhim。Again，whenathingispresentinasubject，thoughthenamemayquitewellbeappliedtothatinwhichitispresent，thedefinitioncannotbeapplied。Yetofsecondarysubstances，notonlythename，butalsothedefinition，appliestothesubject：weshoulduseboththedefinitionofthespeciesandthatofthegenuswithreferencetotheindividualman。Thussubstancecannotbepresentinasubject。

Yetthisisnotpeculiartosubstance，foritisalsothecasethatdifferentiaecannotbepresentinsubjects。Thecharacteristics"terrestrial"and"two-footed"arepredicatedofthespecies"man"，butnotpresentinit。Fortheyarenotinman。Moreover，thedefinitionofthedifferentiamaybepredicatedofthatofwhichthedifferentiaitselfispredicated。Forinstance，ifthecharacteristic"terrestrial"ispredicatedofthespecies"man"，thedefinitionalsoofthatcharacteristicmaybeusedtoformthepredicateofthespecies"man"：for"man"isterrestrial。

Thefactthatthepartsofsubstancesappeartobepresentinthewhole，asinasubject，shouldnotmakeusapprehensivelestweshouldhavetoadmitthatsuchpartsarenotsubstances：forinexplainingthephrase"beingpresentinasubject"，westated"thatwemeant"otherwisethanaspartsinawhole"。

Itisthemarkofsubstancesandofdifferentiaethat，inallpropositionsofwhichtheyformthepredicate，theyarepredicatedunivocally。Forallsuchpropositionshavefortheirsubjecteithertheindividualorthespecies。Itistruethat，inasmuchasprimarysubstanceisnotpredicableofanything，itcanneverformthepredicateofanyproposition。Butofsecondarysubstances，thespeciesispredicatedoftheindividual，thegenusbothofthespeciesandoftheindividual。Similarlythedifferentiaearepredicatedofthespeciesandoftheindividuals。Moreover，thedefinitionofthespeciesandthatofthegenusareapplicabletotheprimarysubstance，andthatofthegenustothespecies。Forallthatispredicatedofthepredicatewillbepredicatedalsoofthesubject。Similarly，thedefinitionofthedifferentiaewillbeapplicabletothespeciesandtotheindividuals。Butitwasstatedabovethattheword"univocal"

wasappliedtothosethingswhichhadbothnameanddefinitionincommon。Itis，therefore，establishedthatineveryproposition，ofwhicheithersubstanceoradifferentiaformsthepredicate，thesearepredicatedunivocally。

Allsubstanceappearstosignifythatwhichisindividual。Inthecaseofprimarysubstancethisisindisputablytrue，forthethingisaunit。Inthecaseofsecondarysubstances，whenwespeak，forinstance，of"man"or"animal"，ourformofspeechgivestheimpressionthatweareherealsoindicatingthatwhichisindividual，buttheimpressionisnotstrictlytrue；forasecondarysubstanceisnotanindividual，butaclasswithacertainqualification；foritisnotoneandsingleasaprimarysubstanceis；

thewords"man"，"animal"，arepredicableofmorethanonesubject。

Yetspeciesandgenusdonotmerelyindicatequality，liketheterm"white"；"white"indicatesqualityandnothingfurther，butspeciesandgenusdeterminethequalitywithreferencetoasubstance：

theysignifysubstancequalitativelydifferentiated。Thedeterminatequalificationcoversalargerfieldinthecaseofthegenusthatinthatofthespecies：hewhousestheword"animal"ishereinusingawordofwiderextensionthanhewhousestheword"man"。

Anothermarkofsubstanceisthatithasnocontrary。Whatcouldbethecontraryofanyprimarysubstance，suchastheindividualmanoranimal？Ithasnone。Norcanthespeciesorthegenushaveacontrary。Yetthischaracteristicisnotpeculiartosubstance，butistrueofmanyotherthings，suchasquantity。Thereisnothingthatformsthecontraryof"twocubitslong"orof"threecubitslong"，orof"ten"，orofanysuchterm。Amanmaycontendthat"much"isthecontraryof"little"，or"great"of"small"，butofdefinitequantitativetermsnocontraryexists。

Substance，again，doesnotappeartoadmitofvariationofdegree。I

donotmeanbythisthatonesubstancecannotbemoreorlesstrulysubstancethananother，forithasalreadybeenstated"thatthisisthecase；butthatnosinglesubstanceadmitsofvaryingdegreeswithinitself。Forinstance，oneparticularsubstance，"man"，cannotbemoreorlessmaneitherthanhimselfatsomeothertimeorthansomeotherman。Onemancannotbemoremanthananother，asthatwhichiswhitemaybemoreorlesswhitethansomeotherwhiteobject，orasthatwhichisbeautifulmaybemoreorlessbeautifulthansomeotherbeautifulobject。Thesamequality，moreover，issaidtosubsistinathinginvaryingdegreesatdifferenttimes。Abody，beingwhite，issaidtobewhiteratonetimethanitwasbefore，or，beingwarm，issaidtobewarmerorlesswarmthanatsomeothertime。Butsubstanceisnotsaidtobemoreorlessthatwhichitis：amanisnotmoretrulyamanatonetimethanhewasbefore，norisanything，ifitissubstance，moreorlesswhatitis。Substance，then，doesnotadmitofvariationofdegree。

Themostdistinctivemarkofsubstanceappearstobethat，whileremainingnumericallyoneandthesame，itiscapableofadmittingcontraryqualities。Fromamongthingsotherthansubstance，weshouldfindourselvesunabletobringforwardanywhichpossessedthismark。Thus，oneandthesamecolourcannotbewhiteandblack。Norcanthesameoneactionbegoodandbad：thislawholdsgoodwitheverythingthatisnotsubstance。Butoneandtheselfsamesubstance，whileretainingitsidentity，isyetcapableofadmittingcontraryqualities。Thesameindividualpersonisatonetimewhite，atanotherblack，atonetimewarm，atanothercold，atonetimegood，atanotherbad。Thiscapacityisfoundnowhereelse，thoughitmightbemaintainedthatastatementoropinionwasanexceptiontotherule。Thesamestatement，itisagreed，canbebothtrueandfalse。

Forifthestatement"heissitting"istrue，yet，whenthepersoninquestionhasrisen，thesamestatementwillbefalse。Thesameappliestoopinions。Forifanyonethinkstrulythatapersonissitting，yet，whenthatpersonhasrisen，thissameopinion，ifstillheld，willbefalse。Yetalthoughthisexceptionmaybeallowed，thereis，nevertheless，adifferenceinthemannerinwhichthethingtakesplace。Itisbythemselveschangingthatsubstancesadmitcontraryqualities。Itisthusthatthatwhichwashotbecomescold，forithasenteredintoadifferentstate。Similarlythatwhichwaswhitebecomesblack，andthatwhichwasbadgood，byaprocessofchange；andinthesamewayinallothercasesitisbychangingthatsubstancesarecapableofadmittingcontraryqualities。Butstatementsandopinionsthemselvesremainunalteredinallrespects：itisbythealterationinthefactsofthecasethatthecontraryqualitycomestobetheirs。Thestatement"heissitting"

remainsunaltered，butitisatonetimetrue，atanotherfalse，accordingtocircumstances。Whathasbeensaidofstatementsappliesalsotoopinions。Thus，inrespectofthemannerinwhichthethingtakesplace，itisthepeculiarmarkofsubstancethatitshouldbecapableofadmittingcontraryqualities；foritisbyitselfchangingthatitdoesso。

If，then，amanshouldmakethisexceptionandcontendthatstatementsandopinionsarecapableofadmittingcontraryqualities，hiscontentionisunsound。Forstatementsandopinionsaresaidtohavethiscapacity，notbecausetheythemselvesundergomodification，butbecausethismodificationoccursinthecaseofsomethingelse。Thetruthorfalsityofastatementdependsonfacts，andnotonanypoweronthepartofthestatementitselfofadmittingcontraryqualities。Inshort，thereisnothingwhichcanalterthenatureofstatementsandopinions。As，then，nochangetakesplaceinthemselves，thesecannotbesaidtobecapableofadmittingcontraryqualities。

Butitisbyreasonofthemodificationwhichtakesplacewithinthesubstanceitselfthatasubstanceissaidtobecapableofadmittingcontraryqualities；forasubstanceadmitswithinitselfeitherdiseaseorhealth，whitenessorblackness。Itisinthissensethatitissaidtobecapableofadmittingcontraryqualities。

Tosumup，itisadistinctivemarkofsubstance，that，whileremainingnumericallyoneandthesame，itiscapableofadmittingcontraryqualities，themodificationtakingplacethroughachangeinthesubstanceitself。

Lettheseremarkssufficeonthesubjectofsubstance。

Quantityiseitherdiscreteorcontinuous。Moreover，somequantitiesaresuchthateachpartofthewholehasarelativepositiontotheotherparts：othershavewithinthemnosuchrelationofparttopart。

Instancesofdiscretequantitiesarenumberandspeech；ofcontinuous，lines，surfaces，solids，and，besidesthese，timeandplace。

Inthecaseofthepartsofanumber，thereisnocommonboundaryatwhichtheyjoin。Forexample：twofivesmaketen，butthetwofiveshavenocommonboundary，butareseparate；thepartsthreeandsevenalsodonotjoinatanyboundary。Nor，togeneralize，woulditeverbepossibleinthecaseofnumberthatthereshouldbeacommonboundaryamongtheparts；theyarealwaysseparate。Number，therefore，isadiscretequantity。

Thesameistrueofspeech。Thatspeechisaquantityisevident：

foritismeasuredinlongandshortsyllables。Imeanherethatspeechwhichisvocal。Moreover，itisadiscretequantityforitspartshavenocommonboundary。Thereisnocommonboundaryatwhichthesyllablesjoin，buteachisseparateanddistinctfromtherest。

Aline，ontheotherhand，isacontinuousquantity，foritispossibletofindacommonboundaryatwhichitspartsjoin。Inthecaseoftheline，thiscommonboundaryisthepoint；inthecaseoftheplane，itistheline：forthepartsoftheplanehavealsoacommonboundary。Similarlyyoucanfindacommonboundaryinthecaseofthepartsofasolid，namelyeitheralineoraplane。

Spaceandtimealsobelongtothisclassofquantities。Time，past，present，andfuture，formsacontinuouswhole。Space，likewise，isacontinuousquantity；forthepartsofasolidoccupyacertainspace，andthesehaveacommonboundary；itfollowsthatthepartsofspacealso，whichareoccupiedbythepartsofthesolid，havethesamecommonboundaryasthepartsofthesolid。Thus，notonlytime，butspacealso，isacontinuousquantity，foritspartshaveacommonboundary。

Quantitiesconsisteitherofpartswhichbeararelativepositioneachtoeach，orofpartswhichdonot。Thepartsofalinebeararelativepositiontoeachother，foreachliessomewhere，anditwouldbepossibletodistinguisheach，andtostatethepositionofeachontheplaneandtoexplaintowhatsortofpartamongtheresteachwascontiguous。Similarlythepartsofaplanehaveposition，foritcouldsimilarlybestatedwhatwasthepositionofeachandwhatsortofpartswerecontiguous。Thesameistruewithregardtothesolidandtospace。Butitwouldbeimpossibletoshowthattheartsofanumberhadarelativepositioneachtoeach，oraparticularposition，ortostatewhatpartswerecontiguous。Norcouldthisbedoneinthecaseoftime，fornoneofthepartsoftimehasanabidingexistence，andthatwhichdoesnotabidecanhardlyhaveposition。

Itwouldbebettertosaythatsuchpartshadarelativeorder，invirtueofonebeingpriortoanother。Similarlywithnumber：incounting，"one"ispriorto"two"，and"two"to"three"，andthusthepartsofnumbermaybesaidtopossessarelativeorder，thoughitwouldbeimpossibletodiscoveranydistinctpositionforeach。Thisholdsgoodalsointhecaseofspeech。Noneofitspartshasanabidingexistence：whenonceasyllableispronounced，itisnotpossibletoretainit，sothat，naturally，asthepartsdonotabide，theycannothaveposition。Thus，somequantitiesconsistofpartswhichhaveposition，andsomeofthosewhichhavenot。

Strictlyspeaking，onlythethingswhichIhavementionedbelongtothecategoryofquantity：everythingelsethatiscalledquantitativeisaquantityinasecondarysense。Itisbecausewehaveinmindsomeoneofthesequantities，properlysocalled，thatweapplyquantitativetermstootherthings。Wespeakofwhatiswhiteaslarge，becausethesurfaceoverwhichthewhiteextendsislarge；wespeakofanactionoraprocessaslengthy，becausethetimecoveredislong；thesethingscannotintheirownrightclaimthequantitativeepithet。Forinstance，shouldanyoneexplainhowlonganactionwas，hisstatementwouldbemadeintermsofthetimetaken，totheeffectthatitlastedayear，orsomethingofthatsort。Inthesameway，hewouldexplainthesizeofawhiteobjectintermsofsurface，forhewouldstatetheareawhichitcovered。Thusthethingsalreadymentioned，andthesealone，areintheirintrinsicnaturequantities；nothingelsecanclaimthenameinitsownright，but，ifatall，onlyinasecondarysense。

Quantitieshavenocontraries。Inthecaseofdefinitequantitiesthisisobvious；thus，thereisnothingthatisthecontraryof"twocubitslong"orof"threecubitslong"，orofasurface，orofanysuchquantities。Amanmight，indeed，arguethat"much"wasthecontraryof"little"，and"great"of"small"。Butthesearenotquantitative，butrelative；thingsarenotgreatorsmallabsolutely，theyaresocalledratherastheresultofanactofcomparison。Forinstance，amountainiscalledsmall，agrainlarge，invirtueofthefactthatthelatterisgreaterthanothersofitskind，theformerless。Thusthereisareferenceheretoanexternalstandard，foriftheterms"great"and"small"wereusedabsolutely，amountainwouldneverbecalledsmalloragrainlarge。Again，wesaythattherearemanypeopleinavillage，andfewinAthens，althoughthoseinthecityaremanytimesasnumerousasthoseinthevillage：orwesaythatahousehasmanyinit，andatheatrefew，thoughthoseinthetheatrefaroutnumberthoseinthehouse。Theterms"twocubitslong，"threecubitslong，"andsoonindicatequantity，theterms"great"and"small"indicaterelation，fortheyhavereferencetoanexternalstandard。Itis，therefore，plainthatthesearetobeclassedasrelative。

Again，whetherwedefinethemasquantitativeornot，theyhavenocontraries：forhowcantherebeacontraryofanattributewhichisnottobeapprehendedinorbyitself，butonlybyreferencetosomethingexternal？Again，if"great"and"small"arecontraries，itwillcomeaboutthatthesamesubjectcanadmitcontraryqualitiesatoneandthesametime，andthatthingswillthemselvesbecontrarytothemselves。Forithappensattimesthatthesamethingisbothsmallandgreat。Forthesamethingmaybesmallincomparisonwithonething，andgreatincomparisonwithanother，sothatthesamethingcomestobebothsmallandgreatatoneandthesametime，andisofsuchanatureastoadmitcontraryqualitiesatoneandthesamemoment。Yetitwasagreed，whensubstancewasbeingdiscussed，thatnothingadmitscontraryqualitiesatoneandthesamemoment。Forthoughsubstanceiscapableofadmittingcontraryqualities，yetnooneisatthesametimebothsickandhealthy，nothingisatthesametimebothwhiteandblack。Noristhereanythingwhichisqualifiedincontrarywaysatoneandthesametime。

Moreover，ifthesewerecontraries，theywouldthemselvesbecontrarytothemselves。Forif"great"isthecontraryof"small"，andthesamethingisbothgreatandsmallatthesametime，then"small"or"great"isthecontraryofitself。Butthisisimpossible。Theterm"great"，therefore，isnotthecontraryoftheterm"small"，nor"much"of"little"。Andeventhoughamanshouldcallthesetermsnotrelativebutquantitative，theywouldnothavecontraries。

Itisinthecaseofspacethatquantitymostplausiblyappearstoadmitofacontrary。Formendefinetheterm"above"asthecontraryof"below"，whenitistheregionatthecentretheymeanby"below"；andthisisso，becausenothingisfartherfromtheextremitiesoftheuniversethantheregionatthecentre。Indeed，itseemsthatindefiningcontrariesofeverykindmenhaverecoursetoaspatialmetaphor，fortheysaythatthosethingsarecontrarieswhich，withinthesameclass，areseparatedbythegreatestpossibledistance。

Quantitydoesnot，itappears，admitofvariationofdegree。Onethingcannotbetwocubitslonginagreaterdegreethananother。

Similarlywithregardtonumber：whatis"three"isnotmoretrulythreethanwhatis"five"isfive；norisonesetofthreemoretrulythreethananotherset。Again，oneperiodoftimeisnotsaidtobemoretrulytimethananother。Noristhereanyotherkindofquantity，ofallthathavebeenmentioned，withregardtowhichvariationofdegreecanbepredicated。Thecategoryofquantity，therefore，doesnotadmitofvariationofdegree。

Themostdistinctivemarkofquantityisthatequalityandinequalityarepredicatedofit。Eachoftheaforesaidquantitiesissaidtobeequalorunequal。Forinstance，onesolidissaidtobeequalorunequaltoanother；number，too，andtimecanhavethesetermsappliedtothem，indeedcanallthosekindsofquantitythathavebeenmentioned。

Thatwhichisnotaquantitycanbynomeans，itwouldseem，betermedequalorunequaltoanythingelse。Oneparticulardispositionoroneparticularquality，suchaswhiteness，isbynomeanscomparedwithanotherintermsofequalityandinequalitybutratherintermsofsimilarity。Thusitisthedistinctivemarkofquantitythatitcanbecalledequalandunequal。

Thosethingsarecalledrelative，which，beingeithersaidtobeofsomethingelseorrelatedtosomethingelse，areexplainedbyreferencetothatotherthing。Forinstance，theword"superior"isexplainedbyreferencetosomethingelse，foritissuperiorityoversomethingelsethatismeant。Similarly，theexpression"double"hasthisexternalreference，foritisthedoubleofsomethingelsethatismeant。Soitiswitheverythingelseofthiskind。Thereare，moreover，otherrelatives，e。g。habit，disposition，perception，knowledge，andattitude。Thesignificanceofalltheseisexplainedbyareferencetosomethingelseandinnootherway。Thus，ahabitisahabitofsomething，knowledgeisknowledgeofsomething，attitudeistheattitudeofsomething。Soitiswithallotherrelativesthathavebeenmentioned。Thoseterms，then，arecalledrelative，thenatureofwhichisexplainedbyreferencetosomethingelse，thepreposition"of"orsomeotherprepositionbeingusedtoindicatetherelation。Thus，onemountainiscalledgreatincomparisonwithsonwithanother；forthemountainclaimsthisattributebycomparisonwithsomething。Again，thatwhichiscalledsimilarmustbesimilartosomethingelse，andallothersuchattributeshavethisexternalreference。Itistobenotedthatlyingandstandingandsittingareparticularattitudes，butattitudeisitselfarelativeterm。Tolie，tostand，tobeseated，arenotthemselvesattitudes，buttaketheirnamefromtheaforesaidattitudes。

Itispossibleforrelativestohavecontraries。Thusvirtuehasacontrary，vice，thesebothbeingrelatives；knowledge，too，hasacontrary，ignorance。Butthisisnotthemarkofallrelatives；

"double"and"triple"havenocontrary，norindeedhasanysuchterm。

Italsoappearsthatrelativescanadmitofvariationofdegree。For"like"and"unlike"，"equal"and"unequal"，havethemodifications"more"and"less"appliedtothem，andeachoftheseisrelativeincharacter：fortheterms"like"and"unequal"bear"unequal"bearareferencetosomethingexternal。Yet，again，itisnoteveryrelativetermthatadmitsofvariationofdegree。Notermsuchas"double"admitsofthismodification。Allrelativeshavecorrelatives：

bytheterm"slave"wemeantheslaveofamaster，bytheterm"master"，themasterofaslave；by"double"，thedoubleofitshall；by"half"，thehalfofitsdouble；by"greater"，greaterthanthatwhichisless；by"less，"lessthanthatwhichisgreater。

Soitiswitheveryotherrelativeterm；butthecaseweusetoexpressthecorrelationdiffersinsomeinstances。Thus，byknowledgewemeanknowledgetheknowable；bytheknowable，thatwhichistobeapprehendedbyknowledge；byperception，perceptionoftheperceptible；bytheperceptible，thatwhichisapprehendedbyperception。

Sometimes，however，reciprocityofcorrelationdoesnotappeartoexist。Thiscomesaboutwhenablunderismade，andthattowhichtherelativeisrelatedisnotaccuratelystated。Ifamanstatesthatawingisnecessarilyrelativetoabird，theconnexionbetweenthesetwowillnotbereciprocal，foritwillnotbepossibletosaythatabirdisabirdbyreasonofitswings。Thereasonisthattheoriginalstatementwasinaccurate，forthewingisnotsaidtoberelativetothebirdquabird，sincemanycreaturesbesidesbirdshavewings，butquawingedcreature。If，then，thestatementismadeaccurate，theconnexionwillbereciprocal，forwecanspeakofawing，havingreferencenecessarilytoawingedcreature，andofawingedcreatureasbeingsuchbecauseofitswings。

Occasionally，perhaps，itisnecessarytocoinwords，ifnowordexistsbywhichacorrelationcanadequatelybeexplained。Ifwedefinearudderasnecessarilyhavingreferencetoaboat，ourdefinitionwillnotbeappropriate，fortherudderdoesnothavethisreferencetoaboatquaboat，asthereareboatswhichhavenorudders。Thuswecannotusethetermsreciprocally，fortheword"boat"cannotbesaidtofinditsexplanationintheword"rudder"。Asthereisnoexistingword，ourdefinitionwouldperhapsbemoreaccurateifwecoinedsomewordlike"ruddered"asthecorrelativeof"rudder"。Ifweexpressourselvesthusaccurately，atanyratethetermsarereciprocallyconnected，forthe"ruddered"thingis"ruddered"invirtueofitsrudder。Soitisinallothercases。A

headwillbemoreaccuratelydefinedasthecorrelativeofthatwhichis"headed"，thanasthatofananimal，fortheanimaldoesnothaveaheadquaanimal，sincemanyanimalshavenohead。

Thuswemayperhapsmosteasilycomprehendthattowhichathingisrelated，whenanamedoesnotexist，if，fromthatwhichhasaname，wederiveanewname，andapplyittothatwithwhichthefirstisreciprocallyconnected，asintheaforesaidinstances，whenwederivedtheword"winged"from"wing"andfrom"rudder"。

Allrelatives，then，ifproperlydefined，haveacorrelative。I

addthisconditionbecause，ifthattowhichtheyarerelatedisstatedashaphazardandnotaccurately，thetwoarenotfoundtobeinterdependent。LetmestatewhatImeanmoreclearly。Eveninthecaseofacknowledgedcorrelatives，andwherenamesexistforeach，therewillbenointerdependenceifoneofthetwoisdenoted，notbythatnamewhichexpressesthecorrelativenotion，butbyoneofirrelevantsignificance。Theterm"slave，"ifdefinedasrelated，nottoamaster，buttoaman，orabiped，oranythingofthatsort，isnotreciprocallyconnectedwiththatinrelationtowhichitisdefined，forthestatementisnotexact。Further，ifonethingissaidtobecorrelativewithanother，andtheterminologyusediscorrect，then，thoughallirrelevantattributesshouldberemoved，andonlythatoneattributeleftinvirtueofwhichitwascorrectlystatedtobecorrelativewiththatother，thestatedcorrelationwillstillexist。Ifthecorrelativeof"theslave"issaidtobe"themaster"，then，thoughallirrelevantattributesofthesaid"master"，suchas"biped"，"receptiveofknowledge"，"human"，shouldberemoved，andtheattribute"master"aloneleft，thestatedcorrelationexistingbetweenhimandtheslavewillremainthesame，foritisofamasterthataslaveissaidtobetheslave。Ontheotherhand，if，oftwocorrelatives，oneisnotcorrectlytermed，then，whenallotherattributesareremovedandthataloneisleftinvirtueofwhichitwasstatedtobecorrelative，thestatedcorrelationwillbefoundtohavedisappeared。

Forsupposethecorrelativeof"theslave"shouldbesaidtobe"theman"，orthecorrelativeof"thewing"thebird"；iftheattribute"master"bewithdrawnfrom"theman"，thecorrelationbetween"theman"and"theslave"willceasetoexist，forifthemanisnotamaster，theslaveisnotaslave。Similarly，iftheattribute"winged"

bewithdrawnfrom"thebird"，"thewing"willnolongerberelative；

foriftheso-calledcorrelativeisnotwinged，itfollowsthat"thewing"hasnocorrelative。

Thusitisessentialthatthecorrelatedtermsshouldbeexactlydesignated；ifthereisanameexisting，thestatementwillbeeasy；

ifnot，itisdoubtlessourdutytoconstructnames。Whentheterminologyisthuscorrect，itisevidentthatallcorrelativesareinterdependent。

Correlativesarethoughttocomeintoexistencesimultaneously。Thisisforthemostparttrue，asinthecaseofthedoubleandthehalf。Theexistenceofthehalfnecessitatestheexistenceofthatofwhichitisahalf。Similarlytheexistenceofamasternecessitatestheexistenceofaslave，andthatofaslaveimpliesthatofamaster；thesearemerelyinstancesofageneralrule。

Moreover，theycanceloneanother；forifthereisnodoubleitfollowsthatthereisnohalf，andviceversa；thisrulealsoappliestoallsuchcorrelatives。Yetitdoesnotappeartobetrueinallcasesthatcorrelativescomeintoexistencesimultaneously。Theobjectofknowledgewouldappeartoexistbeforeknowledgeitself，foritisusuallythecasethatweacquireknowledgeofobjectsalreadyexisting；itwouldbedifficult，ifnotimpossible，tofindabranchofknowledgethebeginningoftheexistenceofwhichwascontemporaneouswiththatofitsobject。

Again，whiletheobjectofknowledge，ifitceasestoexist，cancelsatthesametimetheknowledgewhichwasitscorrelative，theconverseofthisisnottrue。Itistruethatiftheobjectofknowledgedoesnotexisttherecanbenoknowledge：fortherewillnolongerbeanythingtoknow。Yetitisequallytruethat，ifknowledgeofacertainobjectdoesnotexist，theobjectmayneverthelessquitewellexist。Thus，inthecaseofthesquaringofthecircle，ifindeedthatprocessisanobjectofknowledge，thoughititselfexistsasanobjectofknowledge，yettheknowledgeofithasnotyetcomeintoexistence。Again，ifallanimalsceasedtoexist，therewouldbenoknowledge，buttheremightyetbemanyobjectsofknowledge。

Thisislikewisethecasewithregardtoperception：fortheobjectofperceptionis，itappears，priortotheactofperception。

Iftheperceptibleisannihilated，perceptionalsowillceasetoexist；buttheannihilationofperceptiondoesnotcanceltheexistenceoftheperceptible。Forperceptionimpliesabodyperceivedandabodyinwhichperceptiontakesplace。Nowifthatwhichisperceptibleisannihilated，itfollowsthatthebodyisannihilated，forthebodyisaperceptiblething；andifthebodydoesnotexist，itfollowsthatperceptionalsoceasestoexist。Thustheannihilationoftheperceptibleinvolvesthatofperception。

Buttheannihilationofperceptiondoesnotinvolvethatoftheperceptible。Foriftheanimalisannihilated，itfollowsthatperceptionalsoisannihilated，butperceptiblessuchasbody，heat，sweetness，bitterness，andsoon，willremain。

Again，perceptionisgeneratedatthesametimeastheperceivingsubject，foritcomesintoexistenceatthesametimeastheanimal。

Buttheperceptiblesurelyexistsbeforeperception；forfireandwaterandsuchelements，outofwhichtheanimalisitselfcomposed，existbeforetheanimalisananimalatall，andbeforeperception。

Thusitwouldseemthattheperceptibleexistsbeforeperception。