othersthinktheyareofthelattercharacter。Platoandthe
  Pythagoreansthoughtbeingandunitywerenothingelse,butthiswas
  theirnature,theiressencebeingjustunityandbeing。Butthe
  naturalphilosopherstakeadifferentline;e。g。Empedocles-as
  thoughreducingtosomethingmoreintelligible-sayswhatunityis;for
  hewouldseemtosayitislove:atleast,thisisforallthings
  thecauseoftheirbeingone。Otherssaythisunityandbeing,of
  whichthingsconsistandhavebeenmade,isfire,andotherssayitis
  air。Asimilarviewisexpressedbythosewhomaketheelementsmore
  thanone;forthesealsomustsaythatunityandbeingareprecisely
  allthethingswhichtheysayareprinciples。
  AIfwedonotsupposeunityandbeingtobesubstances,it
  followsthatnoneoftheotheruniversalsisasubstance;forthese
  aremostuniversalofall,andifthereisnounityitselfor
  being-itself,therewillscarcelybeinanyothercaseanything
  apartfromwhatarecalledtheindividuals。Further,ifunityisnota
  substance,evidentlynumberalsowillnotexistasanentity
  separatefromtheindividualthings;fornumberisunits,andtheunit
  ispreciselyacertainkindofone。
  ButBifthereisaunity-itselfandabeingitself,unityand
  beingmustbetheirsubstance;foritisnotsomethingelsethatis
  predicateduniversallyofthethingsthatareandareone,butjust
  unityandbeing。Butifthereistobeabeing-itselfanda
  unity-itself,thereismuchdifficultyinseeinghowtherewillbe
  anythingelsebesidesthese,-Imean,howthingswillbemorethan
  oneinnumber。Forwhatisdifferentfrombeingdoesnotexist,so
  thatitnecessarilyfollows,accordingtotheargumentof
  Parmenides,thatallthingsthatareareoneandthisisbeing。
  Thereareobjectionstobothviews。Forwhetherunityisnota
  substanceorthereisaunity-itself,numbercannotbeasubstance。We
  havealreadysaidwhythisresultfollowsifunityisnotasubstance;
  andifitis,thesamedifficultyarisesasarosewithregardto
  being。Forwhenceistheretobeanotheronebesidesunity-itself?
  Itmustbenot-one;butallthingsareeitheroneormany,andof
  themanyeachisone。
  Further,ifunity-itselfisindivisible,accordingtoZeno’s
  postulateitwillbenothing。Forthatwhichneitherwhenadded
  makesathinggreaternorwhensubtractedmakesitless,heassertsto
  havenobeing,evidentlyassumingthatwhateverhasbeingisaspatial
  magnitude。Andifitisamagnitude,itiscorporeal;forthe
  corporealhasbeingineverydimension,whiletheotherobjectsof
  mathematics,e。g。aplaneoraline,addedinonewaywillincrease
  whattheyareaddedto,butinanotherwaywillnotdoso,andapoint
  oraunitdoessoinnoway。But,sincehistheoryisofalow
  order,andanindivisiblethingcanexistinsuchawayastohavea
  defenceevenagainsthimfortheindivisiblewhenaddedwillmakethe
  number,thoughnotthesize,greater,-yethowcanamagnitudeproceed
  fromonesuchindivisibleorfrommany?Itislikesayingthatthe
  lineismadeoutofpoints。
  Buteveniforesupposesthecasetobesuchthat,assomesay,
  numberproceedsfromunity-itselfandsomethingelsewhichisnotone,
  nonethelesswemustinquirewhyandhowtheproductwillbe
  sometimesanumberandsometimesamagnitude,ifthenot-onewas
  inequalityandwasthesameprincipleineithercase。Foritisnot
  evidenthowmagnitudescouldproceedeitherfromtheoneandthis
  principle,orfromsomenumberandthisprinciple。
  14Aquestionconnectedwiththeseiswhethernumbersandbodies
  andplanesandpointsaresubstancesofakind,ornot。Iftheyare
  not,itbafflesustosaywhatbeingisandwhatthesubstancesof
  thingsare。Formodificationsandmovementsandrelationsand
  dispositionsandratiosdonotseemtoindicatethesubstanceof
  anything;forallarepredicatedofasubject,andnoneisa’this’。
  Andastothethingswhichmightseemmostofalltoindicate
  substance,waterandearthandfireandair,ofwhichcompositebodies
  consist,heatandcoldandthelikearemodificationsofthese,not
  substances,andthebodywhichisthusmodifiedalonepersistsas
  somethingrealandasasubstance。But,ontheotherhand,thebodyis
  surelylessofasubstancethanthesurface,andthesurfacethan
  theline,andthelinethantheunitandthepoint。Forthebodyis
  boundedbythese;andtheyarethoughttobecapableofexisting
  withoutbody,butbodyincapableofexistingwithoutthese。Thisis
  why,whilemostofthephilosophersandtheearlieramongthemthought
  thatsubstanceandbeingwereidenticalwithbody,andthatall
  otherthingsweremodificationsofthis,sothatthefirst
  principlesofthebodieswerethefirstprinciplesofbeing,the
  morerecentandthosewhowereheldtobewiserthoughtnumberswere
  thefirstprinciples。Aswesaid,then,ifthesearenotsubstance,
  thereisnosubstanceandnobeingatall;fortheaccidentsof
  theseitcannotberighttocallbeings。
  Butifthisisadmitted,thatlinesandpointsaresubstance
  morethanbodies,butwedonotseetowhatsortofbodiesthesecould
  belongfortheycannotbeinperceptiblebodies,therecanbeno
  substance-Further,theseareallevidentlydivisionsofbody,-one
  inbreadth,anotherindepth,anotherinlength。Besidesthis,nosort
  ofshapeispresentinthesolidmorethananyother;sothatifthe
  Hermesisnotinthestone,neitheristhehalfofthecubeinthe
  cubeassomethingdeterminate;thereforethesurfaceisnotinit
  either;forifanysortofsurfacewereinit,thesurfacewhichmarks
  offthehalfofthecubewouldbeinittoo。Andthesameaccount
  appliestothelineandtothepointandtheunit。Therefore,ifon
  theonehandbodyisinthehighestdegreesubstance,andontheother
  handthesethingsaresomorethanbody,butthesearenoteven
  instancesofsubstance,itbafflesustosaywhatbeingisandwhat
  thesubstanceofthingsis-Forbesideswhathasbeensaid,the
  questionsofgenerationandinstructionconfrontuswithfurther
  paradoxes。Forifsubstance,nothavingexistedbefore,nowexists,or
  havingexistedbefore,afterwardsdoesnotexist,thischangeis
  thoughttobeaccompaniedbyaprocessofbecomingorperishing;but
  pointsandlinesandsurfacescannotbeinprocesseitherof
  becomingorofperishing,whentheyatonetimeexistandatanother
  donot。Forwhenbodiescomeintocontactoraredivided,their
  boundariessimultaneouslybecomeoneintheonecasewhenthey
  touch,andtwointheother-whentheyaredivided;sothatwhenthey
  havebeenputtogetheroneboundarydoesnotexistbuthasperished,
  andwhentheyhavebeendividedtheboundariesexistwhichbefore
  didnotexistforitcannotbesaidthatthepoint,whichis
  indivisible,wasdividedintotwo。Andiftheboundariescomeinto
  beingandceasetobe,fromwhatdotheycomeintobeing?Asimilar
  accountmayalsobegivenofthe’now’intime;forthisalsocannot
  beinprocessofcomingintobeingorofceasingtobe,butyet
  seemstobealwaysdifferent,whichshowsthatitisnota
  substance。Andevidentlythesameistrueofpointsandlinesand
  planes;forthesameargumentapplies,sincetheyareallalikeeither
  limitsordivisions。
  Ingeneralonemightraisethequestionwhyafterall,besides
  perceptiblethingsandtheintermediates,wehavetolookfor
  anotherclassofthings,i。e。theFormswhichweposit。Ifitisfor
  thisreason,becausetheobjectsofmathematics,whiletheydiffer
  fromthethingsinthisworldinsomeotherrespect,differnotatall
  inthattherearemanyofthesamekind,sothattheirfirst
  principlescannotbelimitedinnumberjustastheelementsofall
  thelanguageinthissensibleworldarenotlimitedinnumber,but
  inkind,unlessonetakestheelementsofthisindividualsyllable
  orofthisindividualarticulatesound-whoseelementswillbe
  limitedeveninnumber;soisitalsointhecaseofthe
  intermediates;fortherealsothemembersofthesamekindare
  infiniteinnumber,sothatiftherearenot-besidesperceptible
  andmathematicalobjects-otherssuchassomemaintaintheFormstobe,
  therewillbenosubstancewhichisoneinnumber,butonlyinkind,
  norwillthefirstprinciplesofthingsbedeterminateinnumber,
  butonlyinkind:-ifthenthismustbeso,theFormsalsomust
  thereforebeheldtoexist。Evenifthosewhosupportthisviewdonot
  expressitarticulately,stillthisiswhattheymean,andtheymust
  bemaintainingtheFormsjustbecauseeachoftheFormsisasubstance
  andnoneisbyaccident。
  ButifwearetosupposeboththattheFormsexistandthatthe
  principlesareoneinnumber,notinkind,wehavementionedthe
  impossibleresultsthatnecessarilyfollow。
  13Closelyconnectedwiththisisthequestionwhetherthe
  elementsexistpotentiallyorinsomeothermanner。Ifinsomeother
  way,therewillbesomethingelsepriortothefirstprinciples;for
  thepotencyispriortotheactualcause,anditisnotnecessary
  foreverythingpotentialtobeactual-Butiftheelementsexist
  potentially,itispossiblethateverythingthatisshouldnotbe。For
  eventhatwhichisnotyetiscapableofbeing;forthatwhichis
  notcomestobe,butnothingthatisincapableofbeingcomestobe。
  12Wemustnotonlyraisethesequestionsaboutthefirst
  principles,butalsoaskwhethertheyareuniversalorwhatwecall
  individuals。Iftheyareuniversal,theywillnotbesubstances;for
  everythingthatiscommonindicatesnota’this’buta’such’,but
  substanceisa’this’。Andifwearetobeallowedtolayitdownthat
  acommonpredicateisa’this’andasinglething,Socrateswillbe
  severalanimals-himselfand’man’and’animal’,ifeachofthese
  indicatesa’this’andasinglething。
  If,then,theprinciplesareuniversals,theseuniversal。
  Thereforeifthereistoberesultsfollow;iftheyarenotuniversals
  butofknowledgeoftheprinciplestheremustbethenatureof
  individuals,theywillnotbeotherprinciplespriortothem,namely
  thoseknowable;fortheknowledgeofanythingisthatare
  universallypredicatedofthem。
  THEREisasciencewhichinvestigatesbeingasbeingandthe
  attributeswhichbelongtothisinvirtueofitsownnature。Now
  thisisnotthesameasanyoftheso-calledspecialsciences;for
  noneoftheseotherstreatsuniversallyofbeingasbeing。Theycut
  offapartofbeingandinvestigatetheattributeofthispart;this
  iswhatthemathematicalsciencesforinstancedo。Nowsinceweare
  seekingthefirstprinciplesandthehighestcauses,clearlythere
  mustbesomethingtowhichthesebelonginvirtueofitsown
  nature。Ifthenthosewhosoughttheelementsofexistingthings
  wereseekingthesesameprinciples,itisnecessarythatthe
  elementsmustbeelementsofbeingnotbyaccidentbutjustbecauseit
  isbeing。Thereforeitisofbeingasbeingthatwealsomustgrasp
  thefirstcauses。