第1章

1

WHENtheobjectsofaninquiry，inanydepartment，haveprinciples，conditions，orelements，itisthroughacquaintancewiththesethatknowledge，thatistosayscientificknowledge，isattained。Forwedonotthinkthatweknowathinguntilweareacquaintedwithitsprimaryconditionsorfirstprinciples，andhavecarriedouranalysisasfarasitssimplestelements。PlainlythereforeinthescienceofNature，asinotherbranchesofstudy，ourfirsttaskwillbetotrytodeterminewhatrelatestoitsprinciples。

Thenaturalwayofdoingthisistostartfromthethingswhicharemoreknowableandobvioustousandproceedtowardsthosewhichareclearerandmoreknowablebynature；forthesamethingsarenot"knowablerelativelytous"and"knowable"withoutqualification。Sointhepresentinquirywemustfollowthismethodandadvancefromwhatismoreobscurebynature，butclearertous，towardswhatismoreclearandmoreknowablebynature。

Nowwhatistousplainandobviousatfirstisratherconfusedmasses，theelementsandprinciplesofwhichbecomeknowntouslaterbyanalysis。Thuswemustadvancefromgeneralitiestoparticulars；foritisawholethatisbestknowntosense-perception，andageneralityisakindofwhole，comprehendingmanythingswithinit，likeparts。Muchthesamethinghappensintherelationofthenametotheformula。Aname，e。g。"round"，meansvaguelyasortofwhole:itsdefinitionanalysesthisintoitsparticularsenses。

Similarlyachildbeginsbycallingallmen"father"，andallwomen"mother"，butlaterondistinguisheseachofthem。

2

Theprinciplesinquestionmustbeeither(a)oneor(b)morethanone。If(a)one，itmustbeeither(i)motionless，asParmenidesandMelissusassert，or(ii)inmotion，asthephysicistshold，somedeclaringairtobethefirstprinciple，otherswater。If(b)morethanone，theneither(i)afiniteor(ii)aninfiniteplurality。If(i)finite(butmorethanone)，theneithertwoorthreeorfourorsomeothernumber。If(ii)infinite，theneitherasDemocritusbelievedoneinkind，butdifferinginshapeorform；ordifferentinkindandevencontrary。

Asimilarinquiryismadebythosewhoinquireintothenumberofexistents:fortheyinquirewhethertheultimateconstituentsofexistingthingsareoneormany，andifmany，whetherafiniteoraninfiniteplurality。Sotheytooareinquiringwhethertheprincipleorelementisoneormany。

NowtoinvestigatewhetherBeingisoneandmotionlessisnotacontributiontothescienceofNature。Forjustasthegeometerhasnothingmoretosaytoonewhodeniestheprinciplesofhisscience-thisbeingaquestionforadifferentscienceorfororcommontoall-soamaninvestigatingprinciplescannotarguewithonewhodeniestheirexistence。ForifBeingisjustone，andoneinthewaymentioned，thereisaprinciplenolonger，sinceaprinciplemustbetheprincipleofsomethingorthings。

ToinquirethereforewhetherBeingisoneinthissensewouldbelikearguingagainstanyotherpositionmaintainedforthesakeofargument(suchastheHeracliteanthesis，orsuchathesisasthatBeingisoneman)orlikerefutingamerelycontentiousargument-adescriptionwhichappliestotheargumentsbothofMelissusandofParmenides:theirpremissesarefalseandtheirconclusionsdonotfollow。OrrathertheargumentofMelissusisgrossandpalpableandoffersnodifficultyatall:acceptoneridiculouspropositionandtherestfollows-asimpleenoughproceeding。

Wephysicists，ontheotherhand，musttakeforgrantedthatthethingsthatexistbynatureare，eitherallorsomeofthem，inmotionwhichisindeedmadeplainbyinduction。Moreover，nomanofscienceisboundtosolveeverykindofdifficultythatmayberaised，butonlyasmanyasaredrawnfalselyfromtheprinciplesofthescience:itisnotourbusinesstorefutethosethatdonotariseinthisway:justasitisthedutyofthegeometertorefutethesquaringofthecirclebymeansofsegments，butitisnothisdutytorefuteAntiphon"sproof。Atthesametimetheholdersofthetheoryofwhichwearespeakingdoincidentallyraisephysicalquestions，thoughNatureisnottheirsubject:soitwillperhapsbeaswelltospendafewwordsonthem，especiallyastheinquiryisnotwithoutscientificinterest。

Themostpertinentquestionwithwhichtobeginwillbethis:Inwhatsenseisitassertedthatallthingsareone?For"is"isusedinmanysenses。Dotheymeanthatallthings"are"substanceorquantitiesorqualities?And，further，areallthingsonesubstance-oneman，onehorse，oronesoul-orqualityandthatoneandthesame-whiteorhotorsomethingofthekind?Theseareallverydifferentdoctrinesandallimpossibletomaintain。

Forifbothsubstanceandquantityandqualityare，then，whethertheseexistindependentlyofeachotherornot，Beingwillbemany。

Ifontheotherhanditisassertedthatallthingsarequalityorquantity，then，whethersubstanceexistsornot，anabsurdityresults，iftheimpossiblecanproperlybecalledabsurd。Fornoneoftheotherscanexistindependently:substancealoneisindependent:foreverythingispredicatedofsubstanceassubject。NowMelissussaysthatBeingisinfinite。Itisthenaquantity。Fortheinfiniteisinthecategoryofquantity，whereassubstanceorqualityoraffectioncannotbeinfiniteexceptthroughaconcomitantattribute，thatis，ifatthesametimetheyarealsoquantities。Fortodefinetheinfiniteyoumustusequantityinyourformula，butnotsubstanceorquality。IfthenBeingisbothsubstanceandquantity，itistwo，notone:ifonlysubstance，itisnotinfiniteandhasnomagnitude；

fortohavethatitwillhavetobeaquantity。

Again，"one"itself，nolessthan"being"，isusedinmanysenses，sowemustconsiderinwhatsensethewordisusedwhenitissaidthattheAllisone。

Nowwesaythat(a)thecontinuousisoneorthat(b)theindivisibleisone，or(c)thingsaresaidtobe"one"，whentheiressenceisoneandthesame，as"liquor"and"drink"。

If(a)theirOneisoneinthesenseofcontinuous，itismany，forthecontinuousisdivisibleadinfinitum。

Thereis，indeed，adifficultyaboutpartandwhole，perhapsnotrelevanttothepresentargument，yetdeservingconsiderationonitsownaccount-namely，whetherthepartandthewholeareoneormorethanone，andhowtheycanbeoneormany，and，iftheyaremorethanone，inwhatsensetheyaremorethanone。(Similarlywiththepartsofwholeswhicharenotcontinuous。)Further，ifeachofthetwopartsisindivisiblyonewiththewhole，thedifficultyarisesthattheywillbeindivisiblyonewitheachotheralso。

Buttoproceed:If(b)theirOneisoneasindivisible，nothingwillhavequantityorquality，andsotheonewillnotbeinfinite，asMelissussays-nor，indeed，limited，asParmenidessays，forthoughthelimitisindivisible，thelimitedisnot。

Butif(c)allthingsareoneinthesenseofhavingthesamedefinition，like"raiment"and"dress"，thenitturnsoutthattheyaremaintainingtheHeracliteandoctrine，foritwillbethesamething"tobegood"and"tobebad"，and"tobegood"and"tobenotgood"，andsothesamethingwillbe"good"and"notgood"，andmanandhorse；infact，theirviewwillbe，notthatallthingsareone，butthattheyarenothing；andthat"tobeofsuch-and-suchaquality"

isthesameas"tobeofsuch-and-suchasize"。

Eventhemorerecentoftheancientthinkerswereinapotherlestthesamethingshouldturnoutintheirhandsbothoneandmany。Sosome，likeLycophron，wereledtoomit"is"，otherstochangethemodeofexpressionandsay"themanhasbeenwhitened"insteadof"iswhite"，and"walks"insteadof"iswalking"，forfearthatiftheyaddedtheword"is"theyshouldbemakingtheonetobemany-asif"one"and"being"werealwaysusedinoneandthesamesense。What"is"maybemanyeitherindefinition(forexample"tobewhite"isonething，"tobemusical"another，yetthesamethingbeboth，sotheoneismany)orbydivision，asthewholeanditsparts。Onthispoint，indeed，theywerealreadygettingintodifficultiesandadmittedthattheonewasmany-asiftherewasanydifficultyaboutthesamethingbeingbothoneandmany，providedthatthesearenotopposites；for"one"maymeaneither"potentiallyone"or"actuallyone"。

3

If，then，weapproachthethesisinthiswayitseemsimpossibleforallthingstobeone。Further，theargumentstheyusetoprovetheirpositionarenotdifficulttoexpose。Forbothofthemreasoncontentiously-ImeanbothMelissusandParmenides。[Theirpremissesarefalseandtheirconclusionsdonotfollow。OrrathertheargumentofMelissusisgrossandpalpableandoffersnodifficultyatall:admitoneridiculouspropositionandtherestfollows-asimpleenoughproceeding。]ThefallacyofMelissusisobvious。Forhesupposesthattheassumption"whathascomeintobeingalwayshasabeginning"justifiestheassumption"whathasnotcomeintobeinghasnobeginning"。Thenthisalsoisabsurd，thatineverycasethereshouldbeabeginningofthething-notofthetimeandnotonlyinthecaseofcomingtobeinthefullsensebutalsointhecaseofcomingtohaveaquality-asifchangenevertookplacesuddenly。Again，doesitfollowthatBeing，ifone，ismotionless?Whyshoulditnotmove，thewholeofitwithinitself，aspartsofitdowhichareunities，e。g。thiswater?Again，whyisqualitativechangeimpossible?But，further，Beingcannotbeoneinform，thoughitmaybeinwhatitismadeof。(Evensomeofthephysicistsholdittobeoneinthelatterway，thoughnotintheformer。)Manobviouslydiffersfromhorseinform，andcontrariesfromeachother。

ThesamekindofargumentholdsgoodagainstParmenidesalso，besidesanythatmayapplyspeciallytohisview:theanswertohimbeingthat"thisisnottrue"and"thatdoesnotfollow"。Hisassumptionthatoneisusedinasinglesenseonlyisfalse，becauseitisusedinseveral。Hisconclusiondoesnotfollow，becauseifwetakeonlywhitethings，andif"white"hasasinglemeaning，nonethelesswhatiswhitewillbemanyandnotone。Forwhatiswhitewillnotbeoneeitherinthesensethatitiscontinuousorinthesensethatitmustbedefinedinonlyoneway。"Whiteness"willbedifferentfrom"whathaswhiteness"。Nordoesthismeanthatthereisanythingthatcanexistseparately，overandabovewhatiswhite。

For"whiteness"and"thatwhichiswhite"differindefinition，notinthesensethattheyarethingswhichcanexistapartfromeachother。ButParmenideshadnotcomeinsightofthisdistinction。

Itisnecessaryforhim，then，toassumenotonlythat"being"hasthesamemeaning，ofwhateveritispredicated，butfurtherthatitmeans(1)whatjustisand(2)whatisjustone。

Itmustbeso，for(1)anattributeispredicatedofsomesubject，sothatthesubjecttowhich"being"isattributedwillnotbe，asitissomethingdifferentfrom"being"。Something，therefore，whichisnotwillbe。Hence"substance"willnotbeapredicateofanythingelse。Forthesubjectcannotbeabeing，unless"being"meansseveralthings，insuchawaythateachissomething。Butexhypothesi"being"meansonlyonething。

If，then，"substance"isnotattributedtoanything，butotherthingsareattributedtoit，howdoes"substance"meanwhatisratherthanwhatisnot?Forsupposethat"substance"isalso"white"。

Sincethedefinitionofthelatterisdifferent(forbeingcannotevenbeattributedtowhite，asnothingiswhichisnot"substance")，itfollowsthat"white"isnot-being——andthatnotinthesenseofaparticularnot-being，butinthesensethatitisnotatall。Hence"substance"isnot；foritistruetosaythatitiswhite，whichwefoundtomeannot-being。Iftoavoidthiswesaythateven"white"

meanssubstance，itfollowsthat"being"hasmorethanonemeaning。

Inparticular，then，Beingwillnothavemagnitude，ifitissubstance。Foreachofthetwopartsmustheinadifferentsense。

(2)Substanceisplainlydivisibleintoothersubstances，ifweconsiderthemerenatureofadefinition。Forinstance，if"man"isasubstance，"animal"and"biped"mustalsobesubstances。Forifnotsubstances，theymustbeattributes-andifattributes，attributeseitherof(a)manorof(b)someothersubject。Butneitherispossible。

(a)Anattributeiseitherthatwhichmayormaynotbelongtothesubjectorthatinwhosedefinitionthesubjectofwhichitisanattributeisinvolved。Thus"sitting"isanexampleofaseparableattribute，while"snubness"containsthedefinitionof"nose"，towhichweattributesnubness。Further，thedefinitionofthewholeisnotcontainedinthedefinitionsofthecontentsorelementsofthedefinitoryformula；thatof"man"forinstancein"biped"，orthatof"whiteman"in"white"。Ifthenthisisso，andif"biped"issupposedtobeanattributeof"man"，itmustbeeitherseparable，sothat"man"mightpossiblynotbe"biped"，orthedefinitionof"man"mustcomeintothedefinitionof"biped"-whichisimpossible，astheconverseisthecase。

(b)If，ontheotherhand，wesupposethat"biped"and"animal"

areattributesnotofmanbutofsomethingelse，andarenoteachofthemasubstance，then"man"toowillbeanattributeofsomethingelse。Butwemustassumethatsubstanceisnottheattributeofanything，thatthesubjectofwhichboth"biped"and"animal"andeachseparatelyarepredicatedisthesubjectalsoofthecomplex"bipedanimal"。

ArewethentosaythattheAlliscomposedofindivisiblesubstances?Somethinkersdid，inpointoffact，givewaytobotharguments。Totheargumentthatallthingsareoneifbeingmeansonething，theyconcededthatnot-beingis；tothatfrombisection，theyyieldedbypositingatomicmagnitudes。Butobviouslyitisnottruethatifbeingmeansonething，andcannotatthesametimemeanthecontradictoryofthis，therewillbenothingwhichisnot，forevenifwhatisnotcannotbewithoutqualification，thereisnoreasonwhyitshouldnotbeaparticularnot-being。Tosaythatallthingswillbeone，ifthereisnothingbesidesBeingitself，isabsurd。Forwhounderstands"beingitself"tobeanythingbutaparticularsubstance?Butifthisisso，thereisnothingtopreventtherebeingmanybeings，ashasbeensaid。

Itis，then，clearlyimpossibleforBeingtobeoneinthissense。

4

Thephysicistsontheotherhandhavetwomodesofexplanation。

Thefirstsetmaketheunderlyingbodyoneeitheroneofthethreeorsomethingelsewhichisdenserthanfireandrarerthanairthengenerateeverythingelsefromthis，andobtainmultiplicitybycondensationandrarefaction。Nowthesearecontraries，whichmaybegeneralizedinto"excessanddefect"。(ComparePlato"s"GreatandSmall"-exceptthathemakethesehismatter，theonehisform，whiletheotherstreattheonewhichunderliesasmatterandthecontrariesasdifferentiae，i。e。forms)。

Thesecondsetassertthatthecontrarietiesarecontainedintheoneandemergefromitbysegregation，forexampleAnaximanderandalsoallthosewhoassertthat"whatis"isoneandmany，likeEmpedoclesandAnaxagoras；fortheytooproduceotherthingsfromtheirmixturebysegregation。Thesediffer，however，fromeachotherinthattheformerimaginesacycleofsuchchanges，thelatterasingleseries。Anaxagorasagainmadebothhis"homceomerous"

substancesandhiscontrariesinfiniteinmultitude，whereasEmpedoclespositsonlytheso-calledelements。

ThetheoryofAnaxagorasthattheprinciplesareinfiniteinmultitudewasprobablyduetohisacceptanceofthecommonopinionofthephysiciststhatnothingcomesintobeingfromnot-being。Forthisisthereasonwhytheyusethephrase"allthingsweretogether"andthecomingintobeingofsuchandsuchakindofthingisreducedtochangeofquality，whilesomespokeofcombinationandseparation。Moreover，thefactthatthecontrariesproceedfromeachotherledthemtotheconclusion。Theone，theyreasoned，musthavealreadyexistedintheother；forsinceeverythingthatcomesintobeingmustariseeitherfromwhatisorfromwhatisnot，anditisimpossibleforittoarisefromwhatisnot(onthispointallthephysicistsagree)，theythoughtthatthetruthofthealternativenecessarilyfollowed，namelythatthingscomeintobeingoutofexistentthings，i。e。outofthingsalreadypresent，butimperceptibletooursensesbecauseofthesmallnessoftheirbulk。Sotheyassertthateverythinghasbeenmixedinevery。thing，becausetheysaweverythingarisingoutofeverything。Butthings，astheysay，appeardifferentfromoneanotherandreceivedifferentnamesaccordingtothenatureoftheparticleswhicharenumericallypredominantamongtheinnumerableconstituentsofthemixture。Fornothing，theysay，ispurelyandentirelywhiteorblackorsweet，boneorflesh，butthenatureofathingisheldtobethatofwhichitcontainsthemost。

Now(1)theinfinitequainfiniteisunknowable，sothatwhatisinfiniteinmultitudeorsizeisunknowableinquantity，andwhatisinfiniteinvarietyofkindisunknowableinquality。Buttheprinciplesinquestionareinfinitebothinmultitudeandinkind。

Thereforeitisimpossibletoknowthingswhicharecomposedofthem；foritiswhenweknowthenatureandquantityofitscomponentsthatwesupposeweknowacomplex。

Further(2)ifthepartsofawholemaybeofanysizeinthedirectioneitherofgreatnessorofsmallness(by"parts"Imeancomponentsintowhichawholecanbedividedandwhichareactuallypresentinit)，itisnecessarythatthewholethingitselfmaybeofanysize。Clearly，therefore，sinceitisimpossibleforananimalorplanttobeindefinitelybigorsmall，neithercanitspartsbesuch，orthewholewillbethesame。Butflesh，bone，andthelikearethepartsofanimals，andthefruitsarethepartsofplants。

Henceitisobviousthatneitherflesh，bone，noranysuchthingcanbeofindefinitesizeinthedirectioneitherofthegreateroroftheless。

Again(3)accordingtothetheoryallsuchthingsarealreadypresentinoneanotheranddonotcomeintobeingbutareconstituentswhichareseparatedout，andathingreceivesitsdesignationfromitschiefconstituent。Further，anythingmaycomeoutofanything-waterbysegregationfromfleshandfleshfromwater。Hence，sinceeveryfinitebodyisexhaustedbytherepeatedabstractionofafinitebody，itseemsobviouslytofollowthateverythingcannotsubsistineverythingelse。Forletfleshbeextractedfromwaterandagainmorefleshbeproducedfromtheremainderbyrepeatingtheprocessofseparation:

then，eventhoughthequantityseparatedoutwillcontinuallydecrease，stillitwillnotfallbelowacertainmagnitude。If，therefore，theprocesscomestoanend，everythingwillnotbeineverythingelse(fortherewillbenofleshintheremainingwater)；

ifontheotherhanditdoesnot，andfurtherextractionisalwayspossible，therewillbeaninfinitemultitudeoffiniteequalparticlesinafinitequantity-whichisimpossible。Anotherproofmaybeadded:Sinceeverybodymustdiminishinsizewhensomethingistakenfromit，andfleshisquantitativelydefiniteinrespectbothofgreatnessandsmallness，itisclearthatfromtheminimumquantityoffleshnobodycanbeseparatedout；forthefleshleftwouldbelessthantheminimumofflesh。

Lastly(4)ineachofhisinfinitebodiestherewouldbealreadypresentinfinitefleshandbloodandbrain-havingadistinctexistence，however，fromoneanother，andnolessrealthantheinfinitebodies，andeachinfinite:whichiscontrarytoreason。

Thestatementthatcompleteseparationneverwilltakeplaceiscorrectenough，thoughAnaxagorasisnotfullyawareofwhatitmeans。

Foraffectionsareindeedinseparable。Ifthencoloursandstateshadenteredintothemixture，andifseparationtookplace，therewouldbea"white"ora"healthy"whichwasnothingbutwhiteorhealthy，i。e。wasnotthepredicateofasubject。Sohis"Mind"isanabsurdpersonaimingattheimpossible，ifheissupposedtowishtoseparatethem，anditisimpossibletodoso，bothinrespectofquantityandofquality-ofquantity，becausethereisnominimummagnitude，andofquality，becauseaffectionsareinseparable。

NorisAnaxagorasrightaboutthecomingtobeofhomogeneousbodies。Itistruethereisasenseinwhichclayisdividedintopiecesofclay，butthereisanotherinwhichitisnot。Waterandairare，andaregenerated"from"eachother，butnotinthewayinwhichbrickscome"from"ahouseandagainahouse"from"bricks；

anditisbettertoassumeasmallerandfinitenumberofprinciples，asEmpedoclesdoes。

5

Allthinkersthenagreeinmakingthecontrariesprinciples，boththosewhodescribetheAllasoneandunmoved(forevenParmenidestreatshotandcoldasprinciplesunderthenamesoffireandearth)

andthosetoowhousetherareandthedense。ThesameistrueofDemocritusalso，withhisplenumandvoid，bothofwhichexist，besays，theoneasbeing，theotherasnot-being。Againhespeaksofdifferencesinposition，shape，andorder，andthesearegeneraofwhichthespeciesarecontraries，namely，ofposition，aboveandbelow，beforeandbehind；ofshape，angularandangle-less，straightandround。

Itisplainthenthattheyallinonewayoranotheridentifythecontrarieswiththeprinciples。Andwithgoodreason。Forfirstprinciplesmustnotbederivedfromoneanothernorfromanythingelse，whileeverythinghastobederivedfromthem。Buttheseconditionsarefulfilledbytheprimarycontraries，whicharenotderivedfromanythingelsebecausetheyareprimary，norfromeachotherbecausetheyarecontraries。

Butwemustseehowthiscanbearrivedatasareasonedresult，aswellasinthewayjustindicated。

Ourfirstpresuppositionmustbethatinnaturenothingactson，orisactedonby，anyotherthingatrandom，normayanythingcomefromanythingelse，unlesswemeanthatitdoessoinvirtueofaconcomitantattribute。Forhowcould"white"comefrom"musical"，unless"musical"happenedtobeanattributeofthenot-whiteoroftheblack?No，"white"comesfrom"not-white"-andnotfromany"not-white"，butfromblackorsomeintermediatecolour。Similarly，"musical"comestobefrom"not-musical"，butnotfromanythingotherthanmusical，butfrom"unmusical"oranyintermediatestatetheremaybe。

Noragaindothingspassintothefirstchancething；"white"doesnotpassinto"musical"(except，itmaybe，invirtueofaconcomitantattribute)，butinto"not-white"-andnotintoanychancethingwhichisnotwhite，butintoblackoranintermediatecolour；"musical"

passesinto"not-musical"-andnotintoanychancethingotherthanmusical，butinto"unmusical"oranyintermediatestatetheremaybe。

Thesameholdsofotherthingsalso:eventhingswhicharenotsimplebutcomplexfollowthesameprinciple，buttheoppositestatehasnotreceivedaname，sowefailtonoticethefact。Whatisintunemustcomefromwhatisnotintune，andviceversa；thetunedpassesintountunedness-andnotintoanyuntunedness，butintothecorrespondingopposite。Itdoesnotmatterwhetherwetakeattunement，order，orcompositionforourillustration；theprincipleisobviouslythesameinall，andinfactappliesequallytotheproductionofahouse，astatue，oranyothercomplex。Ahousecomesfromcertainthingsinacertainstateofseparationinsteadofconjunction，astatue(oranyotherthingthathasbeenshaped)fromshapelessness-eachoftheseobjectsbeingpartlyorderandpartlycomposition。

Ifthenthisistrue，everythingthatcomestobeorpassesawayfrom，orpassesinto，itscontraryoranintermediatestate。Buttheintermediatesarederivedfromthecontraries-colours，forinstance，fromblackandwhite。Everything，therefore，thatcomestobebyanaturalprocessiseitheracontraryoraproductofcontraries。

Uptothispointwehavepracticallyhadmostoftheotherwritersonthesubjectwithus，asIhavesaidalready:forallofthemidentifytheirelements，andwhattheycalltheirprinciples，withthecontraries，givingnoreasonindeedforthetheory，butcontrainedasitwerebythetruthitself。Theydiffer，however，fromoneanotherinthatsomeassumecontrarieswhicharemoreprimary，otherscontrarieswhicharelessso:somethosemoreknowableintheorderofexplanation，othersthosemorefamiliartosense。Forsomemakehotandcold，oragainmoistanddry，theconditionsofbecoming；whileothersmakeoddandeven，oragainLoveandStrife；andthesedifferfromeachotherinthewaymentioned。

Hencetheirprinciplesareinonesensethesame，inanotherdifferent；differentcertainly，asindeedmostpeoplethink，butthesameinasmuchastheyareanalogous；forallaretakenfromthesametableofcolumns，someofthepairsbeingwider，othersnarrowerinextent。Inthiswaythentheirtheoriesareboththesameanddifferent，somebetter，someworse；some，asIhavesaid，takeastheircontrarieswhatismoreknowableintheorderofexplanation，otherswhatismorefamiliartosense。(Theuniversalismoreknowableintheorderofexplanation，theparticularintheorderofsense:forexplanationhastodowiththeuniversal，sensewiththeparticular。)"Thegreatandthesmall"，forexample，belongtotheformerclass，"thedenseandtherare"tothelatter。

Itisclearthenthatourprinciplesmustbecontraries。

6

Thenextquestioniswhethertheprinciplesaretwoorthreeormoreinnumber。

Onetheycannotbe，fortherecannotbeonecontrary。Norcantheybeinnumerable，because，ifso，Beingwillnotbeknowable:andinanyonegenusthereisonlyonecontrariety，andsubstanceisonegenus:

alsoafinitenumberissufficient，andafinitenumber，suchastheprinciplesofEmpedocles，isbetterthananinfinitemultitude；forEmpedoclesprofessestoobtainfromhisprinciplesallthatAnaxagorasobtainsfromhisinnumerableprinciples。Lastly，somecontrariesaremoreprimarythanothers，andsomearisefromothers-forexamplesweetandbitter，whiteandblack-whereastheprinciplesmustalwaysremainprinciples。

Thiswillsufficetoshowthattheprinciplesareneitheronenorinnumerable。

Granted，then，thattheyarealimitednumber，itisplausibletosupposethemmorethantwo。Foritisdifficulttoseehoweitherdensityshouldbeofsuchanatureastoactinanywayonrarityorrarityondensity。Thesameistrueofanyotherpairofcontraries；

forLovedoesnotgatherStrifetogetherandmakethingsoutofit，nordoesStrifemakeanythingoutofLove，butbothactonathirdthingdifferentfromboth。Someindeedassumemorethanonesuchthingfromwhichtheyconstructtheworldofnature。

Otherobjectionstotheviewthatitisnotnecessarytoassumeathirdprincipleasasubstratummaybeadded。(1)Wedonotfindthatthecontrariesconstitutethesubstanceofanything。Butwhatisafirstprincipleoughtnottobethepredicateofanysubject。Ifitwere，therewouldbeaprincipleofthesupposedprinciple:forthesubjectisaprinciple，andpriorpresumablytowhatispredicatedofit。Again(2)weholdthatasubstanceisnotcontrarytoanothersubstance。Howthencansubstancebederivedfromwhatarenotsubstances?Orhowcannon-substancesbepriortosubstance?

Ifthenweacceptboththeformerargumentandthisone，wemust，topreserveboth，assumeathirdsomewhatasthesubstratumofthecontraries，suchasisspokenofbythosewhodescribetheAllasonenature-waterorfireorwhatisintermediatebetweenthem。Whatisintermediateseemspreferable；forfire，earth，air，andwaterarealreadyinvolvedwithpairsofcontraries。Thereis，therefore，muchtobesaidforthosewhomaketheunderlyingsubstancedifferentfromthesefour；oftherest，thenextbestchoiceisair，aspresentingsensibledifferencesinalessdegreethantheothers；

andafterair，water。All，however，agreeinthis，thattheydifferentiatetheirOnebymeansofthecontraries，suchasdensityandrarityandmoreandless，whichmayofcoursebegeneralized，ashasalreadybeensaidintoexcessanddefect。Indeedthisdoctrinetoo(thattheOneandexcessanddefectaretheprinciplesofthings)

wouldappeartobeofoldstanding，thoughindifferentforms；fortheearlythinkersmadethetwotheactiveandtheonethepassiveprinciple，whereassomeofthemorerecentmaintainthereverse。

Tosupposethenthattheelementsarethreeinnumberwouldseem，fromtheseandsimilarconsiderations，aplausibleview，asIsaidbefore。Ontheotherhand，theviewthattheyaremorethanthreeinnumberwouldseemtobeuntenable。

Fortheonesubstratumissufficienttobeactedon；butifwehavefourcontraries，therewillbetwocontrarieties，andweshallhavetosupposeanintermediatenatureforeachpairseparately。If，ontheotherhand，thecontrarieties，beingtwo，cangeneratefromeachother，thesecondcontrarietywillbesuperfluous。Moreover，itisimpossiblethatthereshouldbemorethanoneprimarycontrariety。Forsubstanceisasinglegenusofbeing，sothattheprinciplescandifferonlyaspriorandposterior，notingenus；inasinglegenusthereisalwaysasinglecontrariety，alltheothercontrarietiesinitbeingheldtobereducibletoone。

Itisclearthenthatthenumberofelementsisneitheronenormorethantwoorthree；butwhethertwoorthreeis，asIsaid，aquestionofconsiderabledifficulty。

7

Wewillnowgiveourownaccount，approachingthequestionfirstwithreferencetobecominginitswidestsense:forweshallbefollowingthenaturalorderofinquiryifwespeakfirstofcommoncharacteristics，andtheninvestigatethecharacteristicsofspecialcases。

Wesaythatonethingcomestobefromanotherthing，andonesortofthingfromanothersortofthing，bothinthecaseofsimpleandofcomplexthings。Imeanthefollowing。Wecansay(1)"manbecomesmusical"，(2)whatis"not-musicalbecomesmusical"，or(3)，the"not-musicalmanbecomesamusicalman"。Nowwhatbecomesin(1)and(2)-"man"and"notmusical"-Icallsimple，andwhateachbecomes-"musical"-simplealso。Butwhen(3)wesaythe"not-musicalmanbecomesamusicalman"，bothwhatbecomesandwhatitbecomesarecomplex。

Asregardsoneofthesesimple"thingsthatbecome"wesaynotonly"thisbecomesso-and-so"，butalso"frombeingthis，comestobeso-and-so"，as"frombeingnot-musicalcomestobemusical"；asregardstheotherwedonotsaythisinallcases，aswedonotsay(1)"frombeingamanhecametobemusical"butonly"themanbecamemusical"。

Whena"simple"thingissaidtobecomesomething，inonecase(1)

itsurvivesthroughtheprocess，intheother(2)itdoesnot。Formanremainsamanandissuchevenwhenhebecomesmusical，whereaswhatisnotmusicalorisunmusicaldoesnotcontinuetoexist，eithersimplyorcombinedwiththesubject。

Thesedistinctionsdrawn，onecangatherfromsurveyingthevariouscasesofbecominginthewaywearedescribingthat，aswesay，theremustalwaysbeanunderlyingsomething，namelythatwhichbecomes，andthatthis，thoughalwaysonenumerically，informatleastisnotone。(BythatImeanthatitcanbedescribedindifferentways。)For"tobeman"isnotthesameas"tobeunmusical"。

Onepartsurvives，theotherdoesnot:whatisnotanoppositesurvives(for"man"survives)，but"not-musical"or"unmusical"doesnotsurvive，nordoesthecompoundofthetwo，namely"unmusicalman"。

Wespeakof"becomingthatfromthis"insteadof"thisbecomingthat"moreinthecaseofwhatdoesnotsurvivethechange-"becomingmusicalfromunmusical"，not"fromman"-butthereareexceptions，aswesometimesusethelatterformofexpressionevenofwhatsurvives；wespeakof"astatuecomingtobefrombronze"，notofthe"bronzebecomingastatue"。Thechange，however，fromanoppositewhichdoesnotsurviveisdescribedindifferentlyinbothways，"becomingthatfromthis"or"thisbecomingthat"。Wesayboththat"theunmusicalbecomesmusical"，andthat"fromunmusicalhebecomesmusical"。Andsobothformsareusedofthecomplex，"becomingamusicalmanfromanunmusicalman"，andunmusicalmanbecomingamusicalman"。

Buttherearedifferentsensesof"comingtobe"。Insomecaseswedonotusetheexpression"cometobe"，but"cometobeso-and-so"。

Onlysubstancesaresaidto"cometobe"intheunqualifiedsense。

Nowinallcasesotherthansubstanceitisplainthattheremustbesomesubject，namely，thatwhichbecomes。Forweknowthatwhenathingcomestobeofsuchaquantityorqualityorinsucharelation，time，orplace，asubjectisalwayspresupposed，sincesubstancealoneisnotpredicatedofanothersubject，buteverythingelseofsubstance。

Butthatsubstancestoo，andanythingelsethatcanbesaid"tobe"withoutqualification，cometobefromsomesubstratum，willappearonexamination。Forwefindineverycasesomethingthatunderliesfromwhichproceedsthatwhichcomestobe；forinstance，animalsandplantsfromseed。

Generallythingswhichcometobe，cometobeindifferentways:(1)

bychangeofshape，asastatue；(2)byaddition，asthingswhichgrow；(3)bytakingaway，astheHermesfromthestone；(4)byputtingtogether，asahouse；(5)byalteration，asthingswhich"turn"inrespectoftheirmaterialsubstance。

Itisplainthattheseareallcasesofcomingtobefromasubstratum。

Thus，clearly，fromwhathasbeensaid，whatevercomestobeisalwayscomplex。Thereis，ontheonehand，(a)somethingwhichcomesintoexistence，andagain(b)somethingwhichbecomesthat-thelatter(b)intwosenses，eitherthesubjectortheopposite。Bythe"opposite"Imeanthe"unmusical"，bythe"subject""man"，andsimilarlyIcalltheabsenceofshapeorformororderthe"opposite"，andthebronzeorstoneorgoldthe"subject"。

Plainlythen，ifthereareconditionsandprincipleswhichconstitutenaturalobjectsandfromwhichtheyprimarilyareorhavecometobe-havecometobe，Imean，whateachissaidtobeinitsessentialnature，notwhateachisinrespectofaconcomitantattribute-plainly，Isay，everythingcomestobefrombothsubjectandform。For"musicalman"iscomposed(inaway)of"man"and"musical":

youcananalyseitintothedefinitionsofitselements。Itisclearthenthatwhatcomestobewillcometobefromtheseelements。

Nowthesubjectisonenumerically，thoughitistwoinform。(Foritistheman，thegold-the"matter"generally-thatiscounted，foritismoreofthenatureofa"this"，andwhatcomestobedoesnotcomefromitinvirtueofaconcomitantattribute；theprivation，ontheotherhand，andthecontraryareincidentalintheprocess。)Andthepositiveformisone-theorder，theacquiredartofmusic，oranysimilarpredicate。

Thereisasense，therefore，inwhichwemustdeclaretheprinciplestobetwo，andasenseinwhichtheyarethree；asenseinwhichthecontrariesaretheprinciples-sayforexamplethemusicalandtheunmusical，thehotandthecold，thetunedandtheuntuned-andasenseinwhichtheyarenot，sinceitisimpossibleforthecontrariestobeactedonbyeachother。Butthisdifficultyalsoissolvedbythefactthatthesubstratumisdifferentfromthecontraries，foritisitselfnotacontrary。Theprinciplesthereforeare，inaway，notmoreinnumberthanthecontraries，butasitweretwo，noryetpreciselytwo，sincethereisadifferenceofessentialnature，butthree。For"tobeman"isdifferentfrom"tobeunmusical"，and"tobeunformed"from"tobebronze"。

Wehavenowstatedthenumberoftheprinciplesofnaturalobjectswhicharesubjecttogeneration，andhowthenumberisreached:anditisclearthattheremustbeasubstratumforthecontraries，andthatthecontrariesmustbetwo。(Yetinanotherwayofputtingitthisisnotnecessary，asoneofthecontrarieswillservetoeffectthechangebyitssuccessiveabsenceandpresence。)

Theunderlyingnatureisanobjectofscientificknowledge，byananalogy。Forasthebronzeistothestatue，thewoodtothebed，orthematterandtheformlessbeforereceivingformtoanythingwhichhasform，soistheunderlyingnaturetosubstance，i。e。the"this"orexistent。

Thisthenisoneprinciple(thoughnotoneorexistentinthesamesenseasthe"this")，andthedefinitionwasoneasweagreed；thenfurtherthereisitscontrary，theprivation。Inwhatsensethesearetwo，andinwhatsensemore，hasbeenstatedabove。Briefly，weexplainedfirstthatonlythecontrarieswereprinciples，andlaterthatasubstratumwasindispensable，andthattheprincipleswerethree；ourlaststatementhaselucidatedthedifferencebetweenthecontraries，themutualrelationoftheprinciples，andthenatureofthesubstratum。Whethertheformorthesubstratumistheessentialnatureofaphysicalobjectisnotyetclear。Butthattheprinciplesarethree，andinwhatsense，andthewayinwhicheachisaprinciple，isclear。

Somuchthenforthequestionofthenumberandthenatureoftheprinciples。

8

Wewillnowproceedtoshowthatthedifficultyoftheearlythinkers，aswellasourown，issolvedinthiswayalone。

Thefirstofthosewhostudiedscienceweremisledintheirsearchfortruthandthenatureofthingsbytheirinexperience，whichasitwerethrustthemintoanotherpath。Sotheysaythatnoneofthethingsthatareeithercomestobeorpassesoutofexistence，becausewhatcomestobemustdosoeitherfromwhatisorfromwhatisnot，bothofwhichareimpossible。Forwhatiscannotcometobe(becauseitisalready)，andfromwhatisnotnothingcouldhavecometobe(becausesomethingmustbepresentasasubstratum)。Sotootheyexaggeratedtheconsequenceofthis，andwentsofarastodenyeventheexistenceofapluralityofthings，maintainingthatonlyBeingitselfis。Suchthenwastheiropinion，andsuchthereasonforitsadoption。

Ourexplanationontheotherhandisthatthephrases"somethingcomestobefromwhatisorfromwhatisnot"，"whatisnotorwhatisdoessomethingorhassomethingdonetoitorbecomessomeparticularthing"，aretobetaken(inthefirstwayofputtingourexplanation)inthesamesenseas"adoctordoessomethingorhassomethingdonetohim"，"isorbecomessomethingfrombeingadoctor。"

Theseexpressionsmaybetakenintwosenses，andsotoo，clearly，may"frombeing"，and"beingactsorisactedon"。Adoctorbuildsahouse，notquadoctor，butquahousebuilder，andturnsgray，notquadoctor，butquadark-haired。Ontheotherhandhedoctorsorfailstodoctorquadoctor。Butweareusingwordsmostappropriatelywhenwesaythatadoctordoessomethingorundergoessomething，orbecomessomethingfrombeingadoctor，ifhedoes，undergoes，orbecomesquadoctor。Clearlythenalso"tocometobeso-and-sofromnot-being"

means"quanot-being"。

Itwasthroughfailuretomakethisdistinctionthatthosethinkersgavethematterup，andthroughthiserrorthattheywentsomuchfartherastrayastosupposethatnothingelsecomestobeorexistsapartfromBeingitself，thusdoingawaywithallbecoming。

Weourselvesareinagreementwiththeminholdingthatnothingcanbesaidwithoutqualificationtocomefromwhatisnot。Butneverthelesswemaintainthatathingmay"cometobefromwhatisnot"-thatis，inaqualifiedsense。Forathingcomestobefromtheprivation，whichinitsownnatureisnot-being，-thisnotsurvivingasaconstituentoftheresult。Yetthiscausessurprise，anditisthoughtimpossiblethatsomethingshouldcometobeinthewaydescribedfromwhatisnot。

Inthesamewaywemaintainthatnothingcomestobefrombeing，andthatbeingdoesnotcometobeexceptinaqualifiedsense。Inthatway，however，itdoes，justasanimalmightcometobefromanimal，andananimalofacertainkindfromananimalofacertainkind。

Thus，supposeadogtocometobefromahorse。Thedogwouldthen，itistrue，cometobefromanimal(aswellasfromananimalofacertainkind)butnotasanimal，forthatisalreadythere。Butifanythingistobecomeananimal，notinaqualifiedsense，itwillnotbefromanimal:andifbeing，notfrombeing-norfromnot-beingeither，forithasbeenexplainedthatby"fromnotbeing"wemeanfromnot-beingquanot-being。

Notefurtherthatwedonotsubverttheprinciplethateverythingeitherisorisnot。

Thisthenisonewayofsolvingthedifficulty。Anotherconsistsinpointingoutthatthesamethingscanbeexplainedintermsofpotentialityandactuality。Butthishasbeendonewithgreaterprecisionelsewhere。So，aswesaid，thedifficultieswhichconstrainpeopletodenytheexistenceofsomeofthethingswementionedarenowsolved。Foritwasthisreasonwhichalsocausedsomeoftheearlierthinkerstoturnsofarasidefromtheroadwhichleadstocomingtobeandpassingawayandchangegenerally。

Iftheyhadcomeinsightofthisnature，alltheirignorancewouldhavebeendispelled。

9

Others，indeed，haveapprehendedthenatureinquestion，butnotadequately。

Inthefirstplacetheyallowthatathingmaycometobewithoutqualificationfromnotbeing，acceptingonthispointthestatementofParmenides。Secondly，theythinkthatifthesubstratumisonenumerically，itmusthavealsoonlyasinglepotentiality-whichisaverydifferentthing。

Nowwedistinguishmatterandprivation，andholdthatoneofthese，namelythematter，isnot-beingonlyinvirtueofanattributewhichithas，whiletheprivationinitsownnatureisnot-being；andthatthematterisnearly，inasenseis，substance，whiletheprivationinnosenseis。They，ontheotherhand，identifytheirGreatandSmallalikewithnotbeing，andthatwhethertheyaretakentogetherasoneorseparately。Theirtriadisthereforeofquiteadifferentkindfromours。Fortheygotsofarastoseethattheremustbesomeunderlyingnature，buttheymakeitone-forevenifonephilosophermakesadyadofit，whichhecallsGreatandSmall，theeffectisthesame，forheoverlookedtheothernature。Fortheonewhichpersistsisajointcause，withtheform，ofwhatcomestobe-amother，asitwere。Butthenegativepartofthecontrarietymayoftenseem，ifyouconcentrateyourattentiononitasanevilagent，nottoexistatall。

Foradmittingwiththemthatthereissomethingdivine，good，anddesirable，weholdthattherearetwootherprinciples，theonecontrarytoit，theothersuchasofitsownnaturetodesireandyearnforit。Buttheconsequenceoftheirviewisthatthecontrarydesiresitswtextinction。Yettheformcannotdesireitself，foritisnotdefective；norcanthecontrarydesireit，forcontrariesaremutuallydestructive。Thetruthisthatwhatdesirestheformismatter，asthefemaledesiresthemaleandtheuglythebeautiful-onlytheuglyorthefemalenotpersebutperaccidens。

Themattercomestobeandceasestobeinonesense，whileinanotheritdoesnot。Asthatwhichcontainstheprivation，itceasestobeinitsownnature，forwhatceasestobe-theprivation-iscontainedwithinit。Butaspotentialityitdoesnotceasetobeinitsownnature，butisnecessarilyoutsidethesphereofbecomingandceasingtobe。Forifitcametobe，somethingmusthaveexistedasaprimarysubstratumfromwhichitshouldcomeandwhichshouldpersistinit；butthisisitsownspecialnature，sothatitwillbebeforecomingtobe。(Formydefinitionofmatterisjustthis-theprimarysubstratumofeachthing，fromwhichitcomestobewithoutqualification，andwhichpersistsintheresult。)Andifitceasestobeitwillpassintothatatthelast，soitwillhaveceasedtobebeforeceasingtobe。

Theaccuratedeterminationofthefirstprincipleinrespectofform，whetheritisoneormanyandwhatitisorwhattheyare，istheprovinceoftheprimarytypeofscience；sothesequestionsmaystandovertillthen。Butofthenatural，i。e。perishable，formsweshallspeakintheexpositionswhichfollow。

Theabove，then，maybetakenassufficienttoestablishthatthereareprinciplesandwhattheyareandhowmanythereare。Nowletusmakeafreshstartandproceed。

BookII

1

Ofthingsthatexist，someexistbynature，somefromothercauses。

"Bynature"theanimalsandtheirpartsexist，andtheplantsandthesimplebodies(earth，fire，air，water)-forwesaythattheseandthelikeexist"bynature"。

Allthethingsmentionedpresentafeatureinwhichtheydifferfromthingswhicharenotconstitutedbynature。Eachofthemhaswithinitselfaprincipleofmotionandofstationariness(inrespectofplace，orofgrowthanddecrease，orbywayofalteration)。Ontheotherhand，abedandacoatandanythingelseofthatsort，quareceivingthesedesignationsi。e。insofarastheyareproductsofart-havenoinnateimpulsetochange。Butinsofarastheyhappentobecomposedofstoneorofearthorofamixtureofthetwo，theydohavesuchanimpulse，andjusttothatextentwhichseemstoindicatethatnatureisasourceorcauseofbeingmovedandofbeingatrestinthattowhichitbelongsprimarily，invirtueofitselfandnotinvirtueofaconcomitantattribute。

Isay"notinvirtueofaconcomitantattribute"，because(forinstance)amanwhoisadoctormightcurehimself。Neverthelessitisnotinsofarasheisapatientthathepossessestheartofmedicine:itmerelyhashappenedthatthesamemanisdoctorandpatient-andthatiswhytheseattributesarenotalwaysfoundtogether。Soitiswithallotherartificialproducts。Noneofthemhasinitselfthesourceofitsownproduction。Butwhileinsomecases(forinstancehousesandtheotherproductsofmanuallabour)

thatprincipleisinsomethingelseexternaltothething，inothersthosewhichmaycauseachangeinthemselvesinvirtueofaconcomitantattribute-itliesinthethingsthemselves(butnotinvirtueofwhattheyare)。

"Nature"theniswhathasbeenstated。Things"haveanature"whichhaveaprincipleofthiskind。Eachofthemisasubstance；foritisasubject，andnaturealwaysimpliesasubjectinwhichitinheres。

Theterm"accordingtonature"isappliedtoallthesethingsandalsototheattributeswhichbelongtotheminvirtueofwhattheyare，forinstancethepropertyoffiretobecarriedupwards-whichisnota"nature"nor"hasanature"butis"bynature"or"accordingtonature"。

Whatnatureis，then，andthemeaningoftheterms"bynature"and"accordingtonature"，hasbeenstated。Thatnatureexists，itwouldbeabsurdtotrytoprove；foritisobviousthattherearemanythingsofthiskind，andtoprovewhatisobviousbywhatisnotisthemarkofamanwhoisunabletodistinguishwhatisself-evidentfromwhatisnot。(Thisstateofmindisclearlypossible。Amanblindfrombirthmightreasonaboutcolours。Presumablythereforesuchpersonsmustbetalkingaboutwordswithoutanythoughttocorrespond。)

Someidentifythenatureorsubstanceofanaturalobjectwiththatimmediateconstituentofitwhichtakenbyitselfiswithoutarrangement，e。g。thewoodisthe"nature"ofthebed，andthebronzethe"nature"ofthestatue。

AsanindicationofthisAntiphonpointsoutthatifyouplantedabedandtherottingwoodacquiredthepowerofsendingupashoot，itwouldnotbeabedthatwouldcomeup，butwood-whichshowsthatthearrangementinaccordancewiththerulesoftheartismerelyanincidentalattribute，whereastherealnatureistheother，which，further，persistscontinuouslythroughtheprocessofmaking。

Butifthematerialofeachoftheseobjectshasitselfthesamerelationtosomethingelse，saybronze(orgold)towater，bones(orwood)toearthandsoon，that(theysay)wouldbetheirnatureandessence。Consequentlysomeassertearth，othersfireorairorwaterorsomeorallofthese，tobethenatureofthethingsthatare。

Forwhateveranyoneofthemsupposedtohavethischaracter-whetheronethingormorethanonething-thisorthesehedeclaredtobethewholeofsubstance，allelsebeingitsaffections，states，ordispositions。Everysuchthingtheyheldtobeeternal(foritcouldnotpassintoanythingelse)，butotherthingstocomeintobeingandceasetobetimeswithoutnumber。

Thisthenisoneaccountof"nature"，namelythatitistheimmediatematerialsubstratumofthingswhichhaveinthemselvesaprincipleofmotionorchange。

Anotheraccountisthat"nature"istheshapeorformwhichisspecifiedinthedefinitionofthething。

Fortheword"nature"isappliedtowhatisaccordingtonatureandthenaturalinthesamewayas"art"isappliedtowhatisartisticoraworkofart。Weshouldnotsayinthelattercasethatthereisanythingartisticaboutathing，ifitisabedonlypotentially，notyethavingtheformofabed；norshouldwecallitaworkofart。Thesameistrueofnaturalcompounds。Whatispotentiallyfleshorbonehasnotyetitsown"nature"，anddoesnotexistuntilitreceivestheformspecifiedinthedefinition，whichwenameindefiningwhatfleshorboneis。Thusinthesecondsenseof"nature"itwouldbetheshapeorform(notseparableexceptinstatement)ofthingswhichhaveinthemselvesasourceofmotion。(Thecombinationofthetwo，e。g。man，isnot"nature"but"bynature"or"natural"。)

Theformindeedis"nature"ratherthanthematter；forathingismoreproperlysaidtobewhatitiswhenithasattainedtofulfilmentthanwhenitexistspotentially。Againmanisbornfromman，butnotbedfrombed。Thatiswhypeoplesaythatthefigureisnotthenatureofabed，butthewoodis-ifthebedsproutednotabedbutwoodwouldcomeup。Butevenifthefigureisart，thenonthesameprincipletheshapeofmanishisnature。Formanisbornfromman。

Wealsospeakofathing"snatureasbeingexhibitedintheprocessofgrowthbywhichitsnatureisattained。The"nature"inthissenseisnotlike"doctoring"，whichleadsnottotheartofdoctoringbuttohealth。Doctoringmuststartfromtheart，notleadtoit。Butitisnotinthiswaythatnature(intheonesense)isrelatedtonature(intheother)。Whatgrowsquagrowinggrowsfromsomethingintosomething。Intowhatthendoesitgrow?Notintothatfromwhichitarosebutintothattowhichittends。Theshapethenisnature。

"Shape"and"nature"，itshouldbeadded，areintwosenses。Fortheprivationtooisinawayform。Butwhetherinunqualifiedcomingtobethereisprivation，i。e。acontrarytowhatcomestobe，wemustconsiderlater。

2

Wehavedistinguished，then，thedifferentwaysinwhichtheterm"nature"isused。

Thenextpointtoconsiderishowthemathematiciandiffersfromthephysicist。Obviouslyphysicalbodiescontainsurfacesandvolumes，linesandpoints，andthesearethesubject-matterofmathematics。

Further，isastronomydifferentfromphysicsoradepartmentofit?Itseemsabsurdthatthephysicistshouldbesupposedtoknowthenatureofsunormoon，butnottoknowanyoftheiressentialattributes，particularlyasthewritersonphysicsobviouslydodiscusstheirshapealsoandwhethertheearthandtheworldaresphericalornot。

Nowthemathematician，thoughhetootreatsofthesethings，neverthelessdoesnottreatofthemasthelimitsofaphysicalbody；nordoesheconsidertheattributesindicatedastheattributesofsuchbodies。Thatiswhyheseparatesthem；forinthoughttheyareseparablefrommotion，anditmakesnodifference，nordoesanyfalsityresult，iftheyareseparated。TheholdersofthetheoryofFormsdothesame，thoughtheyarenotawareofit；fortheyseparatetheobjectsofphysics，whicharelessseparablethanthoseofmathematics。Thisbecomesplainifonetriestostateineachofthetwocasesthedefinitionsofthethingsandoftheirattributes。

"Odd"and"even"，"straight"and"curved"，andlikewise"number"，"line"，and"figure"，donotinvolvemotion；notso"flesh"and"bone"

and"man"-thesearedefinedlike"snubnose"，notlike"curved"。

Similarevidenceissuppliedbythemorephysicalofthebranchesofmathematics，suchasoptics，harmonics，andastronomy。Theseareinawaytheconverseofgeometry。Whilegeometryinvestigatesphysicallinesbutnotquaphysical，opticsinvestigatesmathematicallines，butquaphysical，notquamathematical。

Since"nature"hastwosenses，theformandthematter，wemustinvestigateitsobjectsaswewouldtheessenceofsnubness。Thatis，suchthingsareneitherindependentofmatternorcanbedefinedintermsofmatteronly。Heretooindeedonemightraiseadifficulty。

Sincetherearetwonatures，withwhichisthephysicistconcerned?Orshouldheinvestigatethecombinationofthetwo?Butifthecombinationofthetwo，thenalsoeachseverally。Doesitbelongthentothesameortodifferentsciencestoknoweachseverally?

Ifwelookattheancients，physicswouldtobeconcernedwiththematter。(ItwasonlyveryslightlythatEmpedoclesandDemocritustouchedontheformsandtheessence。)

Butifontheotherhandartimitatesnature，anditisthepartofthesamedisciplinetoknowtheformandthematteruptoapoint(e。g。thedoctorhasaknowledgeofhealthandalsoofbileandphlegm，inwhichhealthisrealized，andthebuilderbothoftheformofthehouseandofthematter，namelythatitisbricksandbeams，andsoforth):ifthisisso，itwouldbethepartofphysicsalsotoknownatureinbothitssenses。

Again，"thatforthesakeofwhich"，ortheend，belongstothesamedepartmentofknowledgeasthemeans。Butthenatureistheendor"thatforthesakeofwhich"。Forifathingundergoesacontinuouschangeandthereisastagewhichislast，thisstageistheendor"thatforthesakeofwhich"。(Thatiswhythepoetwascarriedawayintomakinganabsurdstatementwhenhesaid"hehastheendforthesakeofwhichhewasborn"。Fornoteverystagethatislastclaimstobeanend，butonlythatwhichisbest。)

Fortheartsmaketheirmaterial(somesimply"make"it，othersmakeitserviceable)，andweuseeverythingasifitwasthereforoursake。(Wealsoareinasenseanend。"Thatforthesakeofwhich"hastwosenses:thedistinctionismadeinourworkOnPhilosophy。)Thearts，therefore，whichgovernthematterandhaveknowledgearetwo，namelytheartwhichusestheproductandtheartwhichdirectstheproductionofit。Thatiswhytheusingartalsoisinasensedirective；butitdiffersinthatitknowstheform，whereastheartwhichisdirectiveasbeingconcernedwithproductionknowsthematter。Forthehelmsmanknowsandprescribeswhatsortofformahelmshouldhave，theotherfromwhatwooditshouldbemadeandbymeansofwhatoperations。Intheproductsofart，however，wemakethematerialwithaviewtothefunction，whereasintheproductsofnaturethematteristhereallalong。

Again，matterisarelativeterm:toeachformtherecorrespondsaspecialmatter。Howfarthenmustthephysicistknowtheformoressence?Uptoapoint，perhaps，asthedoctormustknowsineworthesmithbronze(i。e。untilheunderstandsthepurposeofeach):

andthephysicistisconcernedonlywiththingswhoseformsareseparableindeed，butdonotexistapartfrommatter。Manisbegottenbymanandbythesunaswell。Themodeofexistenceandessenceoftheseparableitisthebusinessoftheprimarytypeofphilosophytodefine。

3

Nowthatwehaveestablishedthesedistinctions，wemustproceedtoconsidercauses，theircharacterandnumber。Knowledgeistheobjectofourinquiry，andmendonotthinktheyknowathingtilltheyhavegraspedthe"why"of(whichistograspitsprimarycause)。Soclearlywetoomustdothisasregardsbothcomingtobeandpassingawayandeverykindofphysicalchange，inorderthat，knowingtheirprinciples，wemaytrytorefertotheseprincipleseachofourproblems。

Inonesense，then，(1)thatoutofwhichathingcomestobeandwhichpersists，iscalled"cause"，e。g。thebronzeofthestatue，thesilverofthebowl，andthegeneraofwhichthebronzeandthesilverarespecies。

Inanothersense(2)theformorthearchetype，i。e。thestatementoftheessence，anditsgenera，arecalled"causes"(e。g。oftheoctavetherelationof2:1，andgenerallynumber)，andthepartsinthedefinition。

Again(3)theprimarysourceofthechangeorcomingtorest；e。g。

themanwhogaveadviceisacause，thefatheriscauseofthechild，andgenerallywhatmakesofwhatismadeandwhatcauseschangeofwhatischanged。

Again(4)inthesenseofendor"thatforthesakeofwhich"athingisdone，e。g。healthisthecauseofwalkingabout。("Whyishewalkingabout?"wesay。"Tobehealthy"，and，havingsaidthat，wethinkwehaveassignedthecause。)Thesameistruealsoofalltheintermediatestepswhicharebroughtaboutthroughtheactionofsomethingelseasmeanstowardstheend，e。g。reductionofflesh，purging，drugs，orsurgicalinstrumentsaremeanstowardshealth。

Allthesethingsare"forthesakeof"theend，thoughtheydifferfromoneanotherinthatsomeareactivities，othersinstruments。

Thisthenperhapsexhauststhenumberofwaysinwhichtheterm"cause"isused。

Asthewordhasseveralsenses，itfollowsthatthereareseveralcausesofthesamethingnotmerelyinvirtueofaconcomitantattribute)，e。g。boththeartofthesculptorandthebronzearecausesofthestatue。Thesearecausesofthestatuequastatue，notinvirtueofanythingelsethatitmaybe-onlynotinthesameway，theonebeingthematerialcause，theotherthecausewhencethemotioncomes。Somethingscauseeachotherreciprocally，e。g。hardworkcausesfitnessandviceversa，butagainnotinthesameway，buttheoneasend，theotherastheoriginofchange。Furtherthesamethingisthecauseofcontraryresults。Forthatwhichbyitspresencebringsaboutoneresultissometimesblamedforbringingaboutthecontrarybyitsabsence。Thusweascribethewreckofashiptotheabsenceofthepilotwhosepresencewasthecauseofitssafety。

Allthecausesnowmentionedfallintofourfamiliardivisions。

Thelettersarethecausesofsyllables，thematerialofartificialproducts，fire，&c。，ofbodies，thepartsofthewhole，andthepremissesoftheconclusion，inthesenseof"thatfromwhich"。Ofthesepairstheonesetarecausesinthesenseofsubstratum，e。g。

theparts，theothersetinthesenseofessence-thewholeandthecombinationandtheform。Buttheseedandthedoctorandtheadviser，andgenerallythemaker，areallsourceswhencethechangeorstationarinessoriginates，whiletheothersarecausesinthesenseoftheendorthegoodoftherest；for"thatforthesakeofwhich"

meanswhatisbestandtheendofthethingsthatleaduptoit。

(Whetherwesaythe"gooditselforthe"apparentgood"makesnodifference。)

Suchthenisthenumberandnatureofthekindsofcause。

Nowthemodesofcausationaremany，thoughwhenbroughtunderheadstheytoocanbereducedinnumber。For"cause"isusedinmanysensesandevenwithinthesamekindonemaybepriortoanother(e。g。

thedoctorandtheexpertarecausesofhealth，therelation2:1andnumberoftheoctave)，andalwayswhatisinclusivetowhatisparticular。Anothermodeofcausationistheincidentalanditsgenera，e。g。inoneway"Polyclitus"，inanother"sculptor"isthecauseofastatue，because"beingPolyclitus"and"sculptor"areincidentallyconjoined。Alsotheclassesinwhichtheincidentalattributeisincluded；thus"aman"couldbesaidtobethecauseofastatueor，generally，"alivingcreature"。Anincidentalattributetoomaybemoreorlessremote，e。g。supposethat"apaleman"or"amusicalman"weresaidtobethecauseofthestatue。

Allcauses，bothproperandincidental，maybespokenofeitheraspotentialorasactual；e。g。thecauseofahousebeingbuiltiseither"house-builder"or"house-builderbuilding"。

Similardistinctionscanbemadeinthethingsofwhichthecausesarecauses，e。g。of"thisstatue"orof"statue"orof"image"

generally，of"thisbronze"orof"bronze"orof"material"generally。

Sotoowiththeincidentalattributes。Againwemayuseacomplexexpressionforeitherandsay，e。g。neither"Polyclitus"nor"sculptor"but"Polyclitus，sculptor"。

Allthesevarioususes，however，cometosixinnumber，undereachofwhichagaintheusageistwofold。Causemeanseitherwhatisparticularoragenus，oranincidentalattributeoragenusofthat，andtheseeitherasacomplexoreachbyitself；andallsixeitherasactualoraspotential。Thedifferenceisthismuch，thatcauseswhichareactuallyatworkandparticularexistandceasetoexistsimultaneouslywiththeireffect，e。g。thishealingpersonwiththisbeing-healedpersonandthathouse-buildingmanwiththatbeing-builthouse；butthisisnotalwaystrueofpotentialcauses——thehouseandthehousebuilderdonotpassawaysimultaneously。

Ininvestigatingthecauseofeachthingitisalwaysnecessarytoseekwhatismostprecise(asalsoinotherthings):thusmanbuildsbecauseheisabuilder，andabuilderbuildsinvirtueofhisartofbuilding。Thislastcausethenisprior:andsogenerally。

Further，genericeffectsshouldbeassignedtogenericcauses，particulareffectstoparticularcauses，e。g。statuetosculptor，thisstatuetothissculptor；andpowersarerelativetopossibleeffects，actuallyoperatingcausestothingswhichareactuallybeingeffected。

Thismustsufficeforouraccountofthenumberofcausesandthemodesofcausation。

4

Butchancealsoandspontaneityarereckonedamongcauses:manythingsaresaidbothtobeandtocometobeasaresultofchanceandspontaneity。Wemustinquirethereforeinwhatmannerchanceandspontaneityarepresentamongthecausesenumerated，andwhethertheyarethesameordifferent，andgenerallywhatchanceandspontaneityare。

Somepeopleevenquestionwhethertheyarerealornot。Theysaythatnothinghappensbychance，butthateverythingwhichweascribetochanceorspontaneityhassomedefinitecause，e。g。coming"bychance"intothemarketandfindingthereamanwhomonewantedbutdidnotexpecttomeetisduetoone"swishtogoandbuyinthemarket。Similarlyinothercasesofchanceitisalwayspossible，theymaintain，tofindsomethingwhichisthecause；butnotchance，forifchancewerereal，itwouldseemstrangeindeed，andthequestionmightberaised，whyonearthnoneofthewisemenofoldinspeakingofthecausesofgenerationanddecaytookaccountofchance；whenceitwouldseemthattheytoodidnotbelievethatanythingisbychance。Butthereisafurthercircumstancethatissurprising。Manythingsbothcometobeandarebychanceandspontaneity，andalthoughknowthateachofthemcanbeascribedtosomecause(astheoldargumentsaidwhichdeniedchance)，neverthelesstheyspeakofsomeofthesethingsashappeningbychanceandothersnot。Forthisreasonalsotheyoughttohaveatleastreferredtothematterinsomewayorother。

Certainlytheearlyphysicistsfoundnoplaceforchanceamongthecauseswhichtheyrecognized-love，strife，mind，fire，orthelike。

Thisisstrange，whethertheysupposedthatthereisnosuchthingaschanceorwhethertheythoughtthereisbutomittedtomentionit-andthattoowhentheysometimesusedit，asEmpedoclesdoeswhenhesaysthattheairisnotalwaysseparatedintothehighestregion，but"asitmaychance"。Atanyratehesaysinhiscosmogonythat"ithappenedtorunthatwayatthattime，butitoftenranotherwise。"Hetellsusalsothatmostofthepartsofanimalscametobebychance。

Therearesometoowhoascribethisheavenlysphereandalltheworldstospontaneity。Theysaythatthevortexarosespontaneously，i。e。themotionthatseparatedandarrangedinitspresentorderallthatexists。Thisstatementmightwellcausesurprise。Fortheyareassertingthatchanceisnotresponsiblefortheexistenceorgenerationofanimalsandplants，natureormindorsomethingofthekindbeingthecauseofthem(foritisnotanychancethingthatcomesfromagivenseedbutanolivefromonekindandamanfromanother)；andyetatthesametimetheyassertthattheheavenlysphereandthedivinestofvisiblethingsarosespontaneously，havingnosuchcauseasisassignedtoanimalsandplants。Yetifthisisso，itisafactwhichdeservestobedweltupon，andsomethingmightwellhavebeensaidaboutit。Forbesidestheotherabsurditiesofthestatement，itisthemoreabsurdthatpeopleshouldmakeitwhentheyseenothingcomingtobespontaneouslyintheheavens，butmuchhappeningbychanceamongthethingswhichastheysayarenotduetochance；whereasweshouldhaveexpectedexactlytheopposite。

Otherstherearewho，indeed，believethatchanceisacause，butthatitisinscrutabletohumanintelligence，asbeingadivinethingandfullofmystery。

Thuswemustinquirewhatchanceandspontaneityare，whethertheyarethesameordifferent，andhowtheyfitintoourdivisionofcauses。