第7章

(1)Firstthenwithregardtowhatwementionedfirst，doesit

belongtooneortomoresciencestoinvestigateallthekindsof

causes？Howcoulditbelongtoonesciencetorecognizetheprinciples

ifthesearenotcontrary？

Further，therearemanythingstowhichnotalltheprinciples

pertain。Forhowcanaprincipleofchangeorthenatureofthegood

existforunchangeablethings，sinceeverythingthatinitselfand

byitsownnatureisgoodisanend，andacauseinthesensethatfor

itssaketheotherthingsbothcometobeandare，andsinceanendor

purposeistheendofsomeaction，andallactionsimplychange？Soin

thecaseofunchangeablethingsthisprinciplecouldnotexist，nor

couldtherebeagooditself。Thisiswhyinmathematicsnothingis

provedbymeansofthiskindofcause，noristhereany

demonstrationofthiskind-’becauseitisbetter，orworse’；indeedno

oneevenmentionsanythingofthekind。Andsoforthisreasonsomeof

theSophists，e。g。Aristippus，usedtoridiculemathematics；forin

thearts(hemaintained)，evenintheindustrialarts，e。g。in

carpentryandcobbling，thereasonalwaysgivenis’becauseitis

better，orworse，’butthemathematicalsciencestakenoaccountof

goodsandevils。

Butifthereareseveralsciencesofthecauses，andadifferent

scienceforeachdifferentprinciple，whichofthesesciencesshould

besaidtobethatwhichweseek，orwhichofthepeoplewhopossess

themhasthemostscientificknowledgeoftheobjectinquestion？

Thesamethingmayhaveallthekindsofcauses，e。g。themovingcause

ofahouseistheartorthebuilder，thefinalcauseisthe

functionitfulfils，thematterisearthandstones，andtheformis

thedefinition。Tojudgefromourpreviousdiscussionofthe

questionwhichofthesciencesshouldbecalledWisdom，thereis

reasonforapplyingthenametoeachofthem。Forinasmuchasitis

mostarchitectonicandauthoritativeandtheothersciences，like

slavewomen，maynotevencontradictit，thescienceoftheendand

ofthegoodisofthenatureofWisdom(fortheotherthingsarefor

thesakeoftheend)。Butinasmuchasitwasdescribed’asdealing

withthefirstcausesandthatwhichisinthehighestsenseobjectof

knowledge，thescienceofsubstancemustbeofthenatureofWisdom。

Forsincemenmayknowthesamethinginmanyways，wesaythathewho

recognizeswhatathingisbyitsbeingsoandsoknowsmorefully

thanhewhorecognizesitbyitsnotbeingsoandso，andinthe

formerclassitselfoneknowsmorefullythananother，andheknows

mostfullywhoknowswhatathingis，nothewhoknowsitsquantityor

qualityorwhatitcanbynaturedoorhavedonetoit。Andfurtherin

allcasesalsowethinkthattheknowledgeofeachevenofthe

thingsofwhichdemonstrationispossibleispresentonlywhenweknow

whatthethingis，e。g。whatsquaringarectangleis，viz。thatit

isthefindingofamean；andsimilarlyinallothercases。Andwe

knowaboutbecomingsandactionsandabouteverychangewhenweknow

thesourceofthemovement；andthisisotherthanandopposedto

theend。Thereforeitwouldseemtobelongtodifferentsciencesto

investigatethesecausesseverally。

But(2)，takingthestarting-pointsofdemonstrationaswellas

thecauses，itisadisputablequestionwhethertheyaretheobjectof

onescienceorofmore(bythestarting-pointsofdemonstrationImean

thecommonbeliefs，onwhichallmenbasetheirproofs)；e。g。that

everythingmustbeeitheraffirmedordenied，andthatathing

cannotatthesametimebeandnotbe，andallothersuch

premisses:-thequestioniswhetherthesamesciencedealswiththemas

withsubstance，oradifferentscience，andifitisnotone

science，whichofthetwomustbeidentifiedwiththatwhichwenow

seek-Itisnotreasonablethatthesetopicsshouldbetheobjectof

onescience；forwhyshoulditbepeculiarlyappropriatetogeometry

ortoanyothersciencetounderstandthesematters？Ifthenit

belongstoeverysciencealike，andcannotbelongtoall，itisnot

peculiartothesciencewhichinvestigatessubstances，anymorethan

toanyotherscience，toknowaboutthesetopics-And，atthesame

time，inwhatwaycantherebeascienceofthefirstprinciples？

Forweareawareevennowwhateachoftheminfactis(atleast

evenothersciencesusethemasfamiliar)；butifthereisa

demonstrativesciencewhichdealswiththem，therewillhavetobe

anunderlyingkind，andsomeofthemmustbedemonstrableattributes

andothersmustbeaxioms(foritisimpossiblethatthereshouldbe

demonstrationaboutallofthem)；forthedemonstrationmuststart

fromcertainpremissesandbeaboutacertainsubjectandprove

certainattributes。Thereforeitfollowsthatallattributesthat

areprovedmustbelongtoasingleclass；foralldemonstrative

sciencesusetheaxioms。

Butifthescienceofsubstanceandthesciencewhichdealswith

theaxiomsaredifferent，whichofthemisbynaturemore

authoritativeandprior？Theaxiomsaremostuniversalandare

principlesofallthings。Andifitisnotthebusinessofthe

philosopher，towhomelsewillitbelongtoinquirewhatistrueand

whatisuntrueaboutthem？

(3)Ingeneral，doallsubstancesfallunderonescienceor

undermorethanone？Ifthelatter，towhatsortofsubstanceisthe

presentsciencetobeassigned？-Ontheotherhand，itisnot

reasonablethatonescienceshoulddealwithall。Forthentherewould

beonedemonstrativesciencedealingwithallattributes。Forever

demonstrativescienceinvestigateswithregardtosomesubjectits

essentialattributes，startingfromthecommonbeliefs。Thereforeto

investigatetheessentialattributesofoneclassofthings，

startingfromonesetofbeliefs，isthebusinessofonescience。

Forthesubjectbelongstoonescience，andthepremissesbelongto

one，whethertothesameortoanother；sothattheattributesdoso

too，whethertheyareinvestigatedbythesesciencesorbyone

compoundedoutofthem。

(5)Further，doesourinvestigationdealwithsubstancesalone

oralsowiththeirattributes？Imeanforinstance，ifthesolidis

asubstanceandsoarelinesandplanes，isitthebusinessofthe

samesciencetoknowtheseandtoknowtheattributesofeachofthese

classes(theattributesaboutwhichthemathematicalsciencesoffer

proofs)，orofadifferentscience？Ifofthesame，thescienceof

substancealsomustbeademonstrativescience，butitisthoughtthat

thereisnodemonstrationoftheessenceofthings。Andifofanother，

whatwillbethesciencethatinvestigatestheattributesof

substance？Thisisaverydifficultquestion。

(4)Further，mustwesaythatsensiblesubstancesaloneexist，

orthatthereareothersbesidesthese？Andaresubstancesofonekind

orarethereinfactseveralkindsofsubstances，asthosesaywho

asserttheexistencebothoftheFormsandoftheintermediates，

withwhichtheysaythemathematicalsciencesdeal？-Thesenseinwhich

wesaytheFormsarebothcausesandself-dependentsubstanceshas

beenexplainedinourfirstremarksaboutthem；whilethetheory

presentsdifficultiesinmanyways，themostparadoxicalthingof

allisthestatementthattherearecertainthingsbesidesthosein

thematerialuniverse，andthatthesearethesameassensible

thingsexceptthattheyareeternalwhilethelatterareperishable。

Fortheysaythereisaman-himselfandahorse-itselfand

health-itself，withnofurtherqualification，-aprocedurelikethatof

thepeoplewhosaidtherearegods，butinhumanform。Fortheywere

positingnothingbuteternalmen，norarethePlatonistsmakingthe

Formsanythingotherthaneternalsensiblethings。

Further，ifwearetopositbesidestheFormsandthesensibles

theintermediatesbetweenthem，weshallhavemanydifficulties。For

clearlyonthesameprincipletherewillbelinesbesidesthe

lines-themselvesandthesensiblelines，andsowitheachoftheother

classesofthings；sothatsinceastronomyisoneofthese

mathematicalsciencestherewillalsobeaheavenbesidesthesensible

heaven，andasunandamoon(andsowiththeotherheavenlybodies)

besidesthesensible。Yethowarewetobelieveinthesethings？Itis

notreasonableeventosupposesuchabodyimmovable，buttosuppose

itmovingisquiteimpossible-Andsimilarlywiththethingsof

whichopticsandmathematicalharmonicstreat；forthesealsocannot

existapartfromthesensiblethings，forthesamereasons。Forif

therearesensiblethingsandsensationsintermediatebetweenFormand

individual，evidentlytherewillalsobeanimalsintermediate

betweenanimals-themselvesandtheperishableanimals-Wemightalso

raisethequestion，withreferencetowhichkindofexistingthingswe

mustlookforthesesciencesofintermediates。Ifgeometryisto

differfrommensurationonlyinthis，thatthelatterdealswith

thingsthatweperceive，andtheformerwiththingsthatarenot

perceptible，evidentlytherewillalsobeascienceotherthan

medicine，intermediatebetweenmedical-science-itselfandthis

individualmedicalscience，andsowitheachoftheothersciences。

Yethowisthispossible？Therewouldhavetobealsohealthythings

besidestheperceptiblehealthythingsandthehealthy-itself——Andat

thesametimenoteventhisistrue，thatmensurationdealswith

perceptibleandperishablemagnitudes；forthenitwouldhaveperished

whentheyperished。

Butontheotherhandastronomycannotbedealingwithperceptible

magnitudesnorwiththisheavenaboveus。Forneitherare

perceptiblelinessuchlinesasthegeometerspeaksof(forno

perceptiblethingisstraightorroundinthewayinwhichhe

defines’straight’and’round’；forahooptouchesastraightedgenot

atapoint，butasProtagorasusedtosayitdid，inhisrefutationof

thegeometers)，norarethemovementsandspiralorbitsintheheavens

likethoseofwhichastronomytreats，norhavegeometricalpoints

thesamenatureastheactualstars-Nowtherearesomewhosaythat

theseso-calledintermediatesbetweentheFormsandtheperceptible

thingsexist，notapartfromtheperceptiblethings，however，butin

these；theimpossibleresultsofthisviewwouldtaketoolongto

enumerate，butitisenoughtoconsiderevensuchpointsasthe

following:-Itisnotreasonablethatthisshouldbesoonlyinthe

caseoftheseintermediates，butclearlytheFormsalsomightbein

theperceptiblethings；forbothstatementsarepartsofthesame

theory。Further，itfollowsfromthistheorythattherearetwosolids

inthesameplace，andthattheintermediatesarenotimmovable，since

theyareinthemovingperceptiblethings。Andingeneraltowhat

purposewouldonesupposethemtoexistindeed，buttoexistin

perceptiblethings？Forthesameparadoxicalresultswillfollowwhich

wehavealreadymentioned；therewillbeaheavenbesidesthe

heaven，onlyitwillbenotapartbutinthesameplace；whichis

stillmoreimpossible。

(6)Apartfromthegreatdifficultyofstatingthecasetrulywith

regardtothesematters，itisveryhardtosay，withregardtothe

firstprinciples，whetheritisthegenerathatshouldbetakenas

elementsandprinciples，orrathertheprimaryconstituentsofa

thing；e。g。itistheprimarypartsofwhicharticulatesoundsconsist

thatarethoughttobeelementsandprinciplesofarticulatesound，

notthecommongenus-articulatesound；andwegivethenameof

’elements’tothosegeometricalpropositions，theproofsofwhich

areimpliedintheproofsoftheothers，eitherofallorofmost。

Further，boththosewhosaythereareseveralelementsofcorporeal

thingsandthosewhosaythereisone，saythepartsofwhichbodies

arecompoundedandconsistareprinciples；e。g。Empedoclessaysfire

andwaterandtherestaretheconstituentelementsofthings，but

doesnotdescribetheseasgeneraofexistingthings。Besidesthis，if

wewanttoexaminethenatureofanythingelse，weexaminetheparts

ofwhich，e。g。abedconsistsandhowtheyareputtogether，and

thenweknowitsnature。

Tojudgefromthesearguments，then，theprinciplesofthings

wouldnotbethegenera；butifweknoweachthingbyits

definition，andthegeneraaretheprinciplesorstarting-pointsof

definitions，thegeneramustalsobetheprinciplesofdefinable

things。Andiftogettheknowledgeofthespeciesaccordingto

whichthingsarenamedistogettheknowledgeofthings，thegenera

areatleaststarting-pointsofthespecies。Andsomealsoofthose

whosayunityorbeing，orthegreatandthesmall，areelementsof

things，seemtotreatthemasgenera。

But，again，itisnotpossibletodescribetheprinciplesin

bothways。Fortheformulaoftheessenceisone；butdefinitionby

generawillbedifferentfromthatwhichstatestheconstituent

partsofathing。