Treść książki

Przejdź do opcji czytnikaPrzejdź do nawigacjiPrzejdź do informacjiPrzejdź do stopki
Spaceisnottheonlyobjecttowhichweascribecontinuousstructure.The
intensityofstream,orofcolor,seemtohavethisquality.But,aboveall,itis
theflowoftimethatiscontinuous.
Alooseandfreestructure,composedofisolatedelements,istheopposite
ofacontinuousstructure.Suchastructureissaidtobediscrete.Theword
“discrete”isderivedfromtheLatindiscretus,separate,detachedfromother
things.“Discrete”thusmeans“consistingof,orpertainingto,distinctand
individualparts.”
Thenumbers
1,2,3,
formadiscretestructure.
Couldspacebediscrete?Thiscannotberuledoutapriori.Norcanwerule
outofpossibilitythattheflowoftimemightbediscrete.
Geometry,themathematicalscienceofspace,hasalsoanother,moremun-
daneorigin.ThetworelevantGeekwordaregea1land(wemeanarableland)
andmetrein1tomeasure.Proclus(ca.4101485),acommentatorofworksof
hispredecessors,wrotethat“Manypeopleassertthatgeometrywasinvented
byEgyptiansformeasurementofland.Theyneededitbecausetheinhabitants
oftheNilewashedoutbalks.”
Frombalkstoinfinitelydivisibleexistence1abreathtakingspan.
Spaceisacompositeobjectmadeupofelementsthatenableustorealize
thenatureofthewhole.Wesingleoutpoints1placesinspace.Thisisnot
adefinitionbutjustanothertermoflanguage.Pointsarenotpartsofspace:we
donotattributethemamaterialnatureevenwhenwearepreparedtoattribute
amaterialnaturetospace.Theyarenotarawmaterialoutofwhichspace,or
apartofit,iscomposed.Whenwethinkofapoint,wethinkofitslocation.
Apointisasynonymofitsneighbourhood.Onlyifthespaceisnotuniform,
theseneighbourhoodsmaybedifferent.
Nevertheless,wearewillingtoimaginepointsasindependentexistences,
andthethoughtthattheycouldbetherawmaterialofspacedoesnotalways
strikeusasalien.Thisdilemmaisoneofthedifficultiesweencounterwhen
wethinkofthenotionofacontinuum.
Anotherdifficultyistheinfinitudeofspace,anotionwhichsuggestitself
irresistiblywhenwethinkofstraightlines,yetanotherelementofspace.
Afterafewattemptswegiveuptheideaofdefiningastraightline.Itseems
tobeasprimitiveastheconceptofspace.Onecanalsoadoptthereverseview
10