Reason

           Halfayearlater,theboyshadchangedtheirminds.Theflameofagiantsunhadgivenwaytothesoftblacknessofspacebutexternalvariationsmeanlittleinthebusinessofcheckingtheworkingsofexperimentalrobots.Whateverthebackground,oneisfacetofacewithaninscrutablepositronicbrain,whichtheslide-rulegeniusessayshouldworkthus-and-so.

           Exceptthattheydon’t.PowellandDonovanfoundthatoutaftertheyhadbeenontheStationlessthantwoweeks.

           GregoryPowellspacedhiswordsforemphasis,"Oneweekago,DonovanandIputyoutogether."Hisbrowsfurroweddoubtfullyandhepulledtheendofhisbrownmustache.

           Itwasquietintheofficer’sroomonSolarStation#5–exceptforthesoftpurringofthemightyBeamDirectorsomewherefarbelow.

           RobotQT-1satimmovable.TheburnishedplatesofhisbodygleamedintheLuxitesandtheglowingredofthephotoelectriccellsthatwerehiseyes,werefixedsteadilyupontheEarthmanattheothersideofthetable.

           Powellrepressedasuddenattackofnerves.Theserobotspossessedpeculiarbrains.Oh,thethreeLawsofRoboticsheld.Theyhadto.AllofU.S.Robots,fromRobertsonhimselftothenewfloor-sweeper,wouldinsistonthat.SoQT-1wassafe!AndyettheQTmodelswerethefirstoftheirkind,andthiswasthefirstoftheQT’s.Mathematicalsquigglesonpaperwerenotalwaysthemostcomfortingprotectionagainstroboticfact.

           Finally,therobotspoke.Hisvoicecarriedthecoldtimbreinseparablefromametallicdiaphragm,"Doyourealizetheseriousnessofsuchastatement,Powell?"