127。Ithavingbeenshewnthattherearenoabstractideasoffigure，andthatitisimpossibleforusbyanyprecisionofthoughttoframeanideaofextensionseparatefromallothervisibleandtangiblequalitieswhichshallbecommonbothtosightandtouch：thequestionnowremainingis，whethertheparticularextensions，figures，andmotionsperceivedbysightbeofthesamekindwiththeparticularextensions，figures，andmotionsperceivedbytouch？InanswertowhichIshallventuretolaydownthefollowingproposition：Theextension，figures，andmotionsperceivedbysightarespecificallydistinctfromtheideasoftouchcalledbythesamenames，noristhereanysuchthingasoneideaorkindofideacommontobothsenses。Thispropositionmaywithoutmuchdifficultybecollectedfromwhathathbeensaidinseveralplacesofthisessay。
Butbecauseitseemssoremotefrom，andcontraryto，thereceivednotionsandsettledopinionofmankind，Ishallattempttodemonstrateitmoreparticularlyandatlargebythefollowingarguments。
128。WhenuponperceptionofanideaIrangeitunderthisorthatsort，itisbecauseitisperceivedafterthesamemanner，orbecauseithasalikenessorconformitywith，oraffectsmeinthesamewayas，theideasofthesortIrankitunder。Inshort，itmustnotbeentirelynew，buthavesomethinginitoldandalreadyperceivedbyme。Itmust，Isay，havesomuchatleastincommonwiththeideasIhavebeforeknownandnamedastomakemegiveitthesamenamewiththem。Butithasbeen，ifImistakenot，clearlymadeoutthatamanbornblindwouldnotatfirstreceptionofhissightthinkthethingshesawwereofthesamenaturewiththeobjectsoftouch，orhadanythingincommonwiththem；butthattheywereanewsetofideas，perceivedinanewmanner，andentirelydifferentfromallhehadeverperceivedbefore：sothathewouldnotcallthembythesamename，norreputethemtobeofthesamesortwithanythinghehadhithertoknown。
129。Secondly，lightandcoloursareallowedbyalltoconstituteasonorspeciesentirelydifferentfromtheideasoftouch：norwillanyman，Ipresume，saytheycanmakethemselvesperceivedbythatsense：butthereisnootherimmediateobjectofsightbesideslightandcolours。
Itisthereforeadirectconsequencethatthereisnoideacommontobothsenses。