Asidefromperpetuating(使……持续存在)itself,thesolepurposeoftheAmericanAcademyandInstituteofArtsandLettersisto“foster,assistandsustainaninterest”inliterature,music,andart.Thisitdoesbyenthusiasticallyhandingoutmoney.Annualcashawardsaregiventodeservingartistsinvariouscategoriesofcreativity:architecture,musicalcomposition,theater,novels,seriouspoetry,lightverse,painting,sculpture.OneawardsubsidizesapromisingAmericanwriter’svisittoRome.ThereisevenanawardforaverygoodworkoffictionthatfailedcommerciallyoncewonbytheyoungJohnUpdikeforThePoorhouseFairand,morerecently,byAliceWalkerforInLoveandTrouble. Theawardsandprizestotalabout$750,000ayear,butmostofthemrangeinsizefrom$5,000to$12,500,awelcomesumtomanyyoungpractitionerswhoseworkmaynotbringinthatmuchmoneyinayear.Oneoftheadvantagesoftheawardsisthatmanygotothestrugglingartists,ratherthantothosewhoarealreadysuccessful.MembersoftheAcademyandInstitutearenoteligible(有资格的)foranycashprizes.Anotheradvantageisthat,unliketheNationalEndowmentfortheArtsorsimilarinstitutionsthroughouttheworld,thereisnogovernmentmoneyinvolved. Awardsaremadebycommittee.EachofthethreedepartmentsLiterature(120members),Art(83),Music(47)—hasacommitteedealingwithitsownfieldCommitteemembershiprotateseveryyear,sothatnewvoicesandopinionsareconstantlyheard. ThemostfinanciallyrewardingofalltheAcademy-InstituteawardsaretheMildredandHaroldStraussLivings.HaroldStrauss,adevotededitoratAlfredA.Knopf,theNewYorkpublishinghouse,andMildredStrauss,hiswife,werewealthyandchildless.TheylefttheAcademy-Instituteauniquebequest(遗赠):forfiveconsecutiveyears,twodistinguished(andfinanciallyneedy)writerswouldreceiveenoughmoneysotheycoulddevotethemselvesentirelyto“proseliterature”（noplays,nopoetry,andnopayingjobthatmightdistract).In1983,thefirstStraussLivingsof$35,000ayearwenttoshort-storywriterRaymondCarverandnovelist-essayistCynthiaOzick.By1988,thefundhadgrownenoughsothattwowinners,novelistsDianeJohnsonandRobertStone,eachgot$50,000ayearforfiveyears. Whatdoesthepassagemainlydiscuss?