▁novel - length ▁works ▁of ▁science ▁fiction ▁include ▁spec ulation ▁( direct ly ▁or ▁indirect ly ) ▁on ▁modes ▁of ▁life ▁and ▁behaviour . ▁They ▁are ▁sometimes ▁alleg or ical ▁and ▁often ▁serious ▁attempts ▁to ▁model ▁possible ▁future ▁soci eties , ▁political ▁institutions ▁and ▁systems . ▁Ex amples ▁include ▁Harry ▁Harrison ' s ▁novel ▁Make ▁Room ! ▁Make ▁Room !, ▁The ▁Dis poss essed ▁by ▁Urs ula ▁K . ▁Le ▁Gu in ; ▁and ▁the ▁Host ile ▁Take over ▁Tr il ogy ▁by ▁S . ▁Andrew ▁Sw ann . ▁ ▁Im ag ined ▁soci eties ▁may ▁be ▁based ▁on ▁very ▁different ▁assumptions . ▁O ften ▁the ▁future ▁is ▁mode led ▁on ▁historic ▁forms ▁- ▁fe ud al ism , ▁ ▁or ▁in ▁the ▁case ▁of ▁The ▁Foundation ▁series , ▁the ▁Roman ▁Empire . ▁ ▁A ▁common ▁theme ▁is ▁the ▁integration ▁of ▁human ity ▁into ▁some ▁greater ▁inter stell ar ▁society . ▁A ▁popular ▁modern ▁example ▁is ▁the ▁U pl ift ▁series ▁by ▁David ▁Br in ▁where ▁a ▁species ' ▁status ▁is ▁defined ▁based ▁on ▁the ▁concept ▁of ▁bi olog ically ▁u pl ifting ▁other ▁species . ▁ ▁U top ian ▁soci eties ▁ ▁The ▁term ▁U top ia ▁was ▁invent ed ▁by ▁Thomas ▁More ▁as ▁the ▁title ▁of ▁his ▁Latin ▁book ▁De ▁Opt imo ▁Re ip ublic ae ▁Stat u ▁de que ▁Nova ▁Ins ula ▁U top ia ▁( cir ca ▁ 1 5 1 6 ), ▁known ▁more ▁commonly ▁as ▁U top ia . ▁He ▁created ▁the ▁word ▁" ut op ia