▁orig ination ▁or ▁responsibility ▁cannot ▁be ▁assigned ▁for ▁any ▁given ▁decision . ▁ ▁E ff ort s ▁of ▁will ▁theory ▁is ▁related ▁to ▁the ▁role ▁of ▁will ▁power ▁in ▁decision ▁making . ▁It ▁suggests ▁that ▁the ▁ind et erm in acy ▁of ▁agent ▁vol ition ▁processes ▁could ▁map ▁to ▁the ▁ind et erm in acy ▁of ▁certain ▁physical ▁events   – ▁and ▁the ▁out comes ▁of ▁these ▁events ▁could ▁therefore ▁be ▁considered ▁caused ▁by ▁the ▁agent . ▁Mod els ▁of ▁vol ition ▁have ▁been ▁constructed ▁in ▁which ▁it ▁is ▁seen ▁as ▁a ▁particular ▁kind ▁of ▁complex , ▁high - level ▁process ▁with ▁an ▁element ▁of ▁physical ▁ind et erm in ism . ▁An ▁example ▁of ▁this ▁approach ▁is ▁that ▁of ▁Robert ▁K ane , ▁where ▁he ▁hypoth es izes ▁that ▁" in ▁each ▁case , ▁the ▁ind et erm in ism ▁is ▁function ing ▁as ▁a ▁h ind rance ▁or ▁obst acle ▁to ▁her ▁real izing ▁one ▁of ▁her ▁purposes   – ▁a ▁h ind rance ▁or ▁obst acle ▁in ▁the ▁form ▁of ▁resistance ▁within ▁her ▁will ▁which ▁must ▁be ▁overcome ▁by ▁effort ." ▁According ▁to ▁Robert ▁K ane ▁such ▁" ult imate ▁responsibility " ▁is ▁a ▁required ▁condition ▁for ▁free ▁will . ▁An ▁important ▁factor ▁in ▁such ▁a ▁theory ▁is ▁that ▁the ▁agent ▁cannot ▁be ▁reduced ▁to ▁physical ▁neur onal ▁events , ▁but ▁rather ▁mental ▁processes ▁are ▁said ▁to ▁provide ▁an ▁equally ▁valid ▁account ▁of ▁the ▁determ ination ▁of ▁outcome ▁as ▁their ▁physical ▁processes ▁( see ▁non - re duct ive ▁physical