od ity ▁exchange ▁or ▁the ▁evolution ▁of ▁trad ing ▁processes ▁in ▁a ▁way ▁consistent ▁with ▁historical ▁material ism ▁and ▁Marx ' s ▁theory ▁of ▁value . ▁So ▁a ▁better ▁approach , ▁it ▁is ▁argued , ▁is ▁to ▁regard ▁the ▁application ▁of ▁the ▁law ▁of ▁value ▁as ▁being ▁modified ▁in ▁the ▁course ▁of ▁the ▁expansion ▁of ▁trade ▁and ▁mark ets , ▁including ▁more ▁and ▁more ▁of ▁production ▁in ▁the ▁circuit ▁of ▁capital . ▁In ▁that ▁case , ▁a ▁specific ▁society ▁must ▁be ▁investig ated ▁to ▁discover ▁the ▁reg ulating ▁role ▁that ▁the ▁law ▁of ▁value ▁plays ▁in ▁economic ▁exchange . ▁ ▁Hein z ▁Di eter ich ' s ▁equivalence ▁economy ▁ ▁In ▁contemporary ▁Venezuela , ▁the ▁German ▁social ist ▁econom ist ▁Hein z ▁Di eter ich ▁has ▁argued ▁that ▁the ▁production ▁and ▁distribution ▁of ▁products ▁should ▁occur ▁in ▁accord ance ▁with ▁their ▁true ▁labour ▁costs , ▁as ▁shown ▁by ▁special ▁macro - e conom ic ▁labour ▁accounts ▁estim ating ▁how ▁much ▁work - time ▁products ▁take ▁to ▁make ▁( in ▁social ism ▁of ▁the ▁ 2 1 st ▁century ▁this ▁is ▁called ▁" equ ival ence ▁economy "). ▁The ▁idea ▁here ▁is ▁that ▁people ▁" get ▁even " ▁when ▁they ▁get ▁just ▁as ▁much ▁work ▁back , ▁as ▁they ▁put ▁in ▁themselves . ▁ ▁However , ▁this ▁argument ▁is ▁very ▁controvers ial . ▁Its ▁critics ▁claim ▁equivalence ▁economy ▁is ▁pract ically ▁impossible , ▁and ▁some ▁indeed ▁point ▁to ▁Marx ' s ▁re jection ▁in ▁the ▁Grund ris se ▁of ▁the ▁" time - ch