Whenthecultivatorhastogivetohislandlordhalfofthereturnstoeachdoseofcapitalandlaborthatheappliestotheland,itwillnotbetohisinteresttoapplyanydosesthetotalreturntowhichislessthantwiceenoughtorewardhim.If,then,heisfreetocultivateashechooses,hewillcultivatefarlessintensivelythanontheEnglishplan[fixedrent]；hewillapplyonlysomuchcapitalandlaboraswillgivehimreturnsmorethantwiceenoughtorepayhimself:sothathislandlordwillgetasmallershareevenofthosereturnsthanhewouldhaveontheplanofafixedpayment.[4]
WhatisimportanthereisthatMarshallsawthataccordingtothisanalysisthesharetenantwillbegettingaresidualreturnandthelandlordwillbegettingasmallerrentalinethanunderfixedrent.WhatisstrangeisthatMarshalldidnotquestionwhythelandlorddoesnotchooseinsteadafixedrentcontractorsellinghislandownershiptothetenantoutright.[5]AndwhatisnaturalisthatMarshallwasreluctanttoletthetenant'sresidualearningremainunexplained:
Ifthetenanthasnofixityoftenure,thelandlordcandeliberatelyandfreelyarrangetheamountofcapitalandlaborsuppliedbythetenantandtheamountofcapitalsuppliedbyhimselftosuittheexigenciesofeachspecialcase.[6]