（3。iv。3）Theseareallobviouscauses。Thereisanothercause，whichrequiresrathermore
explanation。Iftwocountriescanbothofthemproducetwocommodities，corn，forexample，and
cloth，butnotbothcommodities，withthesamecomparativefacility，thetwocountrieswillfind
theiradvantageinconfiningthemselves，eachtooneofthecommodities，barteringfortheother。
Ifoneofthecountriescanproduceoneofthecommoditieswithpeculiaradvantages，andthe