15。OftheCommerceoftheRomanswiththeBarbarians。TheRomanshavingerectedavastempireinEurope，Asia，andAfrica，theweaknessofthepeopleandthetyrannyoftheirlawsunitedallthepartsofthisimmensebody。TheRomanpolicywasthentoavoidallcommunicationwiththosenationswhomtheyhadnotsubdued：thefearofcarryingtothemtheartofconqueringmadethemneglecttheartofenrichingthemselves。
Theymadelawstohinderallcommercewithbarbarians。\"Letnobody，\"
saidValensandGratian，[115]\"sendwine，oil，orotherliquorstothebarbarians，thoughitbeonlyforthemtotaste。\"\"Letnoonecarrygoldtothem，\"addGratian，Valentinian，andTheodosius；[116]\"rather，iftheyhaveany，letoursubjectsdeprivethemofitbystratagem。\"Theexportationofironwasprohibitedonpainofdeath。
Domitian，aprinceofgreattimidity，orderedthevinesinGaultobepulledup，[117]fromfear，nodoubt，lesttheirwinesshoulddrawthitherthebarbarians。ProbusandJulian，whohadnosuchfears，gaveordersfortheirbeingplantedagain。
IamsensiblethatuponthedeclensionoftheRomanempirethebarbariansobligedtheRomanstoestablishstapletowns，andtotradewiththem。ButeventhisisaproofthatthemindsoftheRomanswereaversetocommerce。[118]