What then of all those among free men who voluntarily place themselves in the service of those we have been discussing, conveying their products the products of farming and the other sorts of expertise between them, and establishing equality between these products; some in market places, others moving from one city to another, whether by sea or by land, exchanging currency both for everything else and for itself people to whom we give the names of 'money changers', 'merchants', 'ship owners', and 'retailers': surely they won't lay claim at all to the art of statesmanship?