The true maxim is to exclude no nation from one’s commerce without very good reasons. The Japanese trade with only two nations, China and Holland. The Chinese receive a thousand percent profit on sugar, and sometimes just as much on the return shipment.  The Dutch make approximately equal profits. Every nation that behaves according to Japanese maxims will necessarily be cheated. It is competition that sets a fair price on merchandise and establishes true relations among them.
Even less must a state restrict itself to selling its products to a single nation under pretext that she will take all of them at a certain price. The Polish made such a deal for their grain with the city of Danzig ; several kings in the Indies have similar contracts for spices with the Dutch.  These conventions are the lot of a poor nation which is willing to give up the hope of getting rich provided she has an assured subsistence, or of nations whose servitude consists in sacrificing the use of the things which nature had provided them, or making a disadvantageous trade.