I have constantly in view to separate and distinguish the principles of foreign trade, from those which only influence the advancement of an inland commerce, and a brisk circulation: operations which produce very different effects, equally meriting the attention of a statesman. The very existence of foreign trade, implies a separate interest between those nations who are found on the opposite side of the mercantile contract, as both endeavour to make the best bargain possible for themselves. These transactions imply a mutual dependence upon one another, which may either be necessary or contingent. It is necessary, when one of the nations cannot subsist without the assistance of the other, as is the case between the province of Holland, and those countries which supply it with grain; or contingent, when the wants of a particular nation cannot be supplied by their own inhabitants, from a want of skill and dexterity, only. Wherever, therefore, one nation finds another necessarily depending upon her for particular branches of traffic, there is a certain foundation for foreign trade; where the dependence is contingent, there is occasion for management, and for the hand of an able statesman. The best way to preserve every advantage, is, to examine in how far they are necessary, and in how far they are only contingent, to consider in what respect the nation may be most easily rivalled by her neighbours, and in what respect she has natural advantages which cannot be taken from her. The natural advantages are chiefly to be depended on: France, for example, can never be rivalled in her wines. Other countries may enjoy great advantages from their situation, mines, rivers, sea ports, fishing, timber, and certain productions proper to the soil. If you abstract from these natural advantages, all nations are upon an equal footing as to trade. Industry and labour are no properties attached to place, any more than oeconomy and sobriety. This proposition may be called in question, upon the principles of M. de Montesquieu, who deduces the origin of many laws, customs, and even religions, from the influence of the climate. That great man reasoned from fact and from experience, and from the power and tendency of natural causes, to produce certain effects when not checked by other circumstances; but in my method of treating this subject, I suppose these causes never to be allowed to produce their natural and immediate effects, when such effects would be followed by a political inconvenience: because I constantly suppose a statesman at the head of government, who makes every circumstance concur in promoting the execution of the plan he has laid down.