商业即交换，交换源于分工，而交换的最终目的是互利。亚当斯密是极其反对各种消极贸易政策、反对贸易战的，痛斥各种零和博弈思维。但他也反对商人的短视、垄断成为国际政治的主流出发点，在《国富论》第四编第三章结尾，他很有力地说到：

By such maxims as these, however, nations have been taught that their interest consisted in beggaring all their neighbours. Each nation has been made to look with an invidious eye upon the prosperity of all the nations with which it trades, and to consider their gain as its own loss. Commerce, which ought naturally to be, among nations as among individuals, a bond of union and friendship, has become the most fertile source of discord and animosity. The capricious ambition of kings and ministers has not, during the present and the preceding century, been more fatal to the repose of Europe, than the impertinent jealousy of merchants and manufacturers. The violence and injustice of the rulers of mankind is an ancient evil, for which, I am afraid, the nature of human affairs can scarce admit of a remedy: but the mean rapacity, the monopolizing spirit, of merchants and manufacturers, who neither are, nor ought to be, the rulers of mankind, though it cannot, perhaps, be corrected, may very easily be prevented from disturbing the tranquillity of anybody but themselves.

杨敬年是这样翻译的：

然而，由于这一类的原则，各国国民被教导说，他们的利益在于使所有的邻国变穷。每一个国家都变得用嫉妒的目光去看待和自己有商业往来的一切国家的繁荣，认为它们的利得就是自己的损失。在国家之间也像在个人之间一样，商业本来自然应当成为联合和友谊的纽带，但是现在却变成了争论和仇恨的最容易产生的源泉。在本世纪和上个世纪中，君主们和大臣们的反复多变的野心对于欧洲的安宁的影响，也不及商人和制造商的不恰当的妒忌的影响那么严重。人类统治者的横暴和不公正是一种古老的罪恶，对此我恐怕人类事务的本性是无法挽救的。但是商人和制造商不是也不应当是人类的统治者，他们的卑鄙的贪欲和垄断精神虽然或许是无法纠正的，但是可以很容易防止它去扰乱任何人（除了他们自己以外）的安宁。