Economics
Adam Smith on the natural ordering Tendency of Free Markets, or what he called the "Invisible Hand" (1776)
Found in: An Inquiry Into the Nature and Causes of the Wealth of Nations (Cannan ed.), vol. 1
... by directing that industry in such a manner as its produce may be of the greatest value, he intends only his own gain, and he is in this, as in many other cases, led by an invisible hand to promote an end which was no part of his intention.