… is from page 16 of the 1983 collection of some of the writings of the late G. Warren Nutter, entitled Political Economy and Freedom; specifically, it’s from Nutter’s 1974 essay “Freedom in a Revolutionary Economy”:
The revolutionary content of the ideas popularized by Adam Smith and implemented by our Founders is to be found in the vision of a complex social order organized not by custom and command, the methods of the ages, but by voluntary exchange and association.
