Political Economy was the original term for the study of production, the acts of buying and selling, and their relationships to laws, customs and government. It developed in 18th century as the study of the economies of states (also known as polities, hence the word "political" in "political economy"). First introduced by John Locke, developed by Adam Smith and later Karl Marx labor is the real source of value versus land or capital. Econmics began to be used in the latter part of the 19th century as the discipline began to focus on a mathematical basis for validatino rather than looking at the relationship between the production of goods of services and their consumption. In my experience as an economist I feel, that the reason we continue this trend today is that the reduction of philosophy to an equation that can be carried around in your wallet is twofold: First and foremost if most people don't understand the math, you can look like a genius and academia requires itself to be incomprehensible to the comman folk for their own self-worth programs. Secon, and perhaps maybe more important is that with the unfortunate increasing number of non-English speaking people's overrunning the American University system, mathematics is the only language that fully translates from one country to another. Political economy is on the rebound today in that there are groups of scholars who are looking at the relationship between several fields of study to show how the political environment and institutions influence market behavior.