这是维基百科里对政治经济学的定义  ，发展历史
  Political economy originally was the term for studying production, buying and selling, and their relations with law, custom, and government, as well as with a distribution of national wealth including through the budget process. Political economy originated in moral philosophy. It developed in the 18th century as the study of the economies of states, polities, hence political economy.
In the late nineteenth century, the term 'economics' came to replace 'political economy', coinciding with publication of an influential textbook by Alfred Marshall in 1890.[1] Earlier, William Stanley Jevons, a proponent of mathematical methods applied to the subject, advocated 'economics' for brevity and with the hope of the term becoming "the recognised name of a science."[2][3]
Today, political economy, where it is not used as a synonym for economics, may refer to very different things, including Marxian analysis, applied public-choice approaches emanating from the Chicago school, or simply the advice given by economists to the government or public on general economic policy or on specific proposals.[3] A rapidly-growing mainstream literature from the 1970s has expanded beyond the model of economic policy in which planners maximize utility of a representative individual toward examining how political forces affect the choice of policies, especially as to distributional conflicts and political institutions.[4] It is available as an area of study in certain colleges and universities.

History of the term
Originally, political economy meant the study of the conditions under which production or consumption within limited parameters was organized in the nation-states. The phrase économie politique (translated in English as political economy) first appeared in France in 1615 with the well known book by Antoine de Montchrétien: Traité de l’economie politique. French physiocrats, Adam Smith, David Ricardo and German philosopher and social theorist Karl Marx were some of the exponents of political economy. In 1805, Thomas Malthus became England's first professor of political economy, at the East India Company College, Haileybury, Hertfordshire. The world's first professorship in political economy was established in 1763 at the University of Vienna, Austria; Joseph von Sonnenfels was the first tenured professor.
In the United States, political economy first was taught at the College of William and Mary; in 1784 Adam Smith's Wealth of Nations was a required textbook.[5]
Glasgow University, where Smith was Professor of Logic and Moral Philosophy, changed the name of its Department of Political Economy to the Department of Economics (ostensibly to avoid confusing prospective undergraduates) in academic year 1997–1998, making the class of 1998 the last to be graduated with a Scottish Master of Arts degree in Political Economy.

资料来源：http://en.wikipedia.org/wiki/Political_economy