The Principles of Political Economy was one of the most important economics or political economy textbooks of the mid-nineteenth century.It was revised until its seventh edition in 1871 and published in numerous other editions.Besides discussing descriptive issues such as which nations tented to benifit more in a system of trade based on comparative advantage,the work also discussed normative issues such as ideal systems of political economy,critiquing proposed systems such as communism and socialism.

John Stuart Mill(20 May 1806-8 May 1873)was a British philosopher,political economist and civil servant. One of the most influential thinkers in the history of liberalism,he contributed widely to social theory,political theory and political economy.