The Wealth of Nations (PDF) (Print)

First published in 1776, The Wealth of Nations is considered the seminal work on political economy. Its author, Adam Smith, formulated the basic but groundbreaking concept that the natural human inclination toward self-interest results in prosperity. His passionate arguments in favor of free trade, rather than stringent government regulations, posit that individuals are entitled to set and regulate prices for their own goods and services. 
Smith's masterpiece of economic analysis was regarded as revolutionary upon its initial publication, and it continues to exert an active influence on modern politicians and economists. Rich in historical background and acute observations of the eighteenth-century, the book is also an insightful work of political philosophy. Witty and highly readable, it abounds in prescient theories that form the basis of today's capitalist system.