What did Adam Smith achieve?

Smith did manage to do in the Wealth of Nations, and for the first time, was to examine in a systematic way what much of the earlier literature of political economy had approached in a piecemeal manner-as a set of individual, largely disparate or unconnected economic phenomena and problems.

From After Adam Smith: A Century of Transformation in Politics and Political Economy (Princeton Univerity Press, 2009) by Murray Milgate and Shannon C. Stimson.