The German philosopher, Friedrich List (1789-1846) provided economics with the conceptual framework for regional economic integration with his advocacy of a Zollverein (customs union). List's nationalism led him to dismiss laissez-faire (free trade), advocated by Adam Smith and other classical economists, as unsuitable to the German aspirations. He therefore, came up with his proposal of the Zollverein as a counter-weight to the classical economists' advocacy of free trade. State and explain the guidelines establishing a Zollverein.