One might experience some difficulty in understanding the sudden _volte-face_ of List in favour of free exchange in agriculture did we forget the particular situation in Germany, to which his thoughts always returned. This is equally true of many other points in his system. Germany was an exporter of corn and suffered from the operation of the English Corn Laws. German agriculture needed no protection, but suffered from want of markets, and List would have been very happy to persuade England to abandon her Corn Laws. Agricultural protection was only revived in Germany towards the end of 1879, when the agriculturists thought they were being threatened by foreign competition. II: SOURCES OF LIST’S INSPIRATION. HIS INFLUENCE UPON SUBSEQUENT PROTECTIONIST DOCTRINES. The question of the origin of List’s Protectionist ideas has frequently been raised. The works of the Frenchmen Dupin and Chaptal undoubtedly gave him some material for reflection, but he was really confirmed in his opposition to _laissez-faire_ by the men whom he met in America. While there he came into intimate contact with the members of a society which had been founded at Philadelphia for the encouragement of national industry. The founder of this society was an American statesman named Hamilton, the author of a celebrated report upon manufactures, who as far back as 1791 had advocated the establishment of Protection for the encouragement of struggling American industries.[593] Hamilton’s argument, as List fully recognised, bears a striking similarity to the thesis of the _National System_.[594] The Philadelphian society, which was then presided over by Matthew Carey (the father of the economist of whom we shall have to speak by and by), immediately after List’s arrival in America inaugurated an active campaign on behalf of a revision of the tariffs. Ingersoll, the vice-president, persuaded List to join in the campaign, which he did by publishing in 1827 a number of letters which caused quite a sensation.[595] They are really just a _résumé_ of the _National System_. The policy which in the course of a few years he was to advocate in Germany he now recommended to the consideration of the Americans. But facts were even more eloquent than books, and what chiefly struck the practical mind and the observant eye of List was the material success of American Protection, just as in Germany he had been impressed by the beneficial effects which temporary Protection enforced by the Continental Blockade had produced there.[596]