value. He knew that inflation by paper money similarly sent prices up. He was enthusiastic for a gold standard, not as being perfect, but being the best available.[51] Mill’s still valuable chapter on International Trade and all current economic doctrine on currency are Ruskinian economy too. Also, when a disciple of the much depreciated Manchester School talked of _laisser faire_ he generally meant: “Let Protection alone.” His phrase was general, but in the days of Gladstone’s chancellorships of the exchequer, the “Manchester” man was thinking mainly of the removal of tariffs. It would not be in accord with human psychology if the principle had not been pushed too far, and by friends and opponents alike the principle of governmental abstention from interference enlarged, and made universal. In calling for government action to determine wages and organize employment, Ruskin was simply uttering a need not yet felt. He was a twentieth century voice, heard too soon. But we must always avoid the snare into which the earlier economists fell, of assuming that their conclusions were rigid and absolutely correct. There can be no mechanical infallibility about Economics; it is not accurate enough to be mathematically true. It expresses tendencies. In a word, it is a psychological, not a physical science. Its subject is not wealth, simply, but human motive in regard to wealth. Students of the Political Economy of Adam Smith, Ricardo, Bentham and James Mill, find that these great founders of economic science, in whose debt we shall ever remain, assumed too much mechanical uniformity in men’s actions, and did not give enough weight to the reaction of man upon his circumstances. They counted a man too much as a passively responsive machine. This is what led them to the doctrines since so seriously modified--the existence of a fixed Wages Fund, the “Iron Law of Wages,” the thesis that “A demand for Commodities is not a demand for Labour.” John Stuart Mill began life under these influences, and his _Principles of Political Economy_ contain them; but in later life he abandoned his Wages Fund theory, gave greater weight to the human side, the variable and uncertain factor in economic problems, and under the influence of Comte and of the Socialists doubted the accuracy of much of his economic argument. This change was published in his review of the work of his friend Thornton, who had attacked the Wages Fund theory in 1869. It is in Mill’s collected Essays. The Political Economy which Ruskin attacked was that of Mill’s _Principles_; and to judge fairly of the controversy we must treat the science, not as it was left, in high universal abstraction, by Ricardo; nor as worked up with rich historical material, cautious and well informed, as in Professor Marshall’s writings, but (between these) as Mill left it in his first edition of 1848.