In the struggle for Free Trade, as on other points, Smith was forestalled by the Physiocrats. But again has he shown himself superior in the breadth of his outlook. Physiocratic Liberalism was the result of their interest in agriculture, foreign trade being of quite secondary importance. Smith, on the other hand, considered foreign trade in itself advantageous, provided it began at the right moment and developed spontaneously.[230] Although his point of view is far superior to that of the Physiocrats, even Smith failed to give us a satisfactory theory. It was reserved for Ricardo and his successors, particularly John Stuart Mill, to find a solid scientific basis for the theory of international trade. The doctrine of the Scotch economist is somewhat lame. But the hesitancy of a great writer is often interesting, and some of his arguments deserve to be recalled. Already in our review of his theory of money we have become familiar with Smith’s criticism of the balance of trade theory. But the balance of trade theory is not the whole of Protection, and we find in Smith something more than its mere refutation. In the first place, we have a criticism of Protectionism in general considered in its Mercantilistic aspect, followed by an attempt to demonstrate the positive advantages of international commerce. The first criticism that he offers might be summed up in the well-known phrase: “Industry is limited by capital.” “The general industry of the society can never exceed what the capital of the society can employ.” But Protection, perhaps, increases the quantity of capital? No, “for it can only divert a part of it into a direction into which it might not otherwise have gone.” But the direction spontaneously given to their capital by individuals is the most favourable to a country’s industry. Has not Smith demonstrated this already? Protection, consequently, is not merely useless; it may even prove injurious.[231] The argument does not appear decisive, especially when we recall the criticism of Smith’s optimism given above. To borrow an expression of M. Pareto, it is the maximum of ophelimity and not the maximum of utility that is realised by the capitalists under the action of personal interest.