subsequent first issue of the Greenbacks brought a welcome relief. Throughout the whole of the first year of the suspension, the volume of money was less than it had been in the preceding year. None the less, the gold stayed out of general circulation. It did not come back from abroad. And prices _rose_.[363] A similar episode, the obverse of this, occurred when the Bank of England _resumed_ specie payments in the early '20's. Then gold came back, the currency was increased, and, coincidently, _prices fell_.[364] I conclude that the conflict between Gresham's Law and the quantity theory is real and fundamental, and that in cases where different _qualities_ of money are in concurrent circulation, the undervalued money will leave, regardless of the question of quantity. CHAPTER XVII THE QUANTITY THEORY AND "WORLD PRICES" Some writers, who would call themselves quantity theorists, would repudiate many of the doctrines for which Fisher stands, and which the historical quantity theory involves. The recognition which Fisher's book has received from quantity theorists generally, justifies me in treating his book as the "official" exposition of the modern quantity theory, and, indeed, it is easy to show that Fisher is fundamentally true to the quantity theory tradition. With many writers, the disagreement with Fisher would be a mere matter of degree; they would hold that Fisher has set forth the central principle, that his qualitative reasoning is correct, but that the relations among the factors in his equation are less rigid than he maintains. As I reject even the qualitative reasoning by which Fisher defends his doctrine, and reject even the qualitative tendency which he maintains, my criticisms will apply as well to the position of this group of writers, though I should have less practical differences with them, to the extent that they admit qualifications and exceptions to Fisher's doctrine. There is, however, a group of writers who seem to feel that the quantity theory remains sufficiently vindicated if it can be shown that an increase in _gold production_ tends to raise prices throughout the world, while a check on gold production tends to lower prices, and who rest their case on the necessity which bankers find of keeping reserves in some sort of relation to the expansions of bank-credit.