Now in one sense, it is my own contention that the price-_level_ can never be a _cause_ of anything. The price-level is an _average_. Averages may be _indicia_ of causation, but they are not themselves causes. They are not, in reality, anything _at all_. Causation is a matter which pertains to the particulars of which the average is made. But this is not the doctrine of the quantity theory. The quantity theory does, in certain connections, assign causal influence to the level of prices, particularly in the theory of foreign exchange, where the explanation of international gold movements rests on the doctrine that a price-level in one country, higher than the price-level of another country, drives money away.[332] It will be seen, in a moment, that Fisher relies on this principle to prove that the price-level of a country cannot rise without an increase of money--if it did so rise, it would drive out the money, and so be forced down again. The point at issue may be stated in terms of particular prices. The quantity theory is that, while particular prices may rise from causes affecting them, as compared with other prices, without a change in money, velocities, etc., still there cannot be a rise in the general average, because other prices will be obliged to go down to compensate. The issue is as to the possibility of a rise in particular prices, uncompensated by a corresponding fall in other particular prices, without a _prior_ increase in money, or velocities, or decrease in trade. I take up the issue in this form. I shall maintain that particular prices can, and do, rise, without a _prior_ increase in money or bank-deposits, or change in the volume of trade, or in velocity of money or deposits and also without compensating fall in other particular prices. Putting it in terms of Fisher's equation, I shall maintain, as against Fisher, that P can rise through the direct action of factors _outside_ the equation of exchange, that as a _consequence of such rise_ the other factors readjust themselves, and that a new equilibrium is reached which, in the absence of new disturbances from causes outside the equation, tends to be as permanent and stable as the old equilibrium was. In the argument which follows, I shall respect thoroughly the distinction between "normal" and "transitional" effects. I do not think that this distinction is properly drawn by Fisher. In my discussion of the relation between the volume of bank-credit and the volume of trade, and in other connections, I have shown that Fisher leaves out of his normal theory most of the concrete factors which do affect both the concrete magnitudes, and the long run _averages_, of the factors in his own equation. But for the present, I shall meet him on his own ground, give his distinctions their fullest weight, and carry my argument through the "transition" to a point where no further change among the factors in the equation can be expected as a consequence of the initial change assumed.