102 MODERN MONETARY SYSTEMS 
phrases which express one and the same relation for the 
proof of a relation of cause and effect, currency deprecia- 
tion is said to “provoke” a rise in prices. This proposi- 
tion, very incorrectly stated, presupposes a relation of 
cause and effect, not between the rise in prices and the 
depreciation—expressions which are only applicable to 
one and the same phenomenon—but between the rise in 
prices or the depreciation and some factor to which it is 
attributed, such as an increase in the volume of currency. 
This is, no doubt, an hypothesis which deserves to be 
considered ; but it 1s desirable not to embody in a chain 
of reasoning, by a mere confusion of words and ideas, a 
notion which itself requires justification. Nevertheless it 
is supposed, in virtue of the old law of supply and de- 
mand, ‘“‘that prices change when the amount of currency 
varies, the amount of commodities remaining constant, 
and vice versa.” Starting with this principle, it is tempt- 
ing to attribute any upward or downward price movement 
to a change in the volume of currency. If all prices move 
at the same time and in the same direction, surely it is 
much more reasonable to attribute this general pheno- 
menon to some general cause than to suppose that changes 
are taking place in the various factors, such as the cost of 
production, which may separately exercise a similar in- 
fluence over the value of each of the objects sold. This 
plausible argument loses much of its force when we come 
to consider, on the one hand, that so-called ‘general ”’ 
upward or downward movements are often nothing but 
averages, and on the other that a rise in a few com- 
modities (raw materials, motive power, etc.),! with an 
effect upon the price of many others, is sufficient to pro- 
voke such average movements. Hence it appears that 
moderate variations occurring in periods undisturbed by crises 
need not necessarily be attributed, « priori, to a monetary 
cause. 
1'The relation between prices may also be more complicated, as shown 
by M. Ansiaux in his article on “Les prix solidaires” (Revue de I Institut 
de Sociologie), Vol. II, No. 2, March 1920. See also ‘“I'raité d’économie 
politique,” by the same author, and T. N. Carver, “Principles of Rural 
Economics,” p. 163, and Seligman, “Principles of Economics,” p. 253.