If, however, there is a concerted movement to spend the surplus money, there results a general bidding down of the value of money, a general bidding up of the prices of goods.

At what point will this movement stop?
The rational conclusion must be that, other things being equal, the new equilibrium will be established when the ratio between the value of money and the price of the goods which each individual is purchasing becomes the same as before.

The money being doubled, prices must be doubled, and likewise for any other change in quantity.
Sec.10.

#The quantity theory of money.# This explanation of the effect of changes in the quantity of money in a country upon prices (the general scale of prices) is known as the quantity theory of money.
This theory has, for a century, been very generally accepted by competent students of the money problem.

It may be summed up thus: other things being equal, the value of the monetary unit, expressed in terms of all other commodities, falls as the quantity of money increases, and _vice versa_.