The following pages have as their central problem the value of money. But the value of money cannot be studied successfully as an isolated problem, and in order to reach conclusions upon this topic, it has been necessary to consider virtually the whole range of economic theory; the general theory of value; the rôle of money in economic theory and the functions of money in economic life; the theory of the values of stocks and bonds, of "good will", established trade connections, trade-marks, and other "intangibles"; the theory of credit; the causes governing the volume of trade, and particularly the place of speculation in the volume of trade; the relation of "static" economic theory to "dynamic" economic theory.