A valid price procedure, in my view, is essentially this: we take our quantitative value concept, summing up the multitudinous social forces which determine values: then we assume a given set of ethical, legal, and social values of a non-economic sort,[209] as a sort of frozen framework within which our economic values are to operate, and which shall remain constant during the investigation: then, measuring the economic values in terms of a common unit, we let them exert their influence on the situation, and see what results follow. We vary first one and then the other, and see what readjustments any change involves. Since the situation is so infinitely complex, we bring about this artificial simplicity in thought, that we may study the tendencies one by one. But a given economic change will work out its consequences fully only on the assumption that other economic changes are not occurring. We can in thought let them vary one by one, but they do in fact all vary at once. And further--and for this fact price theory has made no allowance--the "frozen framework" of legal, moral, and other non-economic social values, is not "frozen." Changes in economic values lead to readjustments, not only in the other economic values, but also in the legal, ethical, and other values of the framework. These last are fluid, psychic forces, just as truly as are the economic values. They change because of changes in the economic values; they initiate changes in the economic values; and they initiate changes which deflect the tendencies of changes in the economic values. So that, even though we premise a thoroughly organic theory of social value, in which the influence of the non-economic social values, working _through_ the economic values, is carefully provided for, we still have to correct the results of our price analysis, before applying it to practice, to account for changes in the non-economic values working to deflect the tendencies which the economic values would lead to if the other values had remained constant. This last, of course, most economists in practice constantly try to do. Present day discussions of practical economic problems are rich in data of a non-economic sort. In practice the economist recognizes that his mission is, not to see how far a few abstract factors will go in the explanation of economic life, but rather, to _explain_ that economic life by any means in his power, though he ransack heaven and earth in the process.