making an addition to his hut, he proves that he values that gain ten times as highly as he does either of the others. Establishing values by means of such final costs is a process that goes on in every stage of social evolution. _Unlike Results of Creating Wealth and Using it Summarized._--Wealth, then, affects a man as a consumer in one way and the same man as a producer in an opposite way. In the one case the effects are favorable, and in the other they are unfavorable. At a certain test point the two effects may be equally strong as motives to action, and so may be said to be equivalent. The man is impelled to work by his desire for a final unit of wealth, and he is deterred from it by his aversion for the final unit of labor which he will have to incur if he secures the benefit. If he performs the labor and gets the benefit, he neither gains nor loses as the net result of this particular part of his labor, though from all other parts of his labor he gets a net surplus of benefit. It is natural to measure all such economic gains in terms of sacrifices incurred at the test point where these are greatest. This is the labor one would have to incur in order to add the means of gratification to his previous supply of consumers' goods. _Minimum Gains offset Maximum Pains._--Running through and through the economic process are these two different measuring operations. Man is forever estimating the amount of harm that wealth does him when he is in the act of producing it, and the amount of good it does him when he consumes it; and there is always to be found a point where the two amounts are equal. It is the point at which gains are smallest and sacrifices greatest. It is at this point that men measure values in primitive life and in civilized life. How in the intricate life of a modern society the measuring is done we shall in due time see; for the present it is enough that we perceive the universality of the law according to which value is best measured by the disutility of the labor which is most costly to the worker. Organized societies do something which is tantamount to this. It is as though the whole social organism were an individual counting the sacrifices of his most costly labor and getting therefrom a unit for comparing the effective utilities of different goods.