of income on a single consistent footing. Even had my logic been accurate, the customary attitudes and language of the business world would have presented insurmountable obstacles. But I claim to have done something towards the establishment of a consistent conception of supply and demand and market, applicable to all kinds of goods and services, productive or consumptive. This conception of market played a central rôle in all my later economic thinking. For it enabled me to resolve the supplies and demands of all concrete goods and services into costs and utilities reckoned in terms of human value, i.e. costs expressing painful or injurious experiences, utilities expressing pleasurable or beneficial experiences. This line of analysis led me to present economics in a distinctively qualitative character. For though concrete supplies and demands of goods and services and their prices still were reckoned in quantities, their human costs and utilities varied with the qualities of the persons who bore those costs or enjoyed those utilities. The issue of the apportionment of concrete costs and utilities among the different sexes and ages, capacities, and defects, of the producing and consuming population, stood out as of prime importance in reckoning the human value of any change of industrial processes or of standards of living. Thus, though an increase in the quantity of goods, turned out by improved technique, carried prima facie an increase in the means of enjoyment, both the amount and the nature of that
