Self-reported happiness does not generally increase with rising income, as established by Richard Easterlin. We argue that the current debate in economics about the income-happiness paradox has paid too little attention to the theoretical foundation of the expected positive relation between income and happiness, seeking an empirical resolution through better data and more elaborate estimating equations instead. We return to the history of economics and revisit the contributions of Irving Fisher and Kenneth Boulding for the missing economic theory that underlies the income-happiness paradox. According to both Fisher and Boulding, “consumer capital” is the ultimate source of welfare, whereby consumer capital is defined as an accumulated stock of tangible and intangible instruments that yield a stream of services over their useful life. In the view of Fisher and Boulding, it is the utilization of this capital stock that renders happiness to individuals. Moreover, income that pays for the goods of consumption can be a “bad,” reflecting the cost of maintaining the consumer capital stock. Therefore, Fisher and Boulding’s insights bring a new perspective to the Easterlin paradox, showing that the empirical finding that rising income contributes only little, if anything, to levels of happiness has been overemphasized at the expense of the theoretically more relevant relation between consumer capital and happiness, and the exact role of income therein. [ABSTRACT FROM PUBLISHER]