We find a U-shaped relation between happiness and religiosity in cross-country panel data after controlling for income levels. At a given level of income, the same level of happiness can be reached with high and low levels of religiosity, but not with intermediate levels. A rise in income causes an increase in happiness along with a decline of religiosity. Our interpretation of the empirical results is that the indifference curves for religiosity and other commodities of the utility function are hump-shaped.
happiness religiosity utility function long-run development