The Price of Happiness

# Summary Researcher Matthew Killingsworth finds that happiness increases almost perfectly linearly with the logarithm of income—from $10,000 to over $500,000 annually—meaning each proportional increase in income (like a 10% raise) produces equal gains in happiness regardless of earning level. While individual dollars have sharply diminishing returns for personal happiness, redistributing money from higher to lower earners would produce exponentially larger gains in collective happiness. This mismatch between linear and exponential thinking about money may explain persistent income inequality and stagnant U.S. happiness levels despite rising wealth.