Social versus individual work preferences: implications for optimal linear income taxation

We extend the standard optimal linear income taxation model to allow for differences in social and individual work preferences while still maintaining the assumption that individuals are rational. The theoretical and simulation analyses show that when the government places a higher social weight on work than do individuals, the optimal marginal income tax rate (MIT) becomes lower. This implies lower revenue, income guarantee, and overall progressivity. The case for lower MIT is reinforced when the government places a relatively higher weight on work for low earners. Combining our analysis with that of An and Coady (2022), we, on the one hand, agree with previous studies that the optimal nonlinear income tax schedule would be close to the optimal linear one but, on the other, show that the degree of closeness would depend on preference differences. Our work contributes to the burgeoning field of non-welfarist economics.