Women may want greater taxes and redistributional spending than men if malein comes exceed female incomes and men and women are not always married. Cross-section evidence from opinion polls provides indirect support for this view.Women express greater favorability toward redistributional spending than do men; the difference is explained largely but not entirely by income differences. The empirical analysis provides partialsupport for Meltzer and Richard (1981) , and suggests that increases in singleness after World WarII may have acted to increase differences by sex in desired redistributional spending.

We calculate the harm a birth imposes on others when greenhouse gas emissions are a problem and a cap limits emissions damage. This negative population externality, which equals the corrective Pigovian tax on having a child, is substantial in calibrations. In our base case, the Pigovian tax is 21 percent of a parent's lifetime income in steady state and 5 percent of lifetime income immediately after imposition of a cap, per child. The optimal population in steady state, which maximizes utility taking account of the externality, is about one quarter of the population households would choose voluntarily