L ehrer, Shechtman, and Leasure (hereafter LSL) give us an opportunity to amplify our theory of the value of children. Regrettably, much of their criticism flows from a misunderstanding of our theory-particularly, of its scope conditions. Some of the criticism, however, appears to derive from epistemological roots. LSL's comment concludes by claiming that we attempted to complement existing theories of fertility with a new theory. Yet there are no existing theories that can account for women's and couples' decisions to have children when their net instrumental value is negative, as it is in all advanced industrial societies. Ours is the first and only theory that explains this empirical puzzle. Becker's (1981) economic theory of fertility, which serves as the acknowledged foundation for LSL's comment, explains why women who earn lower wages in the labor market are likely to have more children than those who can command higher wages. Why anyone in an advanced industrial society would have any children at all remains a mystery, however. Despite its apparent complexity, the logic of Becker's fertility theory is actually quite simple. It purposely says nothing whatsoever about the value of children to parents; people can desire children for any number of reasons. Whatever these reasons may be, the greater the opportunity cost of having a child, the fewer children will be demanded and therefore the fewer will be born. This logic is unimpeachable, and we certainly have no quarrel with it as far as it goes. Becker's theory assumes precisely what our theory sets out to explain-namely, why people value children in the first place. His theory concerns the fertility of people who already have decided to have children. Before deciding whether to have a child, rational people must compare the expected value of a child with that of other goods, such as expensive cars, houses and alternative uses of time. Such decisions necessarily involve trade-offs between valued goods.