Markets are useful instruments for organizing productive activity. But unless we want to let the market rewrite the norms that govern social institutions, we need a public debate about the moral limits of markets.

If you go back to Adam Smith, you find the idea that markets and market forces operate as an invisible hand. This is the traditional laissez-faire market idea. But today, when economics is increasingly defined as the science of incentive, it becomes clear that the use of incentives involves quite active intervention, either by an economist or a policy maker, in using financial inducements to motivate behavior. In fact, so much though that we now almost take for granted that incentives are central to the subject of economics.

Today if you look at most economic textbooks, economics is not defined by subject matter. It's presented as a science of social choice that applies not only to material goods - not only to flat-screen televisions - but to every decision we make, whether it's to get married, or to stay married, whether to have children and how to educate those children, or how to look after our health.

Some parents expend great efforts to get their kids into the right nursery school or the right preschool, with the thought that that will set them on the path to success, to competitive success especially.

There are some religious traditions that view human beings as participants in creation. This is true of the Jewish tradition, from which I come.

The norm of unconditional parental love, I think, depends on the fact that we don't pick and choose the traits of our children in the way that we pick and choose the features of a car we might order, or a consumer good.

Markets are useful instruments for organizing productive activity. But unless we want to let the market rewrite the norms that govern social institutions, we need a public debate about the moral limits of markets.