They say the state should not impose on its citizens a preferred way of life, but should leave them as free as possible to choose their own values and ends, consistent with a similar liberty for others.

I am trying to get at the moral arguments and the ethical status of various attempts at enhancement, or genetic engineering, or the bid for designer children. But there are implications for society at large.

If we go too far down the road of choosing the genetic traits of children, my worry is that parenting will be less a kind of school for humility than it should be, and we will become too accustomed to regarding children as instruments of our ambition and of our desires.

Very often when we aim at the best, or what we may think is the best for our children, we aim really at lesser things, such as getting into a certain college.

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.

There's no necessary connection between maximizing social utility or economic wealth and creating a flourishing democracy. The first does not guarantee the second. The only way to create a flourishing democracy is to find ways to reason together about the big questions, including hard questions about justice and the common good, to reason together about these questions so that we as citizens can decide how to shape the forces that govern our lives.

I'm a supporter of embryonic stem cell research. I do think there are very important moral and also religious questions at stake in the debate over embryonic stem cell research.