My argument is not that we must never intervene in nature. My argument is that there is a moral difference between intervention for the sake of health, to cure or prevent disease, and intervention for the sake of achieving a competitive edge for our kids in a consumer society.

The majority of American states had laws by the 1930s that allowed for forced sterilization of socially undesirable categories of people, so-called feeble-minded, for example, and with Hitler culminating in genocide.

If parents are aiming at choosing children who will be good athletes, or great musicians, or who will get into Ivy League schools, or who will be tall enough to make the basketball team, then there is a danger that the life of the child will bear the burden of that expectation; and the risk of disappointment and the cost of disappointment will be even higher than they are now, and even now they can be considerable.

There are really exercises in a kind of consumerist ethic that I think don't have the same moral weight as medicine or health.

I think too often in our society parents, who may have good impulses, overreach and try to mold and shape and direct their child.

One can imagine a kind of hormonal arms race or genetic arms race, whether it's to do with height or IQ, conceivably, in the future. So it's limitless, and that's another of the features that sets it apart from medical intervention.

The way things are does not determine the way they ought to be