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.

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.

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.

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

Whether you're a libertarian liberal or a more egalitarian liberal, the idea is that justice means being non-judgmental with respect to the preferences people bring to public life.

A market economy is a tool - a valuable and effective tool - for organizing productive activity. A market society is a way of life in which market values seep into every aspect of human endeavour. It's a place where social relations are made over in the image of the market.

I think people who want to use genetic technologies to gain a competitive edge for their children are engaging in a kind of overreaching that could really undermine our appreciation of children as gifts for which we should be grateful and, instead, to view them as products or instruments that are there to be molded and directed.