Bill Joy: I think we should distinguish between modifications that effect only you and modifications that might affect all your children. In the case of engineering to fix defects in your person, I don’t see any particular reason to constrain that. I think that’s a matter of personal choice. The issue of what kind of genetic modifications we ought to make that can be heritable, that can be passed on to your children is an issue of regulation. There’s clearly a societal cost to—unintended consequences of such modifications. And we have to decide ethically, in each society decide ethically, what such defect correction and imperfection correction would be allowed. I understand the arguments against allowing such modifications but I think that it should largely be left up to the individuals.