Procreative beneficence: cui bono?

Recently, Julian Savulescu and Guy Kahane have defended the Principle of Procreative Beneficence (PB), according to which prospective parents ought to select children with the view that their future child has 'the best chance of the best life'. I argue that the arguments Savulescu and Kahane adduce in favour of PB equally well support what I call the Principle of General Procreative Beneficence (GPB). GPB states that couples ought to select children in view of maximizing the overall expected value in the world, not just the welfare of their future child. I further argue that Savulescu and Kahane's claim that PB has significantly more weight than competing moral principles, such as GPB, lacks justification. A possible argument for PB having significant weight builds on a principle of parental partiality towards one's own children. But this principle does not support PB; it supports a Principle of Sibling-Oriented Procreative Beneficence (SPB), according to which parents selecting a child should maximize the benefit of all their children. Indeed, PB itself will in some cases be self-effacing in favour of SPB.