Full Idea
We allow that abortion is permissible in many circumstances, but infanticide is hardly ever permissible, and yet it is hard to justify this disparity in moral judgement in the sense of finding the relevant difference.
Gist of Idea
It is hard to justify the huge difference in our judgements of abortion and infanticide
Source
Frank Jackson (From Metaphysics to Ethics [1998], Ch.5)
Book Reference
Jackson,Frank: 'From Metaphysics to Ethics' [OUP 2000], p.134
A Reaction
The implications of this are tough to face. A foetus is (maybe) just not as important as a new-born babe - and so a new-born babe is of less importance than a five-year old. Birth is (or was) a hugely dangerous hurdle to be cleared.