The general anti-abortionist line is that abortion is wrong because it is the killing of innocent people. The main pro-abortionist response to this has been to deny that what is killed in an abortion is, properly speaking, a person. Killing these things merely prevents another person from being added to the world, just as would contraception, except at a later stage in the total process; abortion is not, therefore, any kind of murder, any deprivation of a person's life. Kelly and Schedler now raise an interesting new question about this: suppose we do not kill the fetus, but merely painlessly prevent it from developing? This process they call ‘tinkering’. And they infer, from an apparently reasonable reconstruction of this standard pro-abortionist argument that “5′, Therefore, any non-viable fetus may be tinkered with”, and they affirm, “Presumably 5′ is morally repugnant”, (p. 123) And from this, in turn, they eventually infer that abortion itself is morally wrong, the argument being that there is no relevant difference between abortion and tinkering. This is an interesting argument. It is a good one? I will argue that it is not.