Why have teachers of philosophy taken up this obvious piece of specious sophistry? I suppose it is a device to engage the interest of their charges.
David Benatar’s baby is like Schrodinger’s cat both dead and alive. For the purposes of pain he/she is alive and for the purposes of pleasure not alive. For various complex reasons D.B. urges that it would be the moral thing if the baby never was, never came into existence and never was allowed to be born if through some oversight it was conceived. Now my point is this and it’s a very simple one - how can something which doesn’t exist, which is a generalised abstract non-entity be weighed on any moral balance against any other entity, fish, flesh or good red herring.
His general thesis is one which he extrapolates from the particular thesis of the known suffering of a child that would likely be born with a serious genetic defect. The idea is that one would not consider it correct to conceive and give birth to a child that would suffer throughout a short life. To go from that case which warrants serious consideration to a general reluctance to conceive is just too big a step. You have gone from a specific definite case in which the potential harm are clear to a hypothetical unestablished abstract generalised harm. This supposed harm can simply be countered by saying what very many people would say with complete sincerity - on balance I am happy to be alive and I am glad that I was born. Here’s the great speech from Blade Runner. Even a replicant is glad to have lived.
Roy: I've seen things you people wouldn't believe. Attack ships on fire off the shoulder of Orion. I've watched C-beams glitter in the dark near the Tannhauser Gate. All those moments will be lost in time, like tears in rain. Time to die.