[einhverfr]

> Given these principles, at what point in existence does one qualify as having human rights and on what basis do we identify that point?

That's an important piece of the argument. Is personhood innate (in which case it must begin at conception, sicne there are no other bright lines in development that make universal sense across culture and time)? Or is it a social construct (in which case we have no right to see abortion as different from Roman infanticide)?

In other words, is personhood and human rights innate, in which case you must be a pro-life extremist if you are willing to seriously argue that? Or is personhood socially recognized and constructed, in which case you must accept that abortion is infanticide but also that infanticide is ok if the culture says so? The thing is both of these are relatively extreme viewpoints. Very few on the right want abortion to be punished the same as infanticide, and very few on the left are willing to acknowledge that if abortion is ok, then infanticide must be too (but there are some, see NARAL and Planned Parenthood's defence of killing fetuses born alive after failed late-term abortions).

> In establishing the criteria for human life, we should consider as many implications as possible.

Doesn't that mean we should leave it up to local cultures to sort this out for themselves? If Rome wants to mandate infanticide in the case of severe birth defects, bully for them.