Last Friday, April 30, I attended a debate at the University of Minnesota between two prolific philosophers, Peter Kreeft and David Boonin, on the ethics of abortion. Kreeft is a philosophy professor at Boston College and the author of many books including "The Unaborted Socrates" and "Three Approaches to Abortion." Boonin is a philosophy professor at the University of Colorado and the author of "A Defense of Abortion," which is probably the best comprehensive philosophical defense of abortion. Kreeft and Boonin have debated each other before, at Yale University and at the University of Colorado.
Kreeft offered a basic, three-premise pro-life argument. First, a moral or philosophical premise: all human beings have a right to life. Second, a scientific premise: the unborn is a human being. Third, a legal premise: the law should protect fundamental human rights, such as the right to life. From these three points, it follows that killing unborn human beings by abortion is wrong and should be prohibited. You can read Kreeft's excellent case in online essays here and here.
Kreeft added a final argument from uncertainty: If we are still uncertain whether the unborn is a human being with a right to life, then it only makes sense that we should oppose abortion. I've discussed this argument here.
Boonin -- who I should mention was kind, gracious, articulate and extremely intelligent, perhaps the best abortion defender out there -- surprised me by conceding, from the outset, Kreeft's three premises. In other words, he assumed, for the sake of argument, that the unborn is a valuable human being with a right to life, but then argued that abortion in most cases is still morally permissible. I've called this the sophisticated argument from bodily autonomy. (Boonin makes this argument in his book, but he also argues at length that the unborn throughout most of pregnancy does not have a right to life. It is interesting that in the debate he opted to focus solely on the former argument.)
Here's how he summarized the key claim, which he defended using a thought experiment supposedly analogous to an unwanted pregnancy: "The right to life is not the same as the right to be kept alive by another person." So, while the unborn may have a right to life, that right does not entail a right to use the pregnant woman's body as a life support system. So "disconnecting" the unborn by abortion is permissible.
I think philosopher Francis Beckwith, in "Defending Life" (p. 172-199), does the best job of tackling Boonin's specific version of this argument in detail and showing why it doesn't work to justify abortion. I've addressed the general argument myself here, and you can read some of Beckwith's critique here (start at p. 189).
What struck me in the debate is that Boonin conceded a moral difference between active killing and witholding care, and seemed to agree that his argument would only justify abortion methods that do the latter. He pointed to hysterotomy as an example. But hysterotomy abortion, as far as I know, is incredibly rare, practically nonexistent. The main first trimester abortion method, suction curettage, and the main second trimester method, dilation and evacuation, are both clear examples of active killing. It seems that, by Boonin's own admission, his argument, even if it worked, would not justify the vast majority of abortions.
Boonin acknowledged that the debate over abortion has largely turned (rightly, in my view) on the moral status of the unborn, which his argument attempted to sidestep. And he acknowledged that his embrace of the argument is a minority position, one even rejected by many fellow pro-choice philosophers (who argue for the permissibility of abortion on other grounds, focusing on the status of the unborn).
I don't see his argument ever really catching on, and not just because it's abstract and uses weird analogies, but because it's radically contrary to our basic intuitions about the nature of pregnancy and the parent-child relationship.