Close to one hundred people filled Carr Hall at St. Michael’s College this past Monday evening to see pro-life speaker Rebecca Kiessling’s presentation “Did I deserve the death penalty?” Kiessling was conceived in a rape, at a time before abortions were legal. Today, she uses the example of her own story to argue against abortion, even in the case of rape or incest.

“I am so thankful that my life was spared,” she gushed during her talk. And, later, “Whenever you identify yourself as pro-choice or make that exception for rape, [you’re saying to me], ‘I think your mother should have been able to abort you.'”

For Kiessling, the abortion debate is intensely personal. The greater part of her speech was devoted to a condensed story of her life, and of the influences that led her to become a lawyer, a mother, and a pro-life activist. It was clear that she had faced a great deal of hardship, including abusive boyfriends, social stigma about her adoption, and more. This personal connection to the issues lent her speech a great emotional weight. Her voice rose to a fever pitch as she told us, “My life matters, your life matters, don’t let anyone tell you differently!”

Unfortunately, the intellectual quality of the talk suffered because of the emotional focus. Her pro-choice straw men evoked cheap laughs from the audience-who were largely pro-life-while good philosophical arguments were notably lacking. Her response to Judith Jarvis Thomson’s famous “violinist analogy” (which argues that abortion is morally permissible) glossed over the analogy’s important points to criticize the particulars. And then, of course, there was the central fallacy: that she was in some way living proof that even children conceived during rape should not be aborted. Her response to the idea of abortion: “I’m not suicidal.”

The idea of equating abortion to murder stems from a curious metaphysical assumption: that in the tiny mass of cells there is the essence of a person. The fetus, say pro-life advocates, is not just what it is right now, but also everything that it can eventually become. Killing the fetus, then, amounts to denying the future adult its right to live. Pro-choice advocates counter that this reasoning is absurd-why should we call the fetus a person months before it has any of the characteristics of a human?

The pro-choice argument is reminiscent of a Zen koan: “What is your original face before you were born?” Like all koans, there is no straight answer. Rather, the goal is to recognize the absurdity of the question. The koan invites you to seek the essence of your person until, exhausted by the effort, you realize that there is no essence, only a constant flux of thought, emotion, and experience. What, then, can we say about a “person” who has neither thought nor emotion nor experience? Surely that is no person at all.

If the pro-choice argument brings to mind the idea of Zen Buddhism, the pro-life argument is based on the assumptions of Christianity, especially Catholicism, and specifically on the doctrine of the eternal soul. This is the lynchpin of the pro-life argument: that Rebecca Kiessling as an embryo is Rebecca Kiessling as an adult, because the soul, or essence, is the same.

This is a thorny dichotomy. It can be attacked philosophically, but philosophical discourse is far removed from the majority of abortion debates. And since the metaphysical question is so fundamental, neither side is likely to ever change their mind. The only way forward, then, is for one side to attack the other within its own metaphysical framework. Thomson’s violinist, for example, attempts to demonstrate that even if the fetus is a person, the mother should still have the right to abort.

I have seen no substantial arguments of this sort from the pro-life side, suggesting that the case against abortion truly does rest on an essentially Christian worldview. If this is the case, then the pro-life contingent may be doomed to eventual failure.