- Frank J. Leavitt, Ph.D.
The Jakobovits Centre of Jewish Medical Ethics
Faculty of Health Sciences, Ben Gurion University of the Negev, Beer Sheva, ISRAEL (Home Tel/FAX: +972-2-9963048)
All of these criteria are totally personal taste. Tooley, for example, apparently prefers those who can "envisage a future", and declares that those who cannot envisage a future are non persons. Another philosopher might, instead prefer those who agree with this philosopher's choice of whisky. Whoever doesn't like this brand of whisky would be a non-person whom one might kill if one pleases. It's all a matter of which criteria the philosopher happens to like.
Of course I'm joking when I use the example of choice of whisky. But I want to emphasize a point. As soon as you lay down a substantive criterion for personhood you are assuming you have a right to play God, decreeing who is good enough to live and who isn't. And your decree can only be based on your personal preferences.
Nor do I think "having a soul" is a good criterion. The author thinks that all monotheistic religions accepted Aristotle's doctrine of the soul. But this is not true. Judaism does not even require that you believe in the existence of the soul. There is a Jewish belief in the revival of the dead. But God could do this without souls if He wanted to, by simple recreating bodies.
In Jewish mysticism, Kabala, there is a belief in soul, but not in soul as Aristotle saw it. There is not one unified soul, but soul consists of many parts, spiritual "sparks", which can exist together or apart from one another. This seems more consistent than is Aristotle with current views in neurobiology according to which there is no one central focus of consciousness. It also seems consistent with such phenomena as split personalities, inner struggles, disorientation, etc. Of course Maimonides was an Aristotelian and accepted Aristotle's doctrine of the soul for the most part. But many rabbis rejected both Aristotle and Maimonides. In my own opinion there is only one criterion for personhood: being born of woman. This is a non-substantive definition, independent of the criteria we think up. If you have or had a mother then you are a person, and have all the rights of a person. And it doesn't matter whether I can or cannot communicate with you, or like you or find you disgusting.
I must admit however that my non-substantive definition has one difficulty. Suppose that someday embryos will be developed into viable babies without benefit of womb. Would these babies be people or not? I think they would be, but this makes a difficulty for my criterion, and I'm not sure how to solve it.