Why Properties Cannot Determine Personhood
Most if not all pro-choice philosophers try to cite certain properties which determine personhood such as consciousness or the capacity to experience pain or pleasure. There are some metaphysical objections to this that have been pointed out by David Oderberg, but there is one that is incredibly fundamental (see here: https://www.classicaltheism.com/unbornhuman/ ). The reason properties cannot determine personhood is because they depend on the substance and so cannot determine what the substance is. The only way to avoid this is to say that personhood is an accidental property, but this has its own problems, most notably numerous horrific ethical consequences to this view. However, there is, again, a more metaphysical problem with this view. It is fair to assume that personhood is that which confers rights on a certain entity, otherwise the personhood of the fetus would not be what grounds the fetus' right to life, as both pro-choice and pro-life philosophers grant. Oderberg point...