My initial position was in favor of the pro-choice position. In particular, I contended with the notion that a fetus could properly be described as "innocent." My argument was that "innocence" assumes some form of moral accountability, such that if something cannot be morally responsible for its actions, then it cannot meaningfully be called innocent. I used a rock as an analogy: a rock is neither guilty nor innocent because it has no capacity to be morally accountable. I argued that a fetus, insofar as it likewise lacks moral accountability, should be understood in the same way.
Although this point was successful in the debate at the time, I no longer agree with my argument. I believe I failed to distinguish between moral neutrality and moral innocence, as well as between the absence of possible moral agency and having an inherent potential for moral agency.
The rock analogy appeared persuasive because both a rock and a fetus lack actual moral accountability. However, this similarity is insufficient to establish that they have the same moral status. A rock isn't morally innocent because it isn't the kind of entity that can develop moral agency. Its lack of accountability follows from its nature: there is no inherent developmental trajectory by which a rock becomes a rational or morally responsible subject. The rock is therefore amoral.
On the contrary, a fetus, despite not presently possessing the rational and moral characteristics of an adult human, belongs to a human nature whose developmental trajectory includes those characteristics and capacities.
A big mistake I made was equivocating extrinsic and intrinsic potential. I made the generalization that potentiality isn't an intrinsic property, but this is not enough to dismiss the fetus's moral significance. My point was along the lines of: "If you have divine knowledge that I'll rob a bank in ten years, it'd be wrong of you to arrest me today because that future experience is not inherent to who I am presently." This would be relational and it is not analogous to the capacity I have to grow.
The difference is that my future act of robbing a bank is merely something I may contingently do. It is not a capacity that belongs to me by virtue of my nature. The fact that someone knows I will do it does not make the act an intrinsic part of what I am. My capacity to grow, however, is different. It belongs to me by virtue of the kind of being I am.
This is the distinction I failed to make. Extrinsic potential concerns what something can become through some external relation or intervention, while intrinsic potential concerns what something can develop into by virtue of its own nature. A block of marble can potentially become a statue, but that potential depends upon something external shaping it. An acorn, however, has an intrinsic potential to become an oak because its development is grounded in what the acorn itself is. The fetus is relevantly analogous to the latter. Its capacity to develop rationality is not something arbitrarily imposed upon it from the outside. Rather, it is part of the natural development of the kind of being it is. The fetus does not merely have the possibility of becoming rational; it possesses an intrinsic developmental capacity for rationality.
This also changes how I understand actual and potential moral agency. A fetus does not presently possess moral agency in the same sense that an adult does. It cannot deliberate about moral reasons, make moral judgments, or be held responsible for its actions. In this respect, it is genuinely pre-moral. But being pre-moral is not the same as being amoral. An amoral thing, such as a rock, is outside the domain of moral agency altogether. A fetus is instead a being whose relevant capacities have not yet been actualized. Its lack of present moral accountability therefore does not establish that it is morally neutral in the same sense as a rock.
This is where my original understanding of innocence becomes important. I treated innocence as though it required presently actualized moral agency: if something cannot be morally accountable, I reasoned, then it cannot be innocent. But this conflates the capacity for culpability with culpability itself. A being can lack present moral agency while still being innocent in the sense that it is not guilty of any wrongdoing.
A rock cannot meaningfully be called innocent because it cannot meaningfully be guilty either. It is simply outside the moral domain. A fetus is different because its present inability to exercise moral agency is a developmental condition rather than a consequence of belonging to a fundamentally non-moral kind. Therefore, I would now describe the fetus as pre-moral rather than amoral. It is not morally accountable, but neither is it morally irrelevant. Its intrinsic potential for rational and moral agency distinguishes it from things that are incapable of entering the moral domain altogether.
My original argument succeeded in the debate because it pointed to the fact that a fetus does not presently possess moral accountability. What I failed to recognize was that this fact alone does not establish amorality. The fetus and the rock share an absence of present moral accountability, but they do not share the same kind of absence. The rock lacks moral agency by its nature; the fetus lacks it because its relevant capacities have not yet been actualized.
Thus, I would now revise my original position: a fetus is innocent, not because it presently exercises moral agency and deliberates an avoidance of wrongdoing, but because it is of the human nature and still not culpable for any wrongdoings. Its pre-moral condition does not make it amoral, because its inherent potential distinguishes it from beings that are outside the domain of moral capacity altogether.