Case 2: All the evidence at Jill's disposal indicates (in keeping with the facts) that giving John Drug B would cure him partially and giving him no drug would render him permanently incurable, but it also indicates (in contrast with the facts) that giving him drug C would cure him completely and giving him drug A would kill him.
Suppose that on the basis of the evidence, Jill gives drug C and kills John. Zimmerman's prospective view implies that Jill did what she ought to but the objective view implies that she did not. Someone like Moore would say that although Jill acted wrongly but she is not to blame for doing so.
Some will say that this response just isn't satisfactory, but making matters worse is this:
Case 3: All the evidence at Jill's disposal indicates (in keeping with the facts) that giving John Drug B would cure him partially and giving him no drug would render him permanently incurable, but her evidence leaves it completely open whether it is giving him Drug A or Drug C that will kill him or cure him.
Zimmerman says (paraphrase) that if we put Moore in Jill's shoes in Case 2, he could say, "Unfortunately, it turns out that what I did was wrong. However, since I was trying to do what was best for John, and all the evidence at the time indicated that that was indeed what I was doing, I cannot be blamed for what I did" (18). He cannot say this in Case 3, however, because the conscientious person would knowingly do what would not be the best.
I think there are two things the objectivist might say in response. First, the objectivist might offer a sort of tu quoque. Zimmerman stresses that it can be exceptionally difficult to determine which actions will maximize expectable value and so I think he'd acknowledge that someone can have reasonable but mistaken beliefs about which acts will maximize expectable value. I don't see why cannot construct cases where an agent knows that the action that will maximize expectable value is either A or C, not know which of these options will be the one that maximizes expectable value, know that A or C (but not which one) will be the worst from the point of view of maximizing expectable value, and know that B is somewhere in between these two options.
Second, it seems that Zimmerman is assuming that the conscientious person will not do what they believe to be overall wrong. Can't the objectivist deny this? It might seem a desperate maneuver, but if that's a move that everyone has to make, we should all lump it.
Zimmerman anticipates a version of this response, and here's what he says:
One response that might be made on behalf of the Objective View is this. It is true that, if Moore were put in Kill's place in Case 3, as a conscientious person he would choose to give John Drug B. But the choice would be perectly in keeping with his adherence to the Objective View, for it would simply constitute an attempt on his part to minimize the risk of doing wrong (20)
This response is unacceptable. I have stipulated ... that the probability that giving John Drug B will cure him only partially is 1. From the prospective of the Objective View, then, the probability that giving him this drug is wrong is 1, whereas, for each of drugs A and C, the probability that giving him the drug is wrong is less than 1. Hence, according to the Objective View, giving John Drug B does not minimize the risk of doing wrong; only the contrary, it is guaranteed to be wrong (20).
Darn, good point. Why can't the objectivist say that the agent will minimize the risk of _harm_ or _negative value_ rather than wrongdoing? I think the idea is that the conscientious agent always acts on judgments about what's right or wrong rather than what's good/bad, but if denying that the conscientious agent never decides to do what he knows he oughtn't, this seems like a good fallback position.
So, a lot of this will depend upon whether there are variants of Case 2 and 3 that cause trouble for the prospectivist, but if there are, the response I'm imagining the objectivist could use could be used by the prospectivist as well. But, that does mean that the force of Case 2 and 3 has effectively been neutralized. I need to look at Zimmerman's remarks concerning determinate levels of evidence to see if he has a way of dealing with this.