[Part of The Molyneux Project; read the main critique here]
I won't dwell on Stefan's discussion in his section on "Gray Areas," except to note that he belies a complete lack of knowledge about the things he's talking about. Philosophy of biology is a thriving and interesting field, and if Stefan wants to criticize people who hold certain views, he should first find out why they hold them. As it stands, he regrettably ends up sounding like one of the countless bitter pseudo-intellectuals who think that mainstream philosophy is stupid because philosophers hold positions that sound obviously counterintuitive to people who don't understand what they actually are, or why they should be believed. I think Stefan's better than that, and I wish he wouldn't give me reason to doubt that opinion.
In the next section, on page 56, Stefan asserts that "Clearly" the statement that "There are no such things as gray areas" can be "easily discarded," and thereby concludes that certain gray areas do exist. I don't want to dwell on this, but some people might say that gray areas don't actually exist, but language is often imprecise, and knowledge is often incomplete, leading to the usefulness of accepting the concept of gray areas. Either way, most people are relatively comfortable with the idea that some ideas cannot be (or sometimes are not) expressed with perfect precision, and that this shouldn't lead us to reject a statement as being false.
But I just wanted to point out in passing that Stefan's examples make no sense. He writes, "...certain gray areas do exist, and we know that they are gray relative to the areas that are not gray." So far so good. He continues, "Oxygen exists in space, and also underwater, but not in a form or quantity that human beings can consume." Still okay. "The degree of oxygenation is a gray area, i.e. "less versus more"; the question of whether or not human beings can breathe water is surely black and white." Huh? What does that even mean?
The next example: "A scientist captured by cannibals may pretend to be a witch-doctor in order to escape - this does not mean that we must dismiss the scientific method as entirely invalid." Again, huh? The scientific method is useful for working towards knowledge. A scientist captured by cannibals wouldn't be pursuing knowledge when she acted like a witch-doctor, and (as Stefan seems to imply) the scientific method would be an awful tool for escaping from murderous cannibals. How does this have anything to do with gray areas?
Then Stefan makes a pretty big mistake. He writes, "Similarly, there can be extreme situations wherein we may choose to commit immoral actions, but such situations do not invalidate the science of morality, any more than occasional mutations invalidate the science of biology." This is plainly an unsubstantiated claim. Biology doesn't claim to make incontrovertible claims about animals. According to Stefan, universally preferable behavior identifies behavior which everyone should engage in. Otherwise, he would simply have to say that there is no universally preferable behavior for the kind of situation in question. If biology made the kinds of claims that Stefan makes about universally preferable behavior, then it would be "invalidated" by occasional mutations. The science of biology survives because it doesn't make the kinds of claims that Stefan is making. Biology can't define a species in a strict manner for precisely that reason. And biologists don't. Since Stefan is defining morality in a strict manner, he's helping himself to some wiggle room that he has no right to.
Stefan's conclusion, incidentally, is correct. But I'm not sure how he arrives at it. He writes, "In fact, the science of biology is greatly advanced through the acceptance and examination of mutations - and similarly, the science of ethics is only strengthened through an examination of "lifeboat scenarios," as long as such an examination is not pursued obsessively." It's true that ethical theories are improved by taking "lifeboat scenarios" into account. But if morals are supposed to identify universally preferable behaviors, then it's clear that moral theories must be changed in order to take account of these scenarios. That is, Stefan is running into problems because he insists on calling the reactions in lifeboat scenarios "immoral." If he thinks that we should commit these actions, then he cannot call them immoral. And if he thinks that we shouldn't, then he'll need to offer the kind of explanation I discussed in my last post.
I'm going to pause here before moving into the next section, "Universality and Exceptions," because I have a funny feeling that it's going to take a while.