One should generally seek reasons as a defense from argument, not rationalization.
{Edit: My mistake, he really did mean emotivism and this paragraph kind of misses the point. Not going to delete, as it may confuse later comments.} More to the point, though, a refutation of emotivism is not a refutation of moral relativism, and, based on the little bit I could get off Amazon previews, relativism seems to be his problem, even if he wants to straw-man it as emotivism. Similarly, TGGP (given that he redundantly conjoins "I do not believe anything is good or bad in an objective sense" with "emotivism") seems to be more about the relativism than the emotivism specifically.
If that author actually manages to put a decent dent in moral relativism, please explain so I can go buy this book immediately, because I would be literally stunned to see such an argument.
Actually, based on this comment, TGGP actually believes in emotivism as such.
He isolates three reasons in the second chapter:
..."'Moral judgments express feelings or attitudes,' it is said. 'What kind of feelings or attitudes?' we ask. 'Feelings or attitudes of approval,' is the reply. 'What kind of approval?' we ask, perhaps remarking that approval is of many kinds. It is in answer to this question that every version of emotivism either remains silent or... becomes v
For a long time, I wanted to ask something. I was just thinking about it again when I saw that Alicorn has a post on a similar topic. So I decided to go ahead.
The question is: what is the difference between morally neutral stimulus responces and agony? What features must an animal, machine, program, alien, human fetus, molecule, or anime character have before you will say that if their utility meter is low, it needs to be raised. For example, if you wanted to know if lobsters suffer when they're cooked alive, what exactly are you asking?
On reflection, I'm actually asking two questions: what is a morally significant agent (MSA; is there an established term for this?) whose goals you would want to further; and having determined that, under what conditions would you consider it to be suffering, so that you would?
I think that an MSA would not be defined by one feature. So try to list several features, possibly assigning relative weights to each.
IIRC, I read a study that tried to determine if fish suffer by injecting them with toxins and observing whether their reactions are planned or entirely instinctive. (They found that there's a bit of planning among bony fish, but none among the cartilaginous.) I don't know why they had to actually hurt the fish, especially in a way that didn't leave much room for planning, if all they wanted to know was if the fish can plan. But that was their definition. You might also name introspection, remembering the pain after it's over...
This is the ultimate subjective question, so the only wrong answer is one that is never given. Speak, or be wrong. I will downvote any post you don't make.
BTW, I think the most important defining feature of an MSA is ability to kick people's asses. Very humanizing.