All this relativism talk. Velleman posts on relativism because he isn't satisfied with what he sees. Me neither, even after reading Velleman. Allow me to ruminate.
The correct thing to say about relativism is that some version of relativism is true, and the correct thing to say about absolutism is that every version of absolutism is false. If you don't think there is a BOOK OF RULES from the transcendent PLANE OF MORAL TRUTH, then you're likely some sort of relativist. And that's OK. Don't worry.
Velleman's use of “agent-relativism” is confusing. Generally agent-relative is contrasted with agent-neutral with respect to value or reasons for action. My reason to get a drink of water is agent-relative, because its MY thirst. My reason to go to dentist school is agent-relative because being a dentist is MY goal. Etc. Whether or not there are agent-neutral reasons, reasons not based in our individual aims, reasons we just have because we're rational agents, or what have you, is a tricky question. (The answer is yes and no. You can have a reason to do something that is independent of your particular aims and projects. Your reason not to murder me is not agent-relative in the way your reason to go to scuba classes is. But agent-neutral reasons don't get off the ground without the enterprise of coordinating agent-relative reasons.) Anyway, if you are sane, you are an agent-relativist in the sense that you believe there are agent-relative reasons. Some thing really are right for me and wrong for you, because you and I want different things.
Any non-transcendent moral standard is relative to SOMETHING, isn't it. Aristotle, for example, is a species-relativist. What is right for me to do is relative to what natural kind I'm an instance of. In updated terms, you can be a genomic relativist. The right thing to do is relative to your genome. This is not, however, any kind of transcendent standard. The human genome, say, is a contingent kludge. Evolution could have taken a left and that species (not us) would have a different genome, and a different moral standard based in their “nature.” So, yes, if you believe in SCIENCE and believe in a human nature-based morality, then you're a kind of relativist. But that's not so scary, is it?
Utilitarians may seem like absolutists. But the right thing to do for a utilitarian is relative to contingent empirical facts about what does and doesn't cause pleasure in sentient beings. (Am I just playing with words?)
The Pope I suppose, is worried more about cultural relativism. Cultural relativism is a little bit true, though. Being a member of one culture rather than another can give you a reason to do something that you wouldn't otherwise have. There ARE culturally relative reasons. Is it morally OK to impale kittens on pikes because your culture says so? Probably not. To kill your sister if she is accused of whoreishness? No. Does anybody think so? (People who think its OK to kill their allegedly whoring sister don't think its OK because its THEIR culture that says so. They think its OK because that's what they think the transcendent BOOK OF RULES says.)
Actually, I don't have any idea what the Pope is talking about. It actually sounds like he's sort of longing for the days of moral hegemony that died with Luther, and confusing pluralism for relativism.
Anyway, here are some things my reasons are relative to: my genome; my capacity for sympathy and moral imagination; my personal goals and projects; my social and family commitments; other parochial allegiances; the conventional terms of social cooperation where I live; lots more. And yours too!
I meant to say something usefully clarificatory, but oh well. Coherence will return in future posts.