lukeprog gave a list of metaethics questions here:
What does moral language mean? Do moral facts exist? If so, what are they like, and are they reducible to natural facts? How can we know whether moral judgments are true or false? Is there a connection between making a moral judgment and being motivated to abide by it? Are moral judgments objective or subjective, relative or absolute? Does it make sense to talk about moral progress?
Most of these questions make no sense to me. I imagine that the moral intuitions in my brain come from a special black box within it, a "morality core" whose outputs I cannot easily change. (Explaining how my "morality core" ended up a certain way is a task for evo psych, not philosophy.) Or I can be more enlightened and adopt Nesov's idea that the "morality core" doesn't exist as a unified device, only as an umbrella name for all the diverse "reasons for action" that my brain can fire. Either perspective can be implemented as a computer program pretty easily, so I don't feel there's any philosophical mystery left over. All we have is factual questions about how people's "morality cores" vary in time and from person to person, how compelling their voices are, finding patterns in their outputs, etc. Can someone explain what problem metaethics is supposed to solve?
You may establish a formal system of morality, make up some requirements (say, no theorem which starts with "you ought to prefer" is produced within the system), and if you were lucky with the inference rules and axioms, then you would see that your morality works (e.g. no matter how hard you try, you can't derive "you ought to prefer killing kittens"). Clearly, that doesn't mean that the selected system of morality has the same status as logic.
The important question is, why non-occurence of contradictions is believed to be important for logic to work? Why even have a negation sign in our symbolic alphabet of logic? Without that, a contradiction couldn't be even defined. The only answer I can think of is that logic is extremely strongly and universally supported by intuitions, or, if you want, by the brain architecture. Moral intuitions are more complex and variable.
The point was that we have reason why we don't want contradictions: we want our inferences to be correct. So logic is instrumental there. Morality on the other hand seems to be something we wish to be a certain way, for its own sake.
Modus ponens works better than appeal to inappropriate authority wrt. making correct inferences. In the case of morality, what works better than what wrt. doing what?
You could ask why we would want correct inferences. But I don't see a point in reducing further.
The analogy to morality would make sense if say we already made up ... (read more)