Here's what Lars says:
...there might be clarificatory work to be done concerning the significance of the expressions we use in reflecting on human attitudes and actions, even if we (sometimes) disagree on their application.If you're wondering exactly what 'significance' means here, the preceding paragraph helps:
...in ethical discourse the point of our remarks may often depend precisely on our disagreeing on the application of words; what holds our discourse together, on the other hand, is the degree to which, even so, we agree on the *significance* of a given description: *if* this were murder, *then*...So 'significance' means not quite meaning or importance but implication (which is related to both). And Lars's suggestion is that there might be clarificatory work to be done concerning the implications of the expressions we use in reflecting on human attitudes and actions. For example (if I understand correctly), if abortion really is murdering babies then this would suggest that abortion-providers deserve life in prison or possibly even the death penalty. And women who seek abortion would seem to deserve to be treated like people who try to hire contract killers. Some people (claim to) find such reasoning compelling, but for most people, I think, it is more like a reductio than an argument for rounding up large numbers of women and doctors. This kind of thing might lead those who say that abortion is murder to choose a different description, or to explain more carefully what they mean. This is the kind of work that Ronald Dworkin does (or tries to do on behalf of others) in Life's Dominion, and I think it can have great value.
'Significance' might also be taken as 'meaning,' so that we might inquire into, or try to clarify, the meaning of words like 'rights,' 'obligation,' and 'happiness.' I don't know whether Lars had that in mind, but I can see it being worthwhile. But given that we do so often disagree on the application of words like these I don't know where clarification would end and propaganda begin. Bentham's claim that talk of natural rights is nonsense on stilts strikes me as interestingly both conceptual analysis and political propaganda. Rightly or not, and interestingly or not, I think that Wittgenstein believed in avoiding this kind of thing. (Or did he? Was his desire to put a stop to all the claptrap about ethics not political in some sense, a desire to engage in a sort of culture war, or at least to bring about a cultural change?)
It's this entanglement of disagreement with (the most obviously) ethical concepts that makes philosophizing about them different from analyzing or clarifying uses of other kinds of words. But I suppose the difference is one of degree, so if I say you can't do Wittgensteinian work in ethics then the question arises where should we draw the line? I'd rather not make such a statement, but there is a problem here, I think, and I'd like to at least point it out or gesture toward it.