I just realized that linguists have been using a concept of deontic modality to express various degrees of “ought”, “may”, “can”, and the like. This is interesting in a couple of ways.
Brandom often talks about a pair consisting of deontic normative and alethic modal things, while sometimes suggesting that truth is actually subordinate to normativity. “Alethic modality” is the phrase used by the linguists to express modalities of truth. I’m not sure why Brandom chose not to similarly adopt the linguists’ exact phrase for the deontic one (perhaps to save “modal” for its standard, hyperstrong logical sense), but it is certainly interesting to note that the linguists see the deontic one as also modal.
It is also very interesting to see that the linguists apparently see deontic modality as expressed in terms of degrees, which seems eminently reasonable. I tend to see deontological ethics as promoting untenably unconditional ground-level requirements, so this is a welcome relief. (See also Necessity in Normativity; Binding; Evaluation of Actions; Modality.)