Why Jonas Olson Cannot Believe the Error Theory Either

Jonas Olson writes that “a plausible moral error theory must be an error theory about all irreducible normativity”. I agree. But unlike Olson, I think we cannot believe this error theory. In this symposium contribution, I first argue that Olson should say that reasons for belief are irreducibly normative. I then argue that if reasons for belief are irreducibly normative, we cannot believe an error theory about all irreducible normativity. I then explain why I think Olson's objections to this argument fail. I end by showing that Olson cannot defend his view as a partly revisionary alternative to an error theory about all irreducible normativity.