There’s a longstanding dispute about whether psychopaths are morally responsible. For our purposes, just stipulate that psychopaths are blind to moral reasons, that is, they lack moral, or normative, competence. There’s not much disagreement on this point (for psychopaths who score very highly on the Hare Checklist). The disagreement, instead, is over whether normative competence is necessary for moral responsibility. Suppose a psychopath sees that hitting you with a baseball bat will cause you pain, but he does it anyway because it’s fun. So, it’s thought, he judges hitting you to be worth doing, and he also judges that your interests don’t matter. Isn’t that sufficient to ground apt moral blame, and so sufficient for his being morally responsible?
Or so a school of thought goes (represented by Tim Scanlon, Angela Smith, Matt Talbert, and Pamela Hieronymi). What matters is that the psychopath at least has the rational capacity to form judgments of worth, i.e., make evaluative judgments of reasons. If he does, then it doesn’t matter if he’s blind to one subset of reasons; he’s still blameworthy for judging that the bad thing is worth doing and judging that other considerations don’t matter.
I want to try out an argument against this stance and see what you think.