But if you discard every procedure that evolution gave you and all its products, then you discard your whole brain. You discard everything that could potentially recognize morality when it sees it. You discard everything that could potentially respond to moral arguments by updating your morality. You even unwind past the unwinder: you discard the intuitions underlying your conclusion that you can’t trust evolution to be moral. It is your existing moral intuitions that tell you that evolution doesn’t seem like a very good source of morality. What, then, will the words “right” and “should” and “better” even mean?
So we have to know something about morality in order to engage in moral arguments. If literally all of our moral intuitions were “false”, we couldn’t even update in the right direction. It would be a completely hopeless endeavor just like creatures with Anti-Occamian priors are epistemologically doomed (in our universe).
…Could there be some morality, some given rightness or wrongness, that human beings do not perceive, do not want to perceive, will not see any appealing moral argument for adopting, nor any moral argument for adopting a procedure that adopts it, etcetera? Could there be a morality, and ourselves utterly outside its frame of reference? But then what makes this thing morality—rather than a stone tablet somewhere with the words ‘Thou shalt murder’ written on them, with absolutely no justification offered?
So all this suggests that you should be willing to accept that you might know a little about morality. Nothing unquestionable, perhaps, but an initial state with which to start questioning yourself. Baked into your brain but not explicitly known to you, perhaps; but still, that which your brain would recognize as right is what you are talking about. You will accept at least enough of the way you respond to moral arguments as a starting point, to identify “morality” as something to think about.
Right, but which moral intuitions should you trust? Which preferences of which brain modules should you accept and which should you ignore?