Darwinian Scepticism of Moral Intuitions
(For long-time readers, this version seems to me clearer than my previous attempts)
(1) Humans have trait X if, and only if, there is an evolutionary explanation for the presence of trait X.
(2) There is no evolutionary explanation as to why humans would make correct non-inferential moral judgements.
Conclusion:
(3) Humans do not make correct non-inferential moral judgements. (Less formally: Moral intuitions are unreliable)
Three key points to note:
(i) There's a large amount of biological evidence in favour of (b). The literature in biology does not explain the development of moral psychology by reference to awareness of moral facts. Given this independent evidence, (b) is not merely an assumption, nor does it beg the question.
(ii) The argument only concerns our non-inferential moral judgements. It is silent on our ability to reason towards correct moral judgement.
(iii) The argument applies only to our moral faculties because (b) does not hold true for our other traits. There are, for instance, very good reasons why human sight and logic would evolve to reflect the truth: they enable us to observe danger/food/mates/etc., and to reason about how to respond to these different situations appropriately. Again, the biology literature confirms this. For instance, explanations for the evolution of the human eye refer to how it would be advantageous to correctly observe the size/shape/distance/speed/colour/etc., of the objects around us.
Let X be the trait of
Let X be the trait of forming moral judgments according to criteria M. By (1), we have this trait iff there is an evolutionary explanation. Plausibly, there is such an explanation. So, plausibly, we do have this trait.
Now, there's an additional question whether M is the correct criteria for moral judgment. Maybe it is, maybe it isn't. Thus (2) is baseless. (You can show that we don't have an explanation of why we have X under the description of X's being the disposition to make correct moral judgments. But that leaves open the possibility that we have an explanation for the trait under some other description.)
Certainly the argument
Certainly the argument leaves open the possibility that there is some unknown evolutionary explanation of reliable moral intuitions.
But it's a question of burden of proof. If an evolutionary explanation needs to be provided in order to secure appeals to moral intuition, then, when such an explanation is lacking, we ought to eschew appeals to moral intuition.
Or have I misunderstood your point?
Al
Yes, my point was that we
Yes, my point was that we don't need an evolutionary explanation of our moral reliability per se. It merely needs to explain how we have the trait we do (which is easy). The hard work is then to explain whether the trait we have tracks ethical facts -- but that calls for moral theory, not evolutionary theory.
I'm a little concerned about
I'm a little concerned about both your premises. If we follow evolotionary theory do we have to believe that all traits are explained by it and only it? There are plenty of physical attributes that don't seem to be - though I'm certianly not an expert on this - I was thinking of left-handedness or different eye colour.
More seriously, I don't like your justification for 2. You note, 'The literature in biology does not explain the development of moral psychology by reference to awareness of moral facts.' Well it wouldn't, would it? It's written by scientists who are very unlikely to believe in the existence of such facts and certainly don't take them into account when writing their papers. Surely, it is up to philosophers and anthropologists to determine how the development of moral psychology took place not biologists?
It's easy to come up with examples of how acting morally would assist a group's survival and who's to say whether the individuals in that group are inferring or intuiting?
Hinton, I like these points,
Hinton,
I like these points, I shall give them further thought. But here's two replies that spring to mind:
You are quite right that it seems as though evolutionary explanations are not appropriate for all human traits. However, I suspect that the premise could be modified in minor ways to avoid this false implication. What springs to mind is that evolutionary explanations are necessary for all species-wide traits.
You're also correct that it seems as though the scientific method would be unlikely to posit moral facts. But if there is an evolutionary explanation for our moral intuitions that does not make reference to moral facts, then for there to be a second explanation of that same trait in terms of correct moral perception seems like unecessary over-determination.
But as I say, I must give these points further thought; these are tentative revisions.
Al