Momentary Language

Some enchanted evening ... you will meet a very large stranger

Peter Singer has a new post, over at Project Syndicate, on the question, "Should We Trust Our Intuitions." In it, he refers to recent work in experimental philosophy by Josh Greene and Marc Hauser, both at Harvard.

There's an old chestnut in moral psychology known as the "trolley problem." Here's Singer's description:

In one dilemma, you are standing by a railroad track when you notice that a trolley, with no one aboard, is heading for a group of five people. They will all be killed if the trolley continues on its current track.

The only thing you can do to prevent these five deaths is to throw a switch that will divert the trolley onto a side track, where it will kill only one person. When asked what you should do in these circumstances, most people say that you should divert the trolley onto the side track, thus saving a net four lives.

In another dilemma, the trolley, as before, is about to kill five people. This time, however, you are not standing near the track, but on a footbridge above the track. You cannot divert the trolley. You consider jumping off the bridge, in front of the trolley, thus sacrificing yourself to save the five people in danger, but you realize that you are far too light to stop the trolley.

Standing next to you, however, is a very large stranger. The only way you can prevent the trolley from killing five people is by pushing this large stranger off the footbridge, in front of the trolley. If you push the stranger off, he will be killed, but you will save the other five. When asked what you should do in these circumstances, most people say that it would be wrong to push the stranger.

Standard apriorist philosophy often seeks to provide a theoretical underpinning to validate our intuitions -- that is, to provide a deeper explanation for why it is right to flip the switch but not to push the stranger onto the track. Greene and Hauser, however, are using research techniques from social psychology and neuroscience to provide a naturalistic explanation for our intuitions. Again, here's Singer:

Greene found that people asked to make a moral judgment about “personal” violations, like pushing the stranger off the footbridge, showed increased activity in areas of the brain associated with the emotions. This was not the case with people asked to make judgments about relatively “impersonal” violations like throwing a switch. Moreover, the minority of subjects who did consider that it would be right to push the stranger off the footbridge took longer to reach this judgment than those who said that doing so would be wrong.

Why would our judgments, and our emotions, vary in this way? For most of our evolutionary history, human beings – and our primate ancestors – have lived in small groups, in which violence could be inflicted only in an up-close and personal way, by hitting, pushing, strangling, or using a stick or stone as a club.

To deal with such situations, we developed immediate, emotionally based intuitive responses to the infliction of personal violence on others. The thought of pushing the stranger off the footbridge elicits these responses. On the other hand, it is only in the last couple of centuries – not long enough to have any evolutionary significance – that we have been able to harm anyone by throwing a switch that diverts a train. Hence the thought of doing it does not elicit the same emotional response as pushing someone off a bridge.

The lesson that Singer draws from this research is that

these findings should make us more skeptical about relying on our intuitions. There is, after all, no ethical significance in the fact that one method of harming others has existed for most of our evolutionary history, and the other is relatively new. ... And surely the death of one person is a lesser tragedy than the death of five, no matter how that death is brought about. So we should think for ourselves, not just listen to our intuitions.

I'm not as certain as Singer that, as a general rule, the evidence provided by our emotional responses to actual events or potential situations ought to be considered to be misleading as to whether it would be appropriate to bring about or prevent those events or situations. If Singer's evolutionary explanation of the particular responses to the trolley problem were correct, however, it would seem plausible to me that, in this case, the intuitions in question ought to be questioned -- as Singer says, "there is, after all, no ethical significance in the fact that one method of harming others has existed for most of our evolutionary history, and the other is relatively new."

I doubt, however, that the "personal"/"impersonal" explanation for the differing responses to the two cases is correct. Here's why. Suppose that one altered the second case so that, instead of pushing the large stranger off of the footbridge, you were removed from the situation, with access only to a switch that would allow you to move a crane so that the large stranger would be pushed off of the footbridge onto the track in the path of the oncoming trolley.

This, presumably, would make the second situation just as "impersonal," according to Greene's dichotomy, as the first situation. Nevertheless, my sense is that people would feel just as uncomfortable about pushing the large stranger off of the footbridge by flipping the switch and moving the crane as they would about "personally" pushing the large stranger off of the footbridge. If my hunch about this is correct, it would seem that the explanation of our intuitions in the trolley case has to appeal to something a bit more involved than the personal/impersonal dichotomy, at least as portrayed by Singer.

Expressivism and the Fine-grainedness of Attitudes

Since an upper-level epistemology seminar at a liberal arts college would achieve an enrollment of under 3, I decided to work through Russ Shafer-Landau's Moral Realism: A Defence with my students. I'll be posting random thoughts/criticisms related to that book here, as they present themselves to me.

This first criticism may not be entirely fair, since Shafer-Landau merely reviews criticisms of expressivism that he finds promising, without fleshing them out in great detail. Nevertheless, I found his confidence in the following criticism puzzling. He writes:

If expressivism is true, the essence of any moral statement is the expression of a fundamentally non-representational attitude towards some natural state of affairs. If, as it seems, we convey and mean something slightly different when we say of an action that it is virtuous, right, mandatory, supererogatory, kind, ... then non-cognitivists must explain this by citing a different attitude that receives expression in each case. But our attitudes don't seem nearly as diverse or fine-grained as the predicates we standardly employ in moral assessment. Cognitivists straightforwardly account for these differences by referring to different meanings, contents, or properties that are exemplified when these different assessments are true. Expressivists must either deny that these predicates signify different assessments, or identify a different attitude for each predicate. Neither route seems very promising. (25)

So Shafer-Landau sets up a dilemma for the expressivist here: either (a) moral predicates, despite appearances, in fact signify very few discrete assessments or (b) each distinct moral predicate corresponds to an equally distinct attitude.

I see the problem with (a). However, I don't see why the expressivist shouldn't embrace horn (b) of the dilemma wholeheartedly. Shafer-Landau suggests that the fine-grainedness of our moral predicates poses no difficulty for the cognitivist because the cognitivist can simply refer to the different "meanings, contents, or properties" exemplified when the assessments containing those predicates are true. That is, "is saintly" picks out the property of saintliness. Fine. However, while it's certainly clear that expressivists can't appeal to property talk, it is utterly mysterious why they can't say that the use of "is saintly" expresses the attitude corresponding to that predicate.

The point is this. If, as the expressivist claims, it is the case that the use of moral predicates derives its force from the attitudes to which they give expression, there is no reason why the expressivist can't claim that the multitude of distinctions contained within the moral predicates is not simply proof of the fine-grainedness of the attitudes that they express. Indeed, the cognitivist has no other proof of the fine-grainedness of moral properties than the fine-grainedness of the predicates that, he claims, pick out those properties.

Indeed, there is some evidence that Shafer-Landau is, in the passage above, placing an explanatory burden upon the expressivist that no cognitivist would be capable of carrying. He writes that expresivists must explain the diversity of moral predicates "by citing a different attitude that receives expression in each case." I don't know of a cognitivist who can cite a different property picked out by each of the myriad of moral predicates -- other than, in most cases, by using those very same predicates themselves. If this is the case, however, it would seem a very strange criticism of the expressivist that she cannot cite an attitude for each predicate, other than by citing the predicate itself that expresses the attitude in question.