At the New Republic, Thomas Nagel has a review of Joshua Greene’s Moral Tribes, and I recommend it to any of my readers who haven’t already read it. Nagel’s main point is given by his title “You can’t learn about morality from brain scans“, and I certainly agree with that. Like most people who think psychology and neuroscience can be used to uncover the basis of sound ethics, Greene is a utilitarian. To make his case, he must explain why, since both utilitarian and non-utilitarian moral intuitions are evolved features of the brain, one is to be regarded as more legitimate than the other. Greene is better than many moral psychologists in that he at least realizes that this is a problem. One argument he makes is that utilitarian intuitions are more universal and more likely to lead to inter-cultural agreement. The funny thing at least in the book review, though, is that the main non-utilitarian intuition discussed (that it is wrong to directly kill in order to save more lives–more on this below) also sounds like it is very widely shared. What’s more, there are utilitarian conclusions (e.g. that one shouldn’t favor one’s own family) that are rejected by almost everyone. Utilitarians themselves generally don’t think we should try too rigorously to be impartial happiness maximizers because it would make us miserable, yet realizing that their philosophy is self-refuting doesn’t seem to discourage them. Greene himself proposes a revealing thought experiment.
He asks what you would do if you had the choice of creating a world full of people like us, or a world full of people whose natural motives were completely unselfish and impartial and who cared about everyone, not just their friends and families, as much as they cared about themselves. He assumes that you would choose to create the second species, and that this shows that there is something the matter with us and our species-typical moral responses.
The funny thing is that my immediate impulse is to choose a world full of people like us. A world of perfect happiness-maximizers would be a world without love (which is essentially partial) and without spiritual greatness (which seeks higher values than happiness). Nagel thinks this thought experiment is perverse, but I disagree. It does show clearly how deep our disagreement with the utilitarians goes.
The book and the review spend a lot of time talking about the trolley problem, and I’d like to take this opportunity to say a word about that. There is an annoying assumption in some discussions of this experiment–especially when it’s the psychologists talking rather than the philosophers–that consequentialism is obviously right and rational, so that the responses of average people to the trolley dilemmas are mere irrational emotion and therefore incorrect. In fact, I think that the average people basically get it right. To a non-consequentialist (who can be as cool-headed and rational as one likes), there certainly are morally relevant differences between the “switch” and “footbridge” scenarios. Consider this. If, after choosing to save the most lives in the switch scenario, you learned that the trolley had missed the man on the other line and hit no one, you would be elated; the choice would have turned out to be even more successful than you had hoped. If, after choosing to throw the fat man in front of the trolley, you find out that the trolley had missed him, you would regard your move as a failure. In the second but not the first case killing someone is necessarily connected to the desired outcome. You want to save lives by means of killing someone. The person dying is not just a foreseeable outcome of the choice; it is part of the chain of causality that gets you to your goal. This is important for whether the principle of double effect can be invoked. I also say that, if the prohibition against murder is to be preserved at all, we must retain the distinction between direct killing and any random action that fails to minimize the number of people dying at a given time. That is, in evaluating an act, we must be able to identify the object as well as the intention and the consequences. There is room for discussion in how we draw the line of what is direct killing, but it is not a priori unreasonable that it turn out that switch falls on one side and footbridge on the other.