Magazine article The Times Higher Education Supplement : THE

A Test Track for Moral Reasoning

Magazine article The Times Higher Education Supplement : THE

A Test Track for Moral Reasoning

Article excerpt

Jane O'Grady on a thought experiment that is an endless platform for exploring ethical principles

The Trolley Problem Mysteries

By F. M. Kamm Edited by Eric Rakowski, with commentaries by Judith Jarvis Thomson, Thomas Hurka and Shelly Kagan

Oxford University Press, 272pp, £19.99

ISBN 9780190247157 Published 21 January 2016

The brakes of a tram fail suddenly. Ahead are five people working on the tracks. The tram will ineluctably kill them unless the driver steers the brakeless tram on to a branch line, where the lone person on the tracks would be killed instead. What should the driver do? Offered this imaginary predicament, most of us opt for diversion to the branch line. Why then, asks philosopher Philippa Foot, who devised this thought experiment in 1967, do we see so differently the case of a surgeon killing someone so as to distribute that person's organs between five people who would otherwise die? The outcome in both cases is the same - five lives are saved at the cost of one - yet somehow we baulk at the thought of the high-handed surgeon.

Since 1967, Foot's tram has changed into a trolleybus (America), then into a train. It has careered off into numerous varying scenarios, acquiring all sorts of extra protagonists along the way, as well as bombs, tractors, looped lines, lazy Susan swivel-levers and other paraphernalia. Judith Jarvis Thomson added the new dimension of what a bystander to the scene would be justified in doing to pre-empt the trolley's inexorable progress towards the five workers: push a fat man off a bridge on to the trolley tracks, for instance. In the almost half a century since Foot's famous paper, her thought experiment has been elevated into a specialised area of ethics, jokingly called "trolleyology".

The Trolley Problem Mysteries consists of the 2013 Tanner Lectures on Human Values - given at the University of California, Berkeley by Frances Kamm, a trolley aficionado - and some of the responses to them. Thought experiments, as Kamm reminds us, are "constructed, like scientific experiments, to distinguish among and test theories and principles". How right it sounds, both morally and rationally, to say that an action is good to the extent that it produces the greatest happiness (and least suffering) in the greatest number. But applying this general (utilitarian) principle to particular, if hypothetical, situations can highlight dubious factors in it that grate against our intuitions, inducing us to question, revise, even discard, consequentialist theories. Is an action's outcome the exclusive determinant of that action's rightness or wrongness?

Kamm is a self-styled non-consequentialist, but she has always agreed with consequentialists that what crucially distinguishes the Fat Man Case from the Driver's Two Options is not the distinction between killing and letting die, because these are often tantamount to the same thing. Nor, she says, would Thomson's distinction between redirecting an already-existent threat and creating a new one be of any help: surely driver or bystander could sometimes be justified in creating a threat subsequent to the original brake failure, for instance if swivelling a turntable would save the five people on top of it only because it deliberately causes a rockslide to push a passerby on to the tracks. With characteristic ingenuity, Kamm argues that what explains why our intuitions are affronted in some cases but amenable in "structurally similar" ones is "how we bring about the harm that will have a necessary causal role in saving the five". According to her "principle of permissible harm", when the driver saves the five by deflecting the trolley towards the one, "the five being saved is simply the trolley's moving away"; the one being killed is that movement's "noncausal flip-side". With the Driver's Two Options, one person is "substituted" for the five, which is permissible; but in the Fat Man Case, he is "subordinated" to them, which is not. …

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