The so-called trolley problem teaches cadets moral instincts to use in combat
By David Edmonds
BBC, West Point
US Army cadets have to face the moral conundrum of taking one life in order to save the lives of others. David Edmonds considers this dilemma with trainee soldiers studying philosophy at the West Point military academy in New York state.
"Leave hotel and call press man, Jim."
"0820, park car; to be met by Jim."
It is the beginning of our schedule which is set in stone, or at least in paper, with military precision.
This is no surprise because we are at West Point, where future officers of the US Army come to train.
Timekeeping is a given, not a virtue.
The new breed of philosopher soldiers are being taught Immanuel Kant, who thought that there were some things it was always wrong to do to other humans whatever the consequences
"0840-0925, attend class."
"0925-0950 movement from class to Lincoln Hall."
It is all very impressive and a little intimidating.
At 0800 I call Jim, as laid down in the schedule.
"Sorry," Jim says, "I'm running late."
He has a good excuse. It is sleeting heavily.
West Point sits on the Hudson River, which with clear skies looks vast and beautiful as it meanders its way through the wilderness towards New York City.
But when it is sleeting, it is barely visible.
I am here for a strange reason - to see whether cadets would kill a fat man.
There is a famous conundrum in moral philosophy.
Imagine there is a runaway tram, known in America as a trolley, heading towards five people tied to the track.
You are a bystander.
If you do nothing, all five will die.
THE TROLLEY PROBLEM
Invented by moral philosopher Professor Judith Jarvis Thomson, who taught at Massachusetts Institute of Technology
Case one: A runaway tram is heading towards five people tied to tracks. You are a bystander. Would you flick a switch so it turned down a line where one person was tied to the tracks?
Case two: Same problem, but you are watching from a footbridge. You could push a fat man next to you off the bridge, and his bulk would stop the tram. Would you do it?
But you could hit a switch and divert it down a side track.
Unfortunately, on that spur is one person and if you turn this tram, this person will die.
What should you do? Turn the tram? Most people think you should.
Now imagine that same tram is again heading towards five people. This time you are watching from a footbridge.
There is a fat man leaning over this footbridge. If you push him over, he will land on the track and die, but his bulk will stop the tram.
So should you push the fat man? Almost no-one thinks you should.
Why might it be acceptable to turn the tram and kill the man on the track but not acceptable to push the fat man?
The solution to the conundrum has implications in numerous practical areas, including warfare.
All West Point cadets now study philosophy and the so-called trolley problem, a problem that continues to absorb some of the most brilliant minds in moral philosophy.
These include Jeff McMahan, of Rutgers University, who has also taught at West Point.
You can see the kind of rigour and attention to detail required for philosophy as you watch Professor McMahan make tea.
People have a duty to do the right thing, even if it produces a bad result
People should always be treated as valuable - as an end in themselves - and should not just be used in order to achieve something else
It is wrong to tell a lie in order to save a friend from a murderer
"The tea has to be brewed at exactly 180F (82C)," he says.
It is important that a McMahan cup of (green) tea, is steeped for precisely six minutes - a timer is set, in case the philosopher becomes preoccupied with other things.
Once the tea is ready for consumption, McMahan forcefully makes the claim for the relevance of the trolley problem.
He says it adds weight to a crucial moral distinction - enshrined in international law - between killing civilians as an aim, and knowing civilians will die merely as a foreseen consequence of military action: between attacking a munitions factory aware that there will be, to use that euphemism, collateral damage, and aiming at civilians intentionally.
In the classroom the new breed of philosopher soldiers are being taught Immanuel Kant, who thought that there were some things it was always wrong to do to other humans whatever the consequences, and without whom the modern conception of human rights is almost inconceivable.
The lecturer, Chris Case, explains Kant's insights about lying and hypocrisy, using the example of a preacher in the 1980s.
This being a military school, the language has several pots more salt than you would hear at a more traditional educational establishment.
"Remember, that hell-fire and brimstone guy," says Chris Case.
"Well, when nobody was looking he was in the bathtub with a hooker peeing on his head."
The cadets snigger.
Major Danny Crozier admits that there is a danger in teaching cadets to think reflectively for themselves - the danger of insubordination
"Now people got pretty mad at that, and not because they thought there was anything necessarily wrong with having a hooker pee on your head. It was because that SOB told me that I ought not fool around with people I'm not married to - and he was doing it himself."
It is hard to know how the 18th-Century German philosopher would respond to this updating of his philosophy.
Outside the classroom, one officer, Major Danny Crozier, admits that there is a danger in teaching cadets to think reflectively for themselves - the danger of insubordination.
But the risk is worth it, he says, because soldiers must not obey unjust commands.
Philosophy can help them draw the necessary distinctions.
His young soldiers could be required to go to Afghanistan before the US military pulls out in 2011, and if engaged in combat will have to take snap decisions about what to target, when to shoot.
Their moral instincts have to be trained alongside their military ones.
I watch Major Crozier smile with quiet satisfaction as we put the well-known philosophical conundrum to the young cadets.
One by one they tell us why, in their carefully considered judgement, it would be quite wrong to push the fat man.
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