The Moral Brain

Imagine this: you are paddling a
canoe along a jungle river when you spot a group of crocodiles gliding swiftly
through the water with deadly intent. Happily for you,  they are not heading in your
direction – their sights are set firmly on a family of swimmers at the
water’s edge. If nothing is done the crocs will soon have all five of
them for dinner.

By driving your canoe into the
crocodiles you could send them off in a different direction, but this would put
the hungry reptiles directly on course to a sixth swimmer.

So what should you do? Allow
things to take their course, and allow five to die? Or intervene and reduce the
toll to one?

Thought experiment enthusiasts
might recognise this scenario as an exotic version of the famous “runaway
train” dilemma, in which five pedestrians are about to be mown down
unless you, the bystander,  throw a switch which will divert
the train to a track where just one reckless track-walker will be killed.

Over the last three years some
quarter of a million people have responded to the train dilemma via a web-based
survey posted by evolutionary psychologist Marc Hauser and his colleagues  at
the Harvard Cognitive Evolution Laboratory. The  vast majority of respondents
– some 90%-  say they
would  flip the switch .

The Harvard reserachers
invented the crocodile-canoe variation to help establish whether this moral
judgement is learned or “hard-wired” into our brains. They used it
on the Canu Indians, a tribe whose world is so
different from that of the Internet sample that they wouldn’t know a
train if one…er…..hit them. Despite the
vast cultural difference between the two groups, however, they both judged the
situation in almost exactly the same way, supporting the idea that moral
decision-making
is more instinctive
than conditioned.

Instinctive judgements, by
definition, are not arrived at rationally, so this may explain why many of our
moral presumptions are nonsense.

Most people, for example, think it
is worse to attain a given end by actively harming someone, than to achieve the
same end by omitting to prevent the harm occurring. Another thought experiment
illustrates the point:

Scenario one is this:
Six-month-old Jimmy is all that stands between his Wicked Uncle Sidney and a
large inheritance. So Sid has volunteered to baby-sit
his nephew with the intention of doing him in. Come bath time he plans to hold
the baby under the water, then claim that the drowning
happened when he momentarily left the room.  Jimmy’s Mum places the baby in the
bath before she leaves the house, then hands over to Sidney  who enters the bathroom and duly
murders the child.

In scenario two Sid enters the
bathroom full of evil intent but then  sees that little Jimmy has  tipped himself upside down and is  about to drown anyway. Sidney could scoop him out and save his life
or he could do nothing.  He decides
to do nothing.

When people are asked  to measure out blame in each
case, they invariably rate Sid’s active drowning  of Jimmy as more morally reprehensible
than his omission to save him. Yet in both cases  Sidney’s  intention – to bring about the
death of Jimmy – is identical, and so are  the consequences. These are the  factors that
people consciously think matter, yet their judgement does not reflect this.

Using thought experiments like
these, Hauser has determined that our moral judgements are based on three
largely “hidden”  principles:

One  - as shown by the
Sidney/Jimmy scenario – is that
harm caused by positive action is morally worse than equivalent harm
caused by omission.

The second is that doing harm in
order to achieve a
goal is worse than knowingly allowing harm to be done in
pursuit of the goal.

To illustrate this  Hauser uses  another version of the runaway train
theme. The train is again  on course to run over five
people, but you can divert it. Instead of sending it off in another direction,
though, this diversion takes the train on to a loop which rejoins the main
track before it reaches the hitchhikers. There would be no point in sending it
this way, except that there  happens
to be a very fat man walking along the tracks on the loop so if you do the
train would hit the fat man and his weight would bring it to a halt. Five
people would thus be saved, and one killed.

This is very similar to the
“basic” runaway train experiment, but whereas in that the one who
was killed was a “side effect” of preventing the others’
death, in this case he is the means by which the train is stopped.

It seems like a subtle difference
– so subtle, in fact, that most of us don’t see it unless it is  spelt out.
Yet unconsciously
it makes a lot of difference: whereas 90%  think its ok to allow the man to
be killed, only about half  of us
agree that it is ok to kill him in order to save others.

The third principle is that doing
harm by using physical contact is worse than harm done at arm’s length.. If people are asked if it is ok to use the fat man to
stop the train by actually  pushing
him into its path, the number who say yes drops right down to 11%, even though
– for the fat man the distinction is really quite academic. .

Thought experiments may seem like
a game but these ones have serious implications because the way that we judge
right or wrong determines our whole system of crime and punishment, Speeding a
person’s demise, for example, is legal if it involves not doing
something that would prolong life, but (in most places) illegal if involves
actively doing
something to bring about death. Killing civilians in a war is a
criminal act, but
when the deaths are called “collateral damage” they
are treated as  merely regrettable.
By exposing these intuitive,  nonsensical, judgements runaway
trains, hungry crocodiles and wicked Uncles may yet help to make our world a
fairer place.

Marc Hauser's website

You can take the Harvard Moral
Sense Test for yourself here.