A MORAL DILEMMA

 Consider the following case: A brain in a vat is at the wheel of a runaway
 trolley, approaching a fork in the track.  The brain is hooked up to the
 trolley in such a way that the brain can determine which course the trolley
 will take.  There are only two options: the right side of the fork or the left
 side.  There is no way to derail or stop the trolley, and the brain is aware
 of this.  On the right side of the track there is a single railroad worker,
 Jones, who will definitely be killed if the brain steers the trolley to the
 right.  If Jones lives he will go on to kill five men for the sake of thirty
 orphans (one of the five men he will kill is planning to destroy a bridge that
 the orphans' bus will be crossing later that night).  One of the orphans who
 will be killed would have grown up to become a tyrant who made good
 utilitarian men do bad things, another would have become John Sununu, and a
 third would have invented the pop-top can.

 If the brain in the vat chooses the left side of the track, the trolley will
 definitely hit and kill another railman, Leftie, and will hit and destroy ten
 beating hearts on the track that would have been transplanted into ten
 patients at the local hospital who will die without the donor hearts.  These
 are the only hearts available, and the brain is aware of this.  If the railman
 on the left side lives, he, too, will kill five men -- in fact, the same five
 that the railman on the right would kill.  However, Leftie will kill the five
 as an unintended consequence of saving ten men: he will inadvertently kill the
 five men as he rushes the ten hearts to the local hospital for
 transplantation.  A further result of Leftie's act is that the busload of
 orphans will be spared.  Among the five men killed by Leftie is the man
 responsible for putting the brain at the controls of the trolley.  If the ten
 hearts and Leftie are killed by the trolley, the ten prospective
 heart-transplant patients will die and their kidneys will be used to save the
 lives of twenty kidney-transplant patients, one of whom will grow up to cure
 cancer and one of whom will grow up to be Hitler.  There are other kidneys and
 dialysis machines available, but the brain does not know this.

 Assume that the brain's choice, whatever it turns out to be, will serve as an
 example to other brains in vats, and thus the effects of its decision will be
 amplified.  Also assume that if the brain chooses the right side of the fork,
 an unjust war free of war crimes will ensue, whereas if the brain chooses the
 left fork, a just war fraught with war crimes will result.  Furthermore, there
 is an intermittently active Cartesian demon deceiving the brain in such a way
 that the brain is never sure if it is being deceived.

 Question: Ethically speaking, what should the brain do.  Justify your answer.

 [Taken from Harper's Magazine, May 1996; originally appeared in in bOING
 bOING, a quarterly published in Los Angeles]