It is a hypothetical problem that assumes that the people out there on the rails are either completely blind or irresponsible. The problem also takes a purely western perspective of morality, but bases presumed intent based on the action, which is logically incorrect. In the Indian model, what matters is the intent. Thus, for example sacrificing a fat man to stop the train is certainly ill-intentioned since a man who had done nothing is being punished to save those who were perhaps unconscious and inattentive about the train.
Generally, the instinctive action of a truly moral man would be to wave or scream or show a red flag to stop the driver while simultaneously diverting the train to the track where there is one person. It is also easier to scream or even throw something at the single person to draw his attention to the train while diverting the train to the other track.
However, the real catch here is that it is no fault of the single person since he is well within his mind to assume that there is no train scheduled to pass by on the given track; hence, he is likely to be inattentive by default. On the other hand, the five persons on the track should have known or been attentive. They have acted truly unconsciously and hence are clearly at fault. Nature’s justice would be to let them be hit, as they ought to have known that a train is expected.
However, the problem changes completely if there are five little children playing on the scheduled track and one adult on the other track. In such a case, the train should be diverted since an adult still has a chance to save himself while children might not be.
Normally however, diverting is not a good option if there is one person who is standing there. It is no fault of his since the train is not expected there. Normally and rightly, he should do everything within his means to alert the five persons but let the train go through the scheduled route, hoping and praying for an intervention such as the driver suddenly realising and stopping the train just in time.
Like all mental problems, there are many important missing elements, such as the state of the five persons (who might be drunk) and hence the solution can never be perfect.
Affectionately,
Alok Da
