You are walking on a bridge above a railway track and notice, to your horror, that five people are tied to the rails in the path of the oncoming rail trolley. You see that in front of you is a man teetering on the edge of the bridge, a man so large and fat that his sheer bulk would stop the trolley in its tracks and save the five people currently in the path. This man is the man who tied the people to the tracks.
Do you push the fat man off the bridge ?
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We had that question in a management training session a couple of years ago and it provoked a lively moral debate!