Edward is the driver of a trolley, whose brakes have just failed. On the track ahead of him are five people; the banks are so steep that they will not be able to get off the track in time. The track has a spur leading off to the right, and Edward can turn the trolley onto it. Unfortunately, there is one person on the right-hand track. Edward can turn the trolley, killing the one; or he can refrain from turning the trolley, killing the five.
Which way was the trolley intended to go?
He could turn it onto the track with just the one, but what if that one knew that the train wasn't supposed to drive there, and so it was safe for him to do a bit of work on the track?
I vote go for the route that was intended in the first place. If that kills five people rather than just one, it's unfortunate.
But if you turn to avoid someone who had not taken precautions and shown regard for their own safety at the expense of someone who has done this, it kind of goes against evolution...
Regardless of which way is chosen someone dies. But who is to blame? The driver was powerless to stop it, and his choice was between two evils, so to speak. Maybe the responsibility lay with the one who was supposed to keep the breaks in working order?
But if there were two tracks and time to change which one to go for, maybe there would be time for Edward to open the window and shout for the one guy to run over to the five and clear one of the tracks?
(These problems about "kill one or kill five" are difficult. How do we measure the worth of human lives? In numbers? "Kill the one, because that is less than five dead". That kind of thinking is centered around the greater good, and it certainly doesn't benefit the one. In that context five dead isn't much worse than one. What if the five were a gang of thieves, murderers and rapists, and the one was a hard working contributor to the community? How to decide? Save the one with the nicest shoes?)