Humans will soon subcontract their ethical dilemmas to machines. We must be prepared to make some tough choices
Loved by some philosophers, loathed by others, the so-called trolley problem is the quintessential moral puzzle. A runaway train is heading towards five people tied to a track. You can change a signal, diverting the train down a spur, so saving five lives. Unfortunately, one person is on the spur, and would die. What should you do? Most people – young and old, rich and poor – believe you should divert the train.
But what if a runaway train is heading towards five people, again tied to the track, and you are standing on a footbridge overlooking it, next to an overweight man? Once again you can save five lives, but only by toppling the heavy-set man over the bridge: he will die, but he is large enough to slow the train to a stop. What should you do? This time, almost everyone agrees that you should not kill one person to save the five lives.