Squaring recent research suggesting we're "naturally moral" with all the strife in the world.
In 1999, Joshua Greene—then a philosophy graduate student at Princeton, now a psychology professor at Harvard—had a very fertile idea. He took a pretty well-known philosophical thought experiment and infused it with technology in a way that turned it into a very well-known philosophical thought experiment—easily the best-known, most-pondered such mental exercise of our time. In the process, he raised doubts, in inescapably vivid form, about the rationality of human moral judgment.
The thought experiment—called the trolley problem—has over the past few years gotten enough attention to be approaching “needs no introduction” status. But it’s not quite there, so: An out-of-control trolley is headed for five people who will surely die unless you pull a lever that diverts it onto a track where it will instead kill one person. Would you—should you—pull the lever?