Train coming

Say there's a group of five people standing on a train track, with a train coming toward them. You can save the whole group by pulling a lever and switching to another track, but the catch is that you'll kill another person who's standing on that other track. Do you pull the lever?

According to Harvard scientist Mark Hauser, who posed this question to hundreds of thousands of people on the Internet, nine out of 10 people say yes, they would pull the lever. But the next question was a bit harder—and the answers much more confusing.

In the second scenario you're on a trestle standing above the tracks and again there is a group of five people standing down track who are about to die. There is also a large man standing in-front of you. If you push him, he'll fall onto the track, stop the train and save the group of five. Would you push the man?

This time Mark Hauser, again posed the question to hundreds of thousands of people, nine out of 10 people said they would NOT push the man. It's an interesting moral quandry; in both instances you're actions lead to the death of someone, but the act of arriving there is processed by our brains differently. He ran tests posing questions like this while using an MRI to imaging the brains of respondents. He discovered that we process moral decisions and will arrive at different conclusions because of how our minds have evolved. Even more interesting, Mark's theory is that morality is hardwired into our genetics.

Listen to the full Episode on "This American Life" here: Who Can You Save?