The Trolley Problem, Tested

The Trolley Problem is a classic thought experiment in ethics that goes something like this:

There is a runaway trolley barreling down the railway tracks. Ahead, on the tracks, there are five people tied up and unable to move. The trolley is headed straight for them. You are standing some distance off in the train yard, next to a lever. If you pull this lever, the trolley will switch to a different set of tracks. However, you notice that there is one person tied up on the side track. You have two options:

  1. Do nothing, and the trolley kills the five people on the main track.
  2. Pull the lever, diverting the trolley onto the side track where it will kill one person.

Which is the most ethical choice?

When surveyed, the vast majority of respondents say they would choose to kill the one and save the five.

But would they really?

The Trolley Problem is difficult to test, due to ethical concerns of causing emotional and psychological harm to participants.

But on the first episode of the second season of YouTube Red series Mind Field, Michael Stevens of Vsauce conducts what may be the first real-world Trolley Problem simulation.

Participants are led to believe they’re at the helm of a railroad switch. An operator (actor) teaches them how to use the switch before excusing himself to take a phone call. “Live” video feeds above the control panel show a train approaching five construction workers on one track, and the participants have the opportunity to switch the train over to a second track where only one worker is standing.

To the participants, it feels like a real life-or-death situation, and it’s up to them to decide who lives and who dies.

To keep the study ethical, all participants were screened in advance for a history of post-traumatic stress and other traits that could make them susceptible to lasting harm. They were also debriefed immediately after the simulation, and on-site counseling was provided.

Despite the small sample size in this study, there was a clear pattern: most people froze, unable to make a decision with such serious consequences.

However, a couple of people did flip the switch. It was fascinating to see their presence of mind in that moment and hear their thoughts after the fact.

Note: you will need a YouTube Red subscription to watch this video. If you can afford the $9.99 a month, I feel it’s well worth it—even if only to watch Mind Field.