Remember those who-to-throw-off-the-lifeboat exercises from Ethics class? Well, there’s an app for that — or there needs to be one soon, says Nick Carr:

So you’re happily tweeting away as your Google self-driving car crosses a bridge, its speed precisely synced to the 50 m.p.h. limit. A group of frisky schoolchildren is also heading across the bridge, on the pedestrian walkway. Suddenly, there’s a tussle, and three of the kids are pushed into the road, right in your vehicle’s path. Your self-driving car has a fraction of a second to make a choice: Either it swerves off the bridge, possibly killing you, or it runs over the children. What does the Google algorithm tell it to do?

Answer: it does what the software engineers tell it to do. But what’s that going to be? As Nick concludes, “We don’t even really know what a conscience is, but somebody’s going to have to program one nonetheless.”