The future may or may not look like the "Terminator" movies, but our machines are certainly making inroads.
We've had drones stop responding to commands, and had stock-trading computers trigger sudden drops in the markets.
And even non-electronic technologies can act up, as ethicist Wendell Wallach points out in his book A Dangerous Master: How to Keep Technology from Slipping Beyond Our Control.Wendell joined us in 2015, and we return to the interview here.