Among the maxims of basic training for scuba divers is “Never dive alone”. Wise divers go with a “buddy” to both share the fun and to be able to help each other in case of emergencies like equipment failure. Every diver typically carries a primary and a spare regulator (mouth-piece that delivers the oxygen from the tank), but in a pinch, divers can share a regulator off the same tank while making an emergency ascent to the surface. It’s up to each buddy to watch the other and to intervene if needed. If wide eyes and flailing arms aren’t enough notice, the sound of a dive knife beating on a metal tank will quickly bring a good buddy near with life-saving air and support.

Unlike well-trained divers, we are not so good at letting others see our need for help....