That's because checklists adapt better to change than commandments. Sailors rely on them before going to sea. Soldiers employ them in planning missions. Surgeons demand them, to make sure they'll have the instruments they need and that they'll leave none behind. Pilots run through them, to ensure taking off safely and landing smoothly--preferably at the intended airport. Parents deploy them against all that can go wrong in transporting small children. Checklists pose common questions in situations that may surprise: the idea is to approach these having, as much as possible, reduced the likelihood that they will.