And Lot’s wife, of course, was told not to look back where all those people and their homes had been. But she did look back, and I love her for that, because it was so human.
Slaughterhouse-Five, Kurt Vonnegut
Evolution has taught us to read and understand facial expression beyond language or other forms of expression. From a distance you can usually detect friend or foe. The stranger may be carrying a weapon, but their eyes reveal all.