A study by the anthropologist Keith Basso of Apache subjects lists the circumstances wherein participants routinely adopt silent behavior. They include meeting strangers, early stages of courtship, being with “someone for whom you sing,” sitting with the bereaved, and greeting children just returned from Bureau of Indian Affairs boarding schools. Insults too are met with silence. In sum, Apaches turn silent when the situation is ambiguous, unpredictable, potentially dangerous even.

George Michelsen Foy, Zero Decibels, loc. 387