One has to be able to give the other person mental elbow room. During our winter, when a person settled into the sofa in the salon with a book and started reading, he or she was not interrupted."How to get along for 500 days alone together"
Keeping quiet when the person is close enough to practically read one's thoughts, is a matter of self-discipline, fuelled by caring.
The only exception to our silence rule was for boat-related safety issues. The boat, for obvious reasons of survival, always came first.