Among the many theories of the study of speech, one widely recognized as important is the "good man theory." The main point is that a speaker must have a good, conscientious mind, and only then can one say things of benefit to society.
「口頭傳播學」的眾多理論之中，學者們公認「善人說」（good man theory）最為重要，主要原因是，說話的人必須心地善良，才會說出有益社會人心的話來。