ETHOS
Ethos (Greek for 'character') is an ethical appeal, and uses the good moral character of the author to convince the reader. Ethos is often conveyed through tone and style of the message and through the way the writer refers to differing views. Ethos can also be affected by the writer's reputation as her reputation exists independently from the message--his or her expertise in the field, his or her previous record or integrity, and so forth. We tend to believe people whom we respect. One of the central problems of persuasion is to make yourself as an author into an authority on the subject of the paper, as well as someone who is likable and worthy of respect.