Supporting arguments for any thesis statement have roots in one or more of three essential forms of persuasion: logos, pathos, and ethos.
1) Logos arguments appeal to the reader’s sense of logic. For example, writers may present readers with a syllogism such as a simple if/then proposition.
2) Pathos arguments appeal to one or more of the reader’s emotions. For example, writers may augment their other arguments with narrative anecdotes that help readers feel the human element or impact of their position. A writer may also choose specific language or examples that help undermine and/or demonize their opposition.
3) Ethos arguments appeals to the readers sense of credibility or authority. For example, writers might cite historic precedent, their own years of first-hand and/or professional experience with a particular topic, or the views of an expert in the applicable field. Writer’s should not confuse an ethos argument with an ethical argument. As a form of authority, ethical arguments represent just one type of ethos argument, and they often have little influence on the reader—because, for an ethical type of ethos argument to work, the topic of debate must relate to some element of morality, and the reader and the writer must adhere to the same notions of morality.
Many excellent arguments will incorporate more than one form of persuasion. For example, an ethos argument referencing the authority of historic records may also provoke a powerful emotional response.
Thoughts, Revised & Refined 