If your goal is to obligate your audience to believe the truth (as it should be), don’t let your audience waste your time and energy “defeating” a logical argument that, in reality, they don’t care about (or at least, is only of derivative importance to their position). What’s the crux? Ethos: proof by means of character (yours or an authority’s). Pathos: proof by means of emotion. Logos: proof by means of reason and argument. It’s irrelevant.