The classical concept of "ethos" (the establishing of the speaker or writer's credibility, his or her moral character) has acquired many meanings over the centuries and has played an important role in determining the many shifting perceptions of the teacher's role, both in the classical period and the modern period. The issue can be reduced to this one classical concept, and the dialectic pair that overshadows it--philosopher and moderator. A moderator may be seen as a teacher who monitors students' acquisition of persuasive skills, without concern for the moral implications of the students' use of the material or techniques they are being taught. A philosopher teaches rhetorical skills, but also supplies students with a moral model, and teaches the truth. The original dichotomy between the role of the teacher as philosopher or moderator began with the schism that developed between the followers of Socrates, perhaps the original philosophical educator, and Gorgias, who is often portrayed as the penultimate sophist. The views of Plato, Gorgias, Isocrates, Aristotle, Cicero, and Quintilian illustrate a range of opinions regarding this issue. The voices of current theorists convey equally strong opinions concerning the writing teacher's role. All teachers have their own ethos and only they can determine what ethical stance is best for them. But it is a position that must be questioned rather than blindly acquired. (SR)